ROHM BD6592MUV handbook
Contents
1. VBAT VREG VBAT VIN detector pa PWMPOW AN A A VDET PIN PIN PIN FAILSEL SND GND over voltage protect 1 d f A B c CA gt 1 VBAT VBAT sw i sence gt i LED2 e i ISIN LED3 VAN SENSP N iph LED4 PIN PIN I PIN SENSN Saree LEBS ZN 5 5V j iD LED6 J gt f ND no Clump i LED TERMINAL D E F Detect f 1 VBAT VREG Test a X PWMDRV PIN ZN ISETH cH 5 ISTH oto SND sen pH AN eR GND GND GND GND Fig 23 Block diagram Fig 24 I O equivalent circuit diagram Q Pin assignment table PIN In Out PIN Function Terminal equivalent Name number circuit diagram 1 VDET In Detect input for SBD open and OVP C 2 N C No connect pin F 3 GND GND B 4 SW Out Switching Tr drive terminal G 5 SENSP In Side Current sense terminal G 6 TEST In TEST input Pull down 100kQ to GND G 7 SENSN In Side Current sense terminal A 8 GND GND B 9 ISETH In Resistor connection for LED current setting at PWMDRV H A 10 ISETL In R2. Coil Value Manufacturer Product number Vertical ee Height max iar a pu 4 7uH TOKO A915AY 4R7M 5 2 5 2 3 0 1870 0 045 4 7uH TOKO B1015AS 4R7M 8 4 8 3 4 0 3300 0 038 4 7uH TOKO A1101AS 4R7M 4 1 4 1 1 2 1400 0 115 4 7uH TDK LTF5022T AR7N2RO 5 0 5 2 2 2 2000 0 073 4 7uH TDK VLP6810T 4R7M1R6 6 3 6 8 1 0 1600 0 167 10uH TDK VLP6810T 100M1R1 6 3 6 8 1 0 1100 0 350 Capacitor Value Pressure Manufacturer Product number Vertical EE Height TC LM Supply voltage capacitor 10uF 25V MURATA GRM31CB31E106K 3 2 1 6 1 6 0 2 B 10 10uF 10V MURATA GRM219BB31A106K 2 0 1 25 0 85 0 15 B 10 4 7uF 25V MURATA GRM319B31E475K 3 2 1 6 0 85 0 1 B 10 4 7uF 25V MURATA GRM21BB31E475K 2 0 1 25 1 25 0 1 B 10 Smoothing capacitor for built in regulator 1yF 10V MURATA GRM188B10J105K 1 6 0 8 0 8 0 1 B 10 2 2uF 10V MURATA GRM219B11A225K 2 0 1 25 0 85 0 1 B 10 Output capacitor 1yF 50V MURATA GRM31MB31H105K 3 2 1 6 1 15 0 1 B 10 1uF 50V MURATA GRM21BB31H105K 2 0 1 25 1 25 0 1 B 10 1yF 100V MURATA GRM31CR72A105K 3 2 1 6 1 6 0 2 X7R 10 2 2uF 50V MURATA GRM31CB31H225K 3 2 1 6 1 6 0 2 B 10 0 33uF 50V MURATA GRM219B31H334K 2 0 1 25 0 85 0 1 B 10 Resistor Value Tolerance Manufacturer Product number EE Vertical Horizontal Height Resistor for LED current decision ISETH pin 16kO 0 5 ROHM MCROO6YZPD
3. RTRO20N05 FAILSEL VDE FAILSEL VDE SENSN Power f ON OFF RSTB f PWMPOW 100Hz 10kHz PWMDRV PWM Power sey RSTB PWMPOW EEDI 100Hz 10kHz PWMDRV PWM VBAT VBAT VREG VREG Each 40mA Each 40mA Can be set up to each15 40mA Can be set up to each15 40mA Fig 50 8 seriesx3 parallel LED current 40mA setting Fig 51 6 seriesx4 parallel LED current 40mA setting Current driver PWM application Current driver PWM application www rohm com 19 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note OG Application example LED current setting controlled ISETH resistor 24kQ 20mA 16kQ 30mA 12kQ 40mA Brightness control Please input PWM pulse from PWMPOW or PWMDRYV terminal Please refer electrical characteristic p 3 and function p 13 inch panel Battery Battery pi 10uF 3 4 7yH 4LED x 6parallel PE 10yF 3 4 7uH 8LED x 3parallel DF Dr 2 2yF 2 2yF d p RTRO20NO5 sw FAILSEL og RTRO20NO5 Sw FALLSEL ue SENSP SENSP 68mQ I 68mQ i n SENSN 4 SENSN ON OFF RSTB ON OFF
4. 44mA Je act LED 0 6V 10mA d PWMDRV LED 0 7V OmA 4 LED3 VBAT ISET voltage m eS LEDS LED current 2204 GND GND GND GND TEST ISETH ISETL LED6 470kQ Each 20mA 0 6V typ LED current 470kQ Fig 62 Analog style optical application www rohm com 2011 ROHM Co Ltd All rights reserved 23 25 0 6V D A 24kQ bon 2011 06 Rev C BD6592MUV Technical Note Notes for use 1 Absolute Maximum Ratings An excess in the absolute maximum ratings such as supply voltage temperature range of operating conditions etc can break down devices thus making impossible to identify breaking mode such as a short circuit or an open circuit If any special mode exceeding the absolute maximum ratings is assumed consideration should be given to take physical safety measures including the use of fuses etc 2 Operating conditions These conditions represent a range within which characteristics can be provided approximately as expected The electrical characteristics are guaranteed under the conditions of each parameter 3 Reverse connection of power supply connector The reverse connection of power supply connector can break down ICs Take protective measures against the breakdown due to the reverse connection such as mounting an external diode between the power supply and the IC s power supply terminal 4 Power supply line Design PCB pattern to provide low impedance for the wiring between the power supply and the GND lines In this
5. 200Hz Expansion PWM 200Hz Driver Control PWM PWMDRV f u 1 PWMPOW sj Max Matching Max LED Current Average Current hen Max Matching Max LED Current Average Current E VOUT E t z E E Min Matching Min LED Current Average Current E LED Current ching Min LED Current Average Current 10mA div B i 0 20 40 60 80 100 OL 2 4 8 ah 10 Ce iia i 200m MMa0 a PWM HI Duty PWM HI Duty Fig 18 Fig 16 Fig 1 d VOUT response LED current matching PWMPOW HI Duty LED current matching PWMPOW HI Duty Power Control PWM PWMPOW PWM 200Hz Expansion PWM 200Hz a VBAT 8 L 12V 22V VBAT e N Q T i 14ms VOUT N e LED Current mA 8 N LED current N N LED current R N o N a 3 H 3 i Chi 10 0V amp WIE 5 00V M 100ps Ch 10 0V SIE JV M2 00ms Ch4 10 0mA Cha 10 0mA temp C Fig 19 Fig 20 Fig 21 LED current Temperature Line Transient 10V to 22V Line Transient 22V to 10V PWMDRV H ISETH 30kQ 16mA setting 10 0V WCh2 1 00 A OM 10 0ms Fig 22 VOUT OVP LED OPEN www rohm com 4 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Block diagram I O equivalent circuit diagram VBAT VREG RSTB
6. Fig 25 10 series x 6parallel Fig 26 10 series x 4parallel Hi current 40mA setting Hi current 40mA setting Current driver PWM application Current driver PWM application Please select the capacitor which the little bias fluctuation Battery Battery b 10ygF 4 7yH 1OLED x 6parallel pu 10uF 4 7yH 10LED x 6parallel Dot gt 2 2yF S 2 2yF p p RTRO20N05 I D PAN SEN RTRO20N05 Sw FAILSEL pe SENSP 47mQ i L 47mQ sy SENSN SENSN ON OFF RSTB outer RSTB LED1 PWMPOW Pept LED2 LED2 200Hz PWMDRV LED3 PWM T PWMPOW 200Hz PWMDRV PWM VBAT LED3 LED4 VBAT 2 7V to 5 5V VREG LEDS VREG LEDS 2 2uF GND GNDGND GND TEST ISETH ISETL LED6 GND GND GND GND TEST ISETH ISETL Epg pm Each 30mA Each 40mA Fig 27 10 series x 6parallel LED current 30mA setting Fig 28 Non used Inside REG Power control PWM application or operating under 5V application Please select the capacitor which the little bias fluctuation Terminal processing TEST pin Connect to GND N C Nothing specified in particular Open is recommended VREG When IC is driving from the outside of 2 7 5 5V short VBAT and VREG and put the voltage to VREG FAILSEL PWMDRV Connect to GND in case of fixing at L level Connect to VREG of IC or the power supply of more than 1 4V in case of fixing at H level LED1 6 When each LED driver are not used
7. 2 9 2 1 124uUA 6 45kO 2 2 When use the current driver of 3 parallel 2 9V to RSTB power supply restriction resistance value x 4309A 100 C input current gt 2 1V restriction resistance value lt 2 9 2 1 430UA 1 86kOQ In addition the selection number of parallel number of the current driver is changed the power supply current of RSTB will be increased Because the maximum value of the consumption current at the RSTB 2 1V is indicated in the following Table 1 be careful enough when you calculate the restriction resistance Table1 The use parallel number of current driver at RSTB 2 1V 100 C vs RSTB input current Parallel numbers used for current driver RSTB input current 0 12mA 0 23mA 0 33mA 0 43mA 0 53mA 0 63mA 0 74mA oO L mN o o0 o G How to select the number of LED lines of the current driver When the number of LED lines of the current driver is reduced the un select can be set the matter that the unnecessary LED1 6 terminal is connected to GND When it uses with 4 lines and so on it can correspond to it by connecting 2 unnecessary lines to GND RSTB is used as a power supply of this decision circuit The select of the terminal is judged It has no relation to the logic of PWMPOW and PWMDRYV and it isn t judged an unnecessary LED line even if it is connected to GND when it is judged a necessary terminal once This information can be reset by setting RSTB at OV Q Start control and
8. L value Example 4 7uH output capacitor 2 2uF 50V 1pcs 6 8uH output capacitor 2 2uF 50V 2pcs 10uH output capacitor 2 2UF 50V 3pcs This value is just examples please made sure the final judgment is under an enough evaluation PCB layout In order to make the most of the performance of this IC its PCB layout is very important Characteristics such as efficiency and ripple and the likes change greatly with layout patterns which please note carefully to Power Supply A Cin me SL SBD to Cathode of LED Y T KI T to Anode of each LED to GND Fig 42 Layout Connect the input bypath capacitor CIN 10OpF nearest to coil L as shown in the upper diagram Wire the power supply line by the low resistance from CIN to VBAT pin Thereby the input voltage ripple of the IC can be reduced Connect smoothing capacitor CREG of the regulator nearest to between VREG and GND pin as shown in the upper diagram Connect schottky barrier diode SBD of the regulator nearest to between coil L and switching transistor Tr And connect output capacitor COUT nearest to between CIN and GND pin Thereby the output voltage ripple of the IC can be reduced Connect switching transistor Tr nearest to SW pin Wire coil L and switching transistor Tr current sensing resistor Rsense by the low resistance Wiring to the SENSP pin isn t Tr side but connect it from Rsense side Over current value ma
9. a voltage lower than the power supply voltage or within the guaranteed value of electrical characteristics 10 Ground wiring pattern If small signal GND and large current GND are provided It will be recommended to separate the large current GND pattern from the small signal GND pattern and establish a single ground at the reference point of the set PCB so that resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of the small signal GND Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well 11 External capacitor In order to use a ceramic capacitor as the external capacitor determine the constant with consideration given to a degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature etc 12 Thermal shutdown circuit TSD When junction temperatures become 175 C typ or higher the thermal shutdown circuit operates and turns a switch OFF The thermal shutdown circuit which is aimed at isolating the LSI from thermal runaway as much as possible is not aimed at the protection or guarantee of the LSI Therefore do not continuously use the LSI with this circuit operating or use the LSI assuming its operation 13 Thermal design Perform thermal design in which there are adequate margins by taking into account the permissible dissipation Pd in actual states of use 14 Selection of coil Sel
10. above figure please insert about 220ohm in a signal line and apply current qualification Please confirm an internal pull down resistor in the block diagram and electrical property of P 5 www rohm com 9 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Attendance point of the restriction resistance input to RSTB 250 When the restriction resistance is input to RSTB it is necessary to 100 C consider the input current of RSTB 80 C The input current of RSTB changes that depending on the n power supply voltage and the temperature reference to Fig 33 200 q 25 C Because the temperature characteristic of the input current is shown in Fig 33 please choose resistance for which the voltage of the terminal can be guaranteed to 2 1V or more And it has the margin in the decision of resistance and please confirm and make sure it is no problem in a real application 30 C 150 100 RSTB input current uA BD6592MUV ae 50 Limit resistor FONS rel m RSTB 21 24 27 3 33 36 for RSTB terminal MEN RSTBIV Fig 33 RSTB terminal voltage RSTB inflow current At the time of the current driver six lines use RSTB inflow current The decision example of restriction resistance 1 When use the current driver of 6 parallel 2 9V to RSTB power supply restriction resistance value x 124yA 100 C input current gt 2 1V restriction resistance value lt
11. adapter etc Next the IC power supply is connected with a different coil power supply Under the conditions for inputting from 2 7V to 5 5V into IC VBAT please follow the recommend design in Fig 38 It connects VBAT terminal and VREG terminal together at IC outside When the coil power supply is applied it is no any problem even though IC power supply is the state of OV Although IC power supply is set to OV pull down resistance is arranged for the power off which cuts off the leak route from coil power supply in IC inside the leak route is cut off And there is no power on off sequence of coil power supply and IC power supply Coil Power supply 7V to 28V JL 10uF 4 7yH 10LED x 6 5i Pi t tt E a J I 20ooOocoHQ RTRO20NO05 sw FAILSEL SENSP SENSN Power ON OFF RSTB PWMDRV 200Hz PWMPOW pwm IC Power supply 2 7V to 5 5V Fig 42 Application at the time of power supply isolation www rohm com 2011 ROHM Co Ltd All rights reserved 14 25 ADANU ROLE BD6592MUV Technical Note The coil selection The DC DC is designed by more than 4 7uH When L value sets to a lower value it is possibility that the specific sub harmonic oscillation of current mode DC DC will be happened Please do not let L value to 3 3pH or below And L value increases the phase margin of DC DC becomes to zero Please enlarge the output capacitor value when you increase
12. regard for the digital block power supply and the analog block power supply even though these power supplies has the same level of potential separate the power supply pattern for the digital block from that for the analog block thus suppressing the diffraction of digital noises to the analog block power supply resulting from impedance common to the wiring patterns For the GND line give consideration to design the patterns in a similar manner Furthermore for all power supply terminals to ICs mount a capacitor between the power supply and the GND terminal At the same time in order to use an electrolytic capacitor thoroughly check to be sure the characteristics of the capacitor to be used present no problem including the occurrence of capacity dropout at a low temperature thus determining the constant 5 GND voltage Make setting of the potential of the GND terminal so that it will be maintained at the minimum in any operating state Furthermore check to be sure no terminals are at a potential lower than the GND voltage including an actual electric transient 6 Short circuit between terminals and erroneous mounting In order to mount ICs on a set PCB pay thorough attention to the direction and offset of the ICs Erroneous mounting can break down the ICs Furthermore if a short circuit occurs due to foreign matters entering between terminals or between the terminal and the power supply or the GND terminal the ICs can break down 7 Ope
13. 12 V x 2 0 41us 1 VIN VOUT x 1 fsw 0 69us gt Ton Peak current 12V 4 7pH x 0 41ys 1 05A When too large current is set output overshoot is caused be careful enough because it is led to break down of the IC in case of the worst G Operating of the application deficiency 1 When 1 LED or 1parallel OPEN during the operating In case of FAILSEL L the LED parallel which became OPEN isn t lighting but other LED parallel is lighting At that time output boosts up to the over voltage protection voltage 44 7V so that LED terminal may be OV or it boost to the output voltage that LED terminal voltage becomes LED terminal over voltage protection 11 5V or it becomes the output voltage restricted by the over current limit In case of FAILSEL H boost stops when LED becomes OPEN and all LED turns off the lights 2 When LED short circuited in the plural In case of FAILSEL L all LED is tumed on unless LED terminal voltage is LED terminal over voltage protection of more than 11 5V When it was more than 11 5V only the line which short circuited is turned on normally and LED current of other lines fall or turn off the lights In case of FAILSEL H boost stops at more than 11 5V and all LED turns off the lights 3 When Schottky diode came off Regardless of FAILSEL all LED isn t turned on Also IC and a switching transistor aren t destroyed because boost operating stops by the Schottky diode coming off protected function 4 When over current detection r
14. 163 0 6 0 3 0 23 0 03 Resistor for over current decision lt SENSP pin gt 47mO 1 ROHM MCR10EZHFSR047 2 0 1 25 0 55 0 1 SBD Pressure Manufacturer Product number Size Vertical Horizontal Height 60V ROHM RB160M 60 3 5 1 6 0 8 0 1 MOS FET Nch Pressure Manufacturer Product number YS No Height abus via 45V ROHM RTRO20NO05 2 8 2 9 1 0 2A 2 5V 60V ROHM RSSO65N06 6 0 5 0 1 75 6 5A 4 0V The coil is the part that is most influential to efficiency Select the coil whose direct current resistor DCR and current inductance characteristic is excellent BD6592MUV is designed for the inductance value of 4 7uH Don t use the inductance value less than 2 2UH Select a capacitor of ceramic type with excellent frequency and temperature characteristics Further select Capacitor to be used with small direct current resistance and pay sufficient attention to the PCB layout shown in P 16 About heat loss In heat design operate the DC DC converter in the following condition The following temperature is a guarantee temperature so consider the margin 1 Periphery temperature Ta must be less than 85 C 2 The loss of IC must be less than dissipation Pd www rohm com 17 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note OG Application example LED current setting controlled ISETH resistor 24kQ 20mA 16kO 30mA 12kO 40mA Brightness control Please input PWM pulse f
15. 2 1 4 VBAT V VBAT 5 0V EN terminal input current lin 8 3 14 0 pA Input 2 5V PWMPOW Terminal Low Input Voltage range PWML 0 0 2 V High Input Voltage range PWMH1 1 4 5 0 V VBAT gt 5 0V High Input Voltage range2 PWMH2 1 4 VBAT V VBAT 5 0V PWM pull down resistor PWMR 300 500 700 kQ RSTB Terminal Low Input Voltage range RSTBL 0 0 2 V High Input Voltage range1 RSTBH1 2 25 2 5 5 0 V VBAT gt 5 0V High Input Voltage range2 RSTBH2 2 25 2 5 VBAT V VBAT 5 0V Current Consumption IRSTB 89 134 pA RSTB 2 5V LED1 6 3V Regulator VREG Voltage VREG 4 0 5 0 6 0 V No load Under Voltage Lock Out UVLO 2 05 2 25 2 65 V Switching Regulator Quiescent Current 1 Iq1 0 6 3 4 pA RSTB 0V VBAT 12V Quiescent Current 2 Iq2 4 6 10 HA RSTB 0V VBAT 22V Current Consumption Idd 3 4 5 1 mA VDET 0V ISETH 24kO LED Control voltage VLED 0 4 0 5 0 6 V Over Current Limit voltage Ocp 70 100 130 mv SBD Open Protect Sop 0 1 V Detect voltage of VDET pin Switching frequency fSW 0 8 1 0 1 2 MHz Duty cycle limit Duty 92 5 95 0 99 0 LED1 6 0 3V Over voltage limit Ovi 43 0 44 7 46 4 V LED1 6 0 3V Current driver LED maximum current ILMAX 40 mA LED current accuracy ILACCU 5 ILED 30mA LED current matching ILMAT 3 Ede d LED1 6 ISET voltage Iset 0 5 0 6 0 7 V S dins ENDE LEDOVP 10 0 11 5 130 V RSTB PWMDRV 2 5V 1 This parameter is tested with DC measurement went FOIT dom 2 25 2011 06 Rev C 2011 ROHM Co Ltd All r
16. 2MUV Technical Note LED current setting range LED current can set up Normal and Starting setting current LED current can set up Normal current by resistance value RISETH connecting to ISETH voltage and LED current can set Starting current by resistance value RISETL connecting to ISETL voltage Setting of each LED current is given as shown below Normal current 20mA 24kO RISETH Starting constant current 0 6 RISET L Also Normal current setting range is 10mA 25mA Starting current setting range is OFF setting or 10A 100pA LED current can set OFF setting by open setting ISETL pin LED current becomes a leak current MAX 1pA at OFF setting ISETH Normal current setting example ISETL Starting current setting example RISETH LED current RISETL LED current 12kQ E12 40mA 6 2kO E24 97yA 16 kO E16 30mA 10kQ E6 60pA 24kOQ E24 20mA 47kQ E6 13pA 25 5 KQ E96 18 8mA 100 KQ E6 6yA 27 KQ E12 17 8mA 560 kO E12 1 190A 30kQ E24 16 0mA Connect to VREG pin OmA The separations of the IC Power supply and coil Power supply This IC can work in separating the power source in both IC power supply and coil power supply With this application it can obtain that decrease of IC power consumption and the applied voltage exceeds IC rating 22V That application is shown in below Fig 41 The higher voltage source is applied to the power source of coil that is connected from an
17. MDRV PWM ak ds I VBAT y 2 22V VBAT 1pF VREG 1C Powersupply T VREG mm LEDS ara GND GNDGND GND TEST ISETH ISETL LED6 Each 40mA HHH H 240mA zao 1 Can be set up to each90 240mA Fig 59 Fig 60 Can be set up to each15 40mA The separation of less than an IC power supply 5V and the coil power supply Coil Power supply 6 30V Battery pu 4 TyH 10LED x 6parallel Dot 2 2yF 2 2uF a RTRO20N05 sw T FAILSEL oe SENSP 51mQ S SENSN Power ON OFF RSTB PWMPOW LEDI LED2 PWMDRV LED3 VBAT LED4 VREG LED5 IC Powersupply T 2 2uF GND GND GND GND TEST ISETH ISETL epg Each 40mA Can be set up to each15 40mA www rohm com 2011 ROHM Co Ltd All rights reserved 22 25 201 NNO ROE BD6592MUV Application example of Analog dimming Control LED current to charged D A voltage Show application example and typ control Please decide final value after you evaluated application characteristic Battery J 10nF 5 4 TyH I 8LED x 6Parallel 2 2yF a RTRO20NO05 sw LI FALSEL og D A LED current 0 05V 19 4mA 0 2V 14 4mA Technical Note D A ISET voltage D A 24kQ Td Pino T E je SENEN 0 4V 7 7MA oe ee 0 5V
18. ROHM Technical Note SEMICONDUCTOR LED Drivers for LCD Backlights g Pb AN White Backlight LED Driver Iree RoHS for Medium to Large LCD Panels Switching Regulator Type BD6592MUV No 11040ECT33 G Description BD6592MUV is white LED driver IC with PWM step up DC DC converter that can boost max 42 5V and current driver that can drive max 40mA The wide and precision brightness can be controlled by external PWM pulse BD6592MUV has very accurate current drivers and it has few current errors between each strings So it will be helpful to reduce brightness spots on the LCD Small package type is suited for saving space G Features 1 High efficiency PWM step up DC DC converter fsw 1MHz max efficiency 93 2 High accuracy amp good matching 3 current drivers 6ch 3 Drive up to 12 in series 6 strings in parallel 272 white LEDs white LED Vf 3 5Vmax 4 Wide input voltage range 2 7V 22V 5 Rich safety functions Over voltage protection OVP Over current limit External SBD open detect Thermal shutdown 6 Small amp thin package VOFNO24V4040 4 0 x 4 0 x 1 0mm Applications All middle size LCD equipments backlight of Notebook PC portable DVD player car navigation systems etc G Absolute maximum ratings Ta 25 C Parameter Symbol Ratings Unit Condition TEST VREG SENSP SENSN SW Maximum applied voltage 1 VMAX1 7 V RSTB PWMPOW PWMDRV FAILSEL ISETH ISETL Maximum
19. ROHM Co Ltd All rights reserved Battery RTRO20N05 m 4 Dre E 82mQ 1T 4 7yH Technical Note 8LED x 2parallel 2 2yF 77 Sw SENSP FAILSEL SENSN ON OFF Power RSTB 100Hz 10kHz PWMPOW PWMDRV VBAT VREG L zal GND GND GND GND TEST ISETH ISETL Epg DIIS VDE LED1 LED2 LED3 LED4 LEDS a Each 120mA Can be set up to each45 120mA Fig 57 8 seriesx2 parallel LED current 120mA setting Current driver PWM application 21 25 2011 06 Rev C BD6592MUV Technical Note OG Application example LED current setting controlled ISETH resistor 24kQ 20mA 16kQ 30mA 12kQ 40mA Brightness control Please input PWM pulse from PWMPOW or PWMDRYV terminal Please refer electrical characteristic p 3 and function p 13 Ld Over 22V application For Big LED Current Coil Power supply Battery Easy ELT Jj 10uF 4 7uH 8LED x parallel PET 4 7uH 8LED x 6parallel De DF s t t t 2 2yF RTRO20N05 FAILSEL r4 RTRO20NO5 J SENSP 82mQ ETT FAILSEL SENSP 51m0 L SENSN n Power Power T ON OFF RSTB RSTB ON OFF TI b n PWMPOW v l 100Hz 10kHz PWMDRV 200Hz PW
20. RSTB 100Hz 1kHz PWMPOW PEDI doped PWMPOW LED RUM LED2 RM LED2 PWMDRV PWMDRV LED3 LED3 VBAT VBAT LED4 LED4 _ VREG LEDS VREG LEDS 2 2uF 2 2uF GND GND GND GND TEST ISETH ISETL Epg GND GND GND GND TEST ISETH ISETL gpg HHH H Each 40mA HHH H Each 80mA eee zaa Can be set up to each15 40mA Can be set up to each30 80mA Fig 52 4 seriesx6 parallel LED current 40mA setting Fig 53 8 seriesx3 parallel LED current 80mA setting Power control PWM application Power control PWM application pinch panel Battery Battery A Our 4 7uH 8LED x 2parallel 4 10HF 3 4 7uH 8LED x 2parallel DF De hom Tou T 2 2yF 2 2uF T RTRO20N05 sw RTRO20N05 sw a2 FAILSEL VDE FAILSEL VDE SENSP SENSP 82mQ I 82mQ i 7 SENSN 4M SENSN Power Power ON OFF RSTB ON OFF RSTB LL zu FWMPOW d 400Hz 1kHz PWMPOW LED 100Hz 10kHz T PWMDRV LEDE f iiis ANDRY LED2 PWM VBAT VBAT VREG LED5 VREG LED5 2 2uF 2 2uF GND GND GND GND TEST ISETH ISETL Epg GND GND GND GND TEST ISETH ISETL Epg Each 40mA Each 80mA Can be set up to each15 40mA Can be set up to each30 80mA Fig 54 8 seriesx2 parallel LED current 40mA setting Fig 55 8 seriesx2 parallel LED current 80mA setting Current driver PWM application Power control PWM
21. V Technical Note OG Application example LED current setting controlled ISETH resistor 24kQ 20mA 16kO 30mA 12kO 40mA Brightness control Please input PWM pulse from PWMPOW or PWMDRYV terminal Please refer electrical characteristic p 3 and function p 13 10 12inch panel Battery Battery J 10uF 3 4 7uH 7LED x 6parallel pi 10yF 3 4 7uH 10LED x 4parallel DF Dre e 2yF 2 2yF V VY a J RTR020N05 RTR020N05 EE FAILSEL FAILSEL SENSP SENSP 56mQ I 56m0 i i SENSN E SENSN ONOFF Tr RSTB OE RSTB PWMPOW PEDI PWMPOW LED1 I LED2 LED2 100Hz 10kHz PWMDRV 100Hz 10kHz PWMDRV PWM LED3 PWM LED3 VBAT VBAT LED4 T LEDA VREG VREG es LED5 zal LED5 GND GND GND GND TEST ISETH ISETL LED6 GND GND GND GND TEST ISETH ISETL LED6 HHH H Each 30mA HHH H Each 40mA ae zum Can be set up to each15 40mA Can be set up to each15 40mA Fig 48 7 seriesx6 parallel LED current 30mA setting Fig 49 10 seriesx4 parallel LED current 40mA setting Current driver PWM application Current driver PWM application inch panel Battery Battery A 10uF 4 7uH 8LED x 3parallel 4 Our 4 7uH 6LED x 4parallel DF Dt T 2 2yF 2 2uF T Sw SENSP RTRO20N05
22. application www rohm com 20 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV OG Application example LED current setting controlled ISETH resistor 24kQ 20mA 16kQ 30mA 12kQ 40mA Brightness control Please input PWM pulse from PWMPOW or PWMDRYV terminal Please refer electrical characteristic p 3 and function p 13 5inch panel Battery 4LED x 4parallel RTRO20N05 1OuF 4 T9H Jj 10u Power 2 2uF p ON OFF 2 100Hz 10kHz PWM GND GND GND GND TEST ISETH ISETL Epg n FAILSEL SENSP 7 SENSN RSTB PWMPOW mE I LED2 PWMDRV LED3 VBAT LED4 VREG LEDS ERE lt Each 40mA Can be set up to each30 80mA Fig 56 4 seriesx4 parallel LED current 40mA setting Battery 100F zy 100 a Current driver PWM application 4 7uH 3LED x 5parallel 22yF RTRO20NO5 sw mm FALSEL voe SENSP 82mQ I SENSN ml d ON OFF RSTB 100Hz 1kHz PWMPOW LED1 didi LED2 PWMDRV LED3 VBAT LED4 mH VREG LEDS 2 2uF GND GND GND GND TEST ISETH ISETL Epg LODS L TE a2 Each 40mA Can be set up to each15 40mA Fig 58 3 seriesx5 parallel LED current 40mA setting www rohm com Power control PWM application 2011
23. applied voltage 2 VMAX2 25 V T d LEDS CEDA LEDS Maximum applied voltage 3 VMAX3 50 5 V VDET Power dissipation 1 Pd1 500 mw Power dissipation 2 Pd2 780 mw Power dissipation 3 Pd3 1510 mw Operating temperature range Topr 30 85 C Storage temperature range Tstg 55 150 C 1 Reduced 4 0mW C With Ta gt 25 C when not mounted on a heat radiation Board 2 1 layer ROHM Standard board has been mounted Copper foil area Omm When it s used by more than Ta 25 C it s reduced by 6 2mW C 3 4 layer JEDEC Compliant board has been mounted Copper foil area 1layer 6 28mm Copper foil area 2 4layers 5655 04mm When it s used by more than Ta 25 C it s reduced by 12 1mW C Recommended operating range Ta 30 C 85 C Ratings ays Parameter Symbol Unit Condition Min Typ Max Power supply voltage VBAT 2 7 12 0 22 0 V www rohm com 1 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note G Electrical characteristic Unless otherwise specified VBAT 12V RSTB 2 5V Ta 25 C Parameter Symbol ome Unit Condition Min Typ Max FAILSEL PWMDRV Terminal EN threshold voltage Low VthL 0 0 2 V EN threshold voltage High 1 VthH1 14 5 0 V VBAT gt 5 0V EN threshold voltage High 2 VthH
24. connect to GND of IC GND Each GND is connecting inside IC but connect to GND of all board RSTB RSTB is used as a power supply of internal circuit So you mustn t input RSTB voltage with pull up resistor of several kO And please care about the relation between VBAT and RSTB enough ref P9 www rohm com 2011 ROHM Co Ltd All rights reserved 6 25 2011 06 Rev C BD6592MUV Technical Note Description of Functions 1 PWM current mode DC DC converter While BD6592MUV is power ON the lowest voltage of LED1 2 3 4 5 6 is detected PWM duty is decided to be 0 5V and output voltage is kept invariably As for the inputs of the PWM comparator as the feature of the PWM current mode one is overlapped with error components from the error amplifier and the other is overlapped with a current sense signal that controls the inductor current into Slope waveform to prevent sub harmonic oscillation This output controls external Nch Tr via the RS latch In the period where external Nch Tr gate is ON energy is accumulated in the external inductor and in the period where external Nch Tr gate is OFF energy is transferred to the output capacitor via external SBD BD6592MUV has many safety functions and their detection signals stop switching operation at once 2 Soft start BD6592MUV has soft start function The soft start function prevents large coil current Rush current at turning on is prevented by the soft start function After RSTB is cha
25. d any other information contained herein illustrate the standard usage and operations of the Products The peripheral conditions must be taken into account when designing circuits for mass production Great care was taken in ensuring the accuracy of the information specified in this document However should you incur any damage arising from any inaccuracy or misprint of such information ROHM shall bear no responsibility for such damage The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products ROHM does not grant you explicitly or implicitly any license to use or exercise intellectual property or other rights held by ROHM and other parties ROHM shall bear no responsibility whatsoever for any dispute arising from the use of such technical information The Products specified in this document are intended to be used with general use electronic equipment or devices such as audio visual equipment office automation equipment commu nication devices electronic appliances and amusement devices The Products specified in this document are not designed to be radiation tolerant While ROHM always makes efforts to enhance the quality and reliability of its Products a Product may fail or malfunction for a variety of reasons Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury fir
26. e or any other damage caused in the event of the failure of any Product such as derating redundancy fire control and fail safe designs ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed Scope or not in accordance with the instruction manual The Products are not designed or manufactured to be used with any equipment device or System which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury such as a medical instrument transportation equipment aerospace machinery nuclear reactor controller fuel controller or other safety device ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes If a Product is intended to be used for any such special purpose please contact a ROHM sales representative before purchasing If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law you will be required to obtain a license or permit under the Law Thank you for your accessing to ROHM product informations More detail product informations and catalogs are available please contact us ROHM ROHM Customer Support System SEMICONDUCTOR http www rohm com contact www rohm com 2011 ROHM Co Ltd All rights reserved R1120A
27. ect the low DCR inductors to decrease power loss for DC DC converter www rohm com 2011 ROHM Co Ltd All rights reserved 24 25 ADANU ROE BD6592MUV Technical Note Ordering part number ejs s Part No Part No Package Packaging and forming specification 6592 MUV VQFN024V4040 E2 Embossed tape and reel VQFNO024V4040 Tape and Reel information Tape Embossed carrier tape Quantity 2500pcs E2 Direction a in The direction is the 1pin of product is at the upper left when you hold reel on the left hand and you pull out the tape on the right hand 4 00 1 S 1 0MAX o O O O O le e pin Unit mm Order quantity needs to be multiple of the minimum quantity www rohm com 25 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved Notice Notes No copying or reproduction of this document in part or in whole is permitted without the consent of ROHM Co Ltd The content specified herein is subject to change for improvement without notice The content specified herein is for the purpose of introducing ROHM s products hereinafter Products If you wish to use any such Product please be sure to refer to the specifications which can be obtained from ROHM upon request Examples of application circuits circuit constants an
28. esistor came off Regardless of FAILSEL all LED isn t turned on Because the resistance of 100kO is between SENSP and SENSN terminal over current protection works instantly and LED current can t be flow G Control signal input timing 27V 5V Li L 1 VBAT 2 j D Min 100us 5V H EI 1 RSTB PWMPOW PWMDRV VREG DC DC VOUT Fig 31 Control signal timing Fig 32 Voltage with a control sign higher than VBAT Example corresponding to application of conditions In case you input control signs such as RSTB PWMPOW and PWMDRY in the condition that the standup of supply voltage VBAT is not completed be careful of the following point CD Input each control signal after VBAT exceeds 2 7V Please do not input each control sign until VBAT exceeds HI voltage of RSTB PWMPOW and PWMDRV 8 When you input RSTB during the standup of VBAT and HI voltage is inputted into PWMPOW please give the standup time to stable voltage as Min 100us 2 7V of VBAT There is no timing limitation at each input signal of RSTB PWMPOW and PWMDRV If each control sign changes into a condition lower than VBAT in 1 and 2 it goes via the ESD custody diode by the side of VBAT of each terminal A power supply is supplied to VBAT and there is a possibility of malfunctioning Moreover when the entrance current to the terminal exceeds 50mA it has possibility to damage the LSI In order to avoid this condition as shown in the
29. esistor connection for LED current setting at PWMDRV L A 11 PWMDRV In PWM input pin for power ON OFF only driver E 12 LED1 In Current sink for LED1 C 13 LED2 In Current sink for LED2 C 14 LED3 In Current sink for LED3 C 15 GND GND B 16 LED4 In Current sink for LED4 C 17 LED5 In Current sink for LED5 C 18 LED6 In Current sink for LED6 C 19 FAILSEL In Latch selectable pin of protect function E 20 GND GND B 21 RSTB In Reset pin L Reset H Reset cancel E 22 VREG Out Regulator output Internal power supply D 23 PWMPOW In PWM input pin for power ON OFF E 24 VBAT In Battery input C NWw FOPIT com 5 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV OG Application example Technical Note Battery Battery J 10pF 4 7uH 10LED x 6parallel T 10yF 4 7yH 10LED x 4aprallel 4 J gt Dt occ 22yF RTRO20N05 RTR020N05 Tl as FAILSEL VDE FAILSEL SENSP 47mQ I 47mQ T SENSN ONOFF TE RSTB ONOFF T RSTB PWMPOW LEDI PWMPOW LED T LED2 T LED2 200Hz PWMDRV 200Hz PWMDRV eam LED3 Pm I LED3 VBAT VBAT LED4 VREG dj VREG LEDS 2 2uF d 22yF GND GND GND GND TEST ISETH ISETL epg GND GND GND GND TEST ISETH ISETL Epg Z Each 40mA Each 40mA
30. f use Two techniques can be used as digital dimming by the PWM control One is PWM control of current driver the other is PWM control of power control As these two characteristics are shown in the below selects to PWM control process comply with application Efficiency emphasis in the low brightness which has an influence with the battery life gt 2 Power control PWM control LED current dispersion emphasis in the PWM brightness control gt 1 Current driver PWM control Reference PWM regulation process Efficiency of LED current 0 5mA PWM frequency 200Hz PWM Duty 2 5 Limit dispersion capability of low duty Current driver 7096 0 2 Power control 93 0 5 1 Current driver PWM control is controlled by providing PWM signal to PWMDRY as it is shown Fig 25 The current set up with ISETH is chosen as the Hi section of PWMDRV and the current is off as the Lo section Therefore the average LED current is increasing in proportion to duty cycle of PWMDRYV signal This method that it lets internal circuit and DC DC to work because it becomes to switch the driver the current tolerance is a few when the PWM brightness is adjusted it makes it possible to brightness control until 20us MINO 4 at 200Hz And don t use for the brightness control because effect of ON OFF changeover is big under 20us ON time and under 20us OFF time There is no effect of ON OFF changeover at 0 and 100 so there is no problem on use Typical PWM f
31. g condition In case of O Supply voltage of coil VIN O Inductance value of coil L O Switching frequency fsw MIN 0 8MHz Typ 1MHz MAX 1 2MHz Output voltage VOUT O Total LED current IOUT O Average current of coil lave O Peak current of coil Ipeak O Efficiency eff Please set up having margin it refers to data on p 3 O ON time of switching transistor Ton Ipeak VIN L x 1 fsw x 1 VIN VOUT lave VOUT x IOUT VIN eff Ton lave x 1 VIN VOUT x 1 fsw x L VIN x 2 Each current is calculated As peak current varies according to whether there is the direct current superposed the next is decided 1 VIN VOUT x 1 fsw lt Ton gt peak current Ipeak 2 lave 1 VIN VOUT x 1 fsw gt Ton gt peak current Ipeak www rohm com 8 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Example 1 In case of VIN 6 5V L 4 7uH fsw 1MHz VOUT 39V IOUT 80mA Efficiency 85 Ipeak 6 5V 4 7uH x 1 1MHz x 1 6 5V 39V 1 08A lave 39V x 80mA 6 0V 85 0 61A Ton 0 61A x 1 6 0V 39V x 1 1MHz x 4 7pH 6 0V x 2 0 90us 1 VIN VOUT x 1 fsw 0 85us lt Ton Peak current 1 08A 2 0 61A 1 15A Example 2 In case of VIN 12 0V L 4 7uH fsw 1MHz VOUT 39V IOUT 80mA Efficiency 85 Ipeak 12 0V 4 7yH x 1 1MHz x 1 12V 39V 1 77A lave 39V x 80mA 12 0V 85 0 31A Ton 0 31A x 1 12 V 39V x 1 1MHz x 4 7gH
32. ights reserved BD6592MUV Reference data 45 E 25 C 85 C 3 5 3 0 25 20 1 5 lin mA 1 0 0 5 0 0 0 2 4 6 8 10 12 14 16 18 20 22 VBAT V Fig 1 Current Consumption VBAT 50 25 0 25 50 75 100 Ta c Fig 4 UVLO Temperature LED current mA 0 10 20 30 40 50 60 70 80 90 100 Duty Fig 7 LED current PWMDRV HI Duty PWM 200Hz LED current mA 0 10 20 30 40 50 60 70 80 90 100 Duty Fig 10 LED current PWMPOW HI Duty PWM 200Hz www rohm com 2011 ROHM Co Ltd All rights reserved 6 85 C 1 30 C 0 2 4 6 8 10 12 14 16 18 20 22 VBATIV Fig 2 Quiescent current VBAT VBAT 12V 95 0 10 20 30 40 50 60 70 80 90 100 Duty Fig 5 Efficiency PWMPOW HI Duty ISETH 24kQ PWM 200Hz a 30 25 85 C 0 05 1 15 2 25 3 Duty Fig 8 LED current PWMDRV HI Duty Expansion PWM 200Hz Ta 30 25 85 C 0 0 5 1 1 5 2 25 3 Duty Fig 11 LED current PWMPOW HI Duty Expansion PWM 200Hz 3 25 Frequency MHz o o a 8 eo co o 100 95 90 85 80 Efficienc
33. nged L gt H when PWMPOW is changed L gt H soft start becomes effective for within 1ms and soft start doesn t become effective even if PWMPOW is changed L gt H after that And when the H section of PWMPOW is within ims soft start becomes invalid when PWMPOW is input to H more than three times The invalid of the soft start can be canceled by making RSTB gt L 3 FAILSEL pin When the error condition occurs boost operating is stopped by the protection function and the error condition is avoided On that occasion the way to stop of boost operating by the protection function can be selected with FAILSEL pin Details are as shown in Fig 29 30 After power ON when the protection function is operating under about 1ms have passed the stop state of the boost operating can be held through FAILSEL is H the stop state can reset through RSTB is L And boost operating is stopped when the protection function is operating through FAILSEL is L but when the protection function becomes un detect boost operating is started again It never keeps holding the stop state of boost operating In PWM control by PWMDRV can t use this function When it is off over 10ms on PWM control by PWMPOW using this function it may be stopped the boost operating as over current protection work at off on PWMPOW L DISCE of protect function is as shown below Over voltage protection External SBD open detect Thermal shutdown LED terminal over voltage protection Over cur
34. number of LED lines of the current driver and starting current setting at PWMDRV L related RSTB are hold 6 Over Current Limit Over current flows the current detection resistor that is connected to switching transistor source and between GND SENSP pin voltage turns more than detection voltage over current protection is operating and it is prevented from flowing more than detection current by reducing ON duty of switching Tr without stopping boost As over current detector of BD6592MUV is detected peak current current more than over current setting value does not flow And over current value can decide freely by changing over current detection voltage Derivation sequence of detection resistor Detection resistor Over current detection voltage Over current setting value TYP value of over current detection voltage is 100mV MIN 70mV and MAX 130mV and after the current value which was necessary for the normal operation was decided detection resistor is derived by using MIN value of over current detection value For example detection resistor when necessary current value was set at 1A is given as shown below Detection resistor 70mV 1A 70mQ MAX current dispersion of this detection resistor value is MAX current 130mV 70mQ 1 86A The estimate of the current value which need for the normal operation As over current detector of BD6592MUV is detected the peak current it have to estimate peak current to flow to the coil by operatin
35. of the coil changes owing to discharge of output capacitor It may flow to the over current limit value as follows Fig 34 Because soft start can be used when it turns off the lights with RSTB L The peak current of the coil can be suppressed as follows Fig 35 and this process of light off is recommended RSTB PWMDRV PWMPOW U LITI LILIT Output Voltage o pom o Current coil Fig 34 Light off control of PWMPOW pin at PWM control on PWM L RSTB PWMDRV PWMPOW Juuuuuuur Output Voltage Current coil Fig 35 Light off control of PWMPOW pin at PWM control on RSTB L www rohm com 11 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Start to use PWMDRV terminal for the PWM control PWM operating After RSTB and PWMPOW is changing L gt H input PWM to PWMDRYV terminal There is no constraint in turn of RSTB and PWMPOW When resistance is set as ISET after RSTB and PWMPOW is changing L gt H as follows Fig 36 when it is not input PWM to PWMDRY pin but input L boost of DC DC is unstable state because current driver doesn t pass current The starting current is pulled from each LED terminal and pressure up operating is stabilized to escape from this state Also the starting current can be set up by the resistance value connected to the ISETL terminal After starting as the starting current in PWM brightness control become useless the starting current is
36. ration in strong electromagnetic field Be noted that using ICs in the strong electromagnetic field can malfunction them 8 Inspection with set PCB On the inspection with the set PCB if a capacitor is connected to a low impedance IC terminal the IC can suffer stress Therefore be sure to discharge from the set PCB by each process Furthermore in order to mount or dismount the set PCB to from the jig for the inspection process be sure to turn OFF the power supply and then mount the set PCB to the jig After the completion of the inspection be sure to turn OFF the power supply and then dismount it from the jig In addition for protection against static electricity establish a ground for the assembly process and pay thorough attention to the transportation and the storage of the set PCB 9 Input terminals In terms of the construction of IC parasitic elements are inevitably formed in relation to potential The operation of the parasitic element can cause interference with circuit operation thus resulting in a malfunction and then breakdown of the input terminal Therefore pay thorough attention not to handle the input terminals such as to apply to the input terminals a voltage lower than the GND respectively so that any parasitic element will operate Furthermore do not apply a voltage to the input terminals when no power supply voltage is applied to the IC In addition even if the power supply voltage is applied apply to the input terminals
37. re as shown below External SBD open detect In the case of external SBD is not connected to IC the coil or external Tr may be destructed Therefore at such an error as VOUT becoming 0 1V or below the Under Detector shown in the figure works and turns off the output Tr and prevents the coil and the IC from being destructed And the IC changes from activation into non activation and current does not flow to the coil 0mA Over voltage protection At such an error of output open as the output DC DC and the LED is not connected to IC the DC DC will boost too much and the VDET terminal exceed the absolute maximum ratings and may destruct the IC Therefore when VDET becomes sensing voltage or higher the over voltage limit works and turns off the output Tr and the pressure up made stop At this moment the IC changes from activation into non activation and the output voltage goes down slowly And when the output voltage becomes the hysteresis of the over voltage limit or below the output voltage pressure up to sensing voltage once again and unless the application error is recovered this operation is repeated 5 Thermal shut down BD6592MUV has thermal shut down function The thermal shut down works at 175 C or higher and the IC changes from activation into non activation Because non activation is different from RSTB L it doesn t be reset inside IC Moreover even if thermal shut down function works soft start FAILSEL selection the
38. rent limit lt When it is off on PWMPOW gt lt FAILSEL H gt Rie _______ ____ __ PWMDRV__ gt PWMPOW Output voltage RSTB ET about 1ms FAILSEL un operating range Protection un detection function X etection un detection i F i Coil current ake d d pde i H i FAILSEL r normal operating i boost stop off DX normal operating s invalid X valid y function Boost off 1 1 1 1 1 1 1 1 1 1 1 1 1 i 1 i operating i lt FAILSEL L gt lt When it is off on RSTB gt RSTB RB PWMDRV 39 PWMPOW LITT DT Output i i about 1ms 1 FAILSEL L iun operating renga voltage i 1 T 7 i T Protection un detectio Idetection X un detection function i t t H 1 1 i f Coil current H invalid i i Boost normal operating Eus normal FAILSEL operating H f H function Fig 29 FAILSEL operating description Fig 30 FAILSEL H light off control www rohm com 7 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note 4 External SBD open detect and over voltage protection BD6592MUV has over boost protection by external SBD open and over voltage protection It detects VDET voltage and is stopped output Tr in abnormal condition Details a
39. requency is 100Hz 10kHz When resistance is set as ISET RSTB sets H gt L so the starting current may be effective after RSTB sets L gt H it becomes PWM of the starting current and PWM of ISETH setting current to PWM two times PWMDRV ON OFF I i 1 LED current y ON OFF n i IH 1 a Coil current ON OFF i l t IC s active current i i ON i Fig 39 2 Power control PWM control is controlled by providing PWM signal to PWMPOW as it is shown Fig 27 The current setting set up with PWMDRY logic is chosen as the Hi section and the current is off as the Lo section Therefore the average LED current is increasing in proportion to duty cycle of PWMPOW signal This method is because IC can be power off at off time the consumption current can be suppress and the high efficiency can be available so it makes it possible to brightness control until 50us MIN1 at 200Hz And don t use for the brightness control because effect of power ON OFF time changeover is big under 50us ON time and under 50us OFF time There is no effect of ON OFF changeover at 0 and 100 so there is no problem on use Typical PWM frequency is 100Hz 1kHz Also PWM can t control RSTB and PWMPOW at the same time After RSTB sets H control PWM only PWMPOW PWMPOW ON OFF LED current 7 ON OFF Coil current ON OFF IC s active curret ON om Fig 40 www rohm com 13 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD659
40. rom PWMPOW or PWMDRY terminal Please refer electrical characteristic p 3 and function p 12 15inch panel Battery A 10uF 4 7uH 10LED x 6parallel RTRO20NO5 FAILSEL PWMPOW LED2 100H2 10kHz PWMDRV PWM LED3 VBAT I 2 2uF 1 GND GND GND GND TEST ISETH ISETL LED6 Each 40mA Can be set up to each15 40mA Fig 45 10 seriesx6 parallel LED current 40mA setting Current driver PWM application 13 14inch panel Battery Battery A 10uF 4 7uH 8LED x 6parallel 4 Our 4 7uH 8LED x 6parallel DF D t t T 2 2uF 2 2yF 2 2uF T P RTRO20N05 RTRO20N05 LJ sw FAILSEL SN FAILSEL SENSP SENSP 51mo I 51mQ SENSN 4M SENSN ON OFF T RSTB ON OFF RSTB 100Hz 1kHz PWMPOW PWMPOW PWM I PWMDRV 100Hz 10kHz PWMDRV PWM VBAT VBAT me VREG VREG 22yF Each 40mA Each 40mA Can be set up to each15 40mA Can be set up to each15 40mA Fig 46 8 seriesx 6 parallel LED current 40mA setting Fig 47 8 seriesx6 parallel LED current 40mA setting Power control PWM application Current driver PWM application www rohm com 18 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MU
41. select LED current driver BD6592MUV can control the IC system by RSTB and IC can power off compulsory by setting 0 2V or below Also It powers on PWMPOW is at more than 1 4V and RSTB is at more than 2 25V When RSTB PWMPOWG H ISETH current is selected at PWMDRV H and ISETL current is selected at PWMDRV L The starting current in PWMDRV L sets OFF second time rise of PWMDRV and it becomes OmA setting after that After RSTB sets L once the starting current can be flowed again by changing it to H RSTB PWMPOW PWMDRV IC LED current H L L Off OFF H H L On Starting current decided with ISETL H L H Off OFF H H H On Current decided with ISETH L L H L H Off OFF www rohm com 10 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Start to use PWMPOW terminal for the PWM control PWM operating After RSTB and PWMDRY is changing L gt H input PWM to PWMPOW terminal There is no constraint in turn of RSTB and PWMDRV And because it corresponds to PWM drive of shorter ON time than soft start time 1ms when PWMPOW is input H more than three times the soft start is invalidated and it enable to correspond the high speed drive Until RSTB is set L invalidation of the soft start isn t canceled In case of lighting gt light off gt lighting when it turns off the lights with PWMc L and It starts without soft start when it sets PWM modulated light again But the peak current
42. set up OmA at the second rise time of PWMDRV automatically as follows Fig 37 In case of lighting gt light off gt lighting when it turns off the lights with PWM L and It starts without soft start because of soft start period was end when it sets PWM modulated light again But the peak current of the coil changes owing to discharge of output capacitor It may flow to the over current limit value as follows Fig 37 Because soft start can be used when it turns off the lights with RSTB L The peak current of the coil can be suppressed as follows Fig 38 and this process of light off is recommended RST LI EN a a aO L1 C E PWMPOW L H L H L H L PWMDRV dn P P x Output voltage LED pin Current driver of 4 1 starting current PWMDRV j TTE 11171 Output Voltage Current coil Fig 37 Light off control of PWMDRV pin at PWM control on PWM L RSTB PWMPOW PWMDRV Output Voltage Current coil Fig 38 Light off control of PPWMDRV pin at PWM control on RSTB L www rohm com 12 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Brightness control There are two dimming method is available first method is analog dimming that apply analog voltage to ISET terminal and second method is PWM control via digital dimming of PWMPOW or PWMDRV Because each method has the different merit please choose a suitable method for the application o
43. y 75 70 65 60 N N eo a o LED Current mA a L LED Current mA Technical Note 25 C 30 C 0 2 4 6 8 10 12 14 16 18 20 22 VBAT V Fig 3 Oscillation frequency VBAT VBAT 12V 0 10 20 30 40 50 60 70 80 90 100 Duty 5 Fig 6 Efficiency PWMDRV HI Duty ISETH 24kQ PWM 200Hz 0 10 20 30 40 50 60 70 80 90 100 Duty Fig 9 ED current PWMDRV HI Duty PWM 200Hz 1kHz 10kHz 200Hz 10kHz 1kHz 0 10 20 30 40 50 60 70 80 90 100 Duty Fig 12 LED current PWMPOW HI Duty PWM 200Hz 1kHz 10kHz 2011 06 Rev C BD6592MUV Technical Note Ss ou Ed M 4 PWMDRV DM 1 Ky Max Matching Max LED Current Average Current Matching Max LED Current Average Current 1 o S VOUT t E E i 350mV 9 2 BI i 5 5 i 2 3 LED Current Min Matching 7 Min LED Current Average Current o Min Matching Min LED Current Average Current 10mAv div lo E rere 0 20 40 60 80 10096 0 2 4 6 8 10 en ET cA ASIE 200mV M20 0us A Chl 240V PWM HI Duty PWM HI Duty Fig 13 Fig 14 Fig 15 LED current matching PWMDRV HI Duty LED current matching PWMDRV HI Duty VOUT response PWM
44. y become low when wiring from Tr side Connect Rsense of GND side isolated to SENS pin Don t wire between Rsense and SNESN pin wiring from Rsense pin to GND pin And Rsense GND line must be wired directly to GND pin of output capacitor It has the possibility that restricts the current drive performance by the influence of the noise when other GND is connected to this GND Connect LED current setting resistor RISET nearest to ISET pin There is possibility to oscillate when capacity is added to ISET terminal so pay attention that capacity isn t added And RISET of GND side must be wired directly to GND pin When those pins are not connected directly near the chip influence is given to the performance of BD6592MUV and may limit the current drive performance As for the wire to the inductor make its resistance component small so as to reduce electric power consumption and increase the entire efficiency The layout pattern in consideration of these is shown in next page www rohm com 15 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Recommended PCB layout pattern BD6592MUV Fig 44 Rear surface lt Top view gt www rohm com 16 25 2011 06 Rev C 2011 ROHM Co Ltd All rights reserved BD6592MUV Technical Note Selection of external parts Recommended external parts are as shown below When to use other parts than these select the following equivalent parts
Download Pdf Manuals
Related Search
ROHM BD6592MUV handbook