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Global Mixed-mode Technology G923 handbook

1. Gui Global Mixed mode Technology Inc 923 300mA High PSRR LDO Regulators Features Low 90pA No Load Supply Current Guaranteed 300mA Output Current Dropout Voltage is 200mV 150mA Load PSRR 65dB 120Hz Over Temperature Protection and Short Circuit Protection Two Modes of Operation Fixed Mode 1 50V 5 00V Adjustable Mode from 1 25V to 5 50V Max Supply Current in Shutdown Mode lt 1pA Low Output Noise at 224uUV pens Stable with low cost ceramic capacitors Applications Notebook Computers Cellular Phones PDAs Digital still Camera and Video Recorders Hand Held Devices Audio Codec Pin Configuration SOT 23 5 Ver 1 1 Jan 19 2006 General Description The G923 is a low supply current high PSRR and low dropout linear regulator that comes in a space saving SOT 23 5 package The supply current at no load is 9OLA In the shutdown mode the maximum supply current is less than 1A Operating voltage range of the G923 is from 2 50V to 5 50V The over current protection limit is set at 550mA typical An over tem perature protection circuit is built in in the G923 to prevent thermal overload These power saving fea tures make the G923 ideal for use in the bat tery powered applications such as notebook com puters cellular phones and PDA s The G923 has two modes of operation When the SET pin is connected to ground its output is a pre set value 1 50V 5 00V There is no external component need
2. 2006 http www gmt com tw
3. higher so that the PMOS output transistor has a smaller gate to source voltage Ves This reduces the current carrying capa bility of the PMOS output transistor as a result the output voltage decreases until the feedback voltage is equal to 1 25V Similarly when the feedback voltage is less than 1 25V the error amplifier causes the output PMOS to source more current to pull the feedback SHUTDOWN LOGIC OVER TEMP PROTECT voltage up to 1 25V Thus through this feedback ac tion the error amplifier output PMOS and the voltage dividers effectively form a unity gain amplifier with the feedback voltage force to be the same as the 1 25V bandgap reference The output voltage Vour is then given by the following equation Vout 1 25 1 R1 R2 1 Alternatively the relationship between R1 and R2 is given by R1 R2 Vou 1 25 1 2 For the reasons of reducing power dissipation and loop stability R2 is chosen to be 100K For G923 330 R1 is 164K and the pre set VOUT is 3 30V When external voltage divider is used as shown in Figure 2 the SET pin voltage will be larger than 350mV The non inverting input of the amplifier will be connected to the external voltage divider However the operation of the feedback loop is the same so that the conditions of Equations 1 and 2 are still true The output voltage is still given by Equation 1 OVER CURRENT PROTECT amp DYNAMIC FEEDBACK MODE COMPARATOR Figure 1 Func
4. 00mA DIV FUN TNT UM IAE NEN NS S NE NIS I NS ER a RON E NR NES EN WS SN NS GR E NE IN NE IR NA NUN NE RN am INE E RE Chi Ee 500mV SM4 00ms A Ch2 2 34 V Ver 1 1 Jan 19 2006 Ripple Rejection dB er Hu UM AM l ae TAE TL Li L ee O asla a u HX Chi 5 00 V MR 2 00 v MW 100ms A Chi 5 30V Ch4 100mA Qh Ripple Rejection K OV C OUT 448mV 1uF ripple pk pk 10 100 1000 10000 100000 Frequency Hz TEL 886 3 5788833 http www gmt com tw Shuntdown Pin Delay Tek Run T C WT Global Mixed mode Technology Inc Typical Performance Characteristics continued if 500 400 ViN75V CiN 1uF Courz1uF IL 150mA H Shutdown Delay CH2 Vour CH1 SHDN Dropout vs lo Chi 1 00V wQ 2 00 V M 200gs A Chl 700mV 300 200 Drop out mV 100 Recommended Minimum Footprint 4 2mm Ver 1 1 Jan 19 2006 150 200 lo mA SOT 23 5 We c o G923 Shuntdown Pin Delay Tek Prevu i Trig af ViN 5V CiN 1uF Courz1uF IL 150mA _ Shutdown Delay CH2 Your nite inesoinssnleteslessslenssinm wshandhurrlooaal alana hanhanhunkuantuahaahuahunhahooch a WOOO VOVO VOOG UO wiwa lesen 1 u u Q Uu U UU UQ UL u u U U Chi 1 00 V wU 2 00 V 5M 200s A Chl X 740mV TEL 886 3 5788833 http www gmt com tw Pin Description Cm Global Mixed mode
5. 3 http www gmt com tw Layout Guide An input capacitance of 1uF is required between the G923 input pin and ground the amount of the capaci tance may be increased without limit This capacitor must be located a distance of not more than 1cm from the input and return to a clean analog ground Input capacitor can filter out the input voltage spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board s rout ing wire Otherwise the actual voltage at the IN pin may exceed the absolute maximum rating Gui Global Mixed mode Technology Inc 923 The output capacitor also must be located a distance of not more than 1cm from output to a clean analog ground Because it can filter out the output spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board s rout ing wire Figure 6 is adjustable mode of G923 PCB layout Figure 7 is a PCB layout of G923 fixed mode SOT23 5 100mil 1 60mil Figure 3 Recomme nded Minimum Footprint Safe Operating Area of G923 Power Dissipation Limit 200 Maximum Recommended Outp ut Current lt 9 1A 25 C TA 55 C 0 E A TA 85 C PO L Ta 25 C Still Air 1oz Copper m SOT 23 5Package O Mourted on recommended mimimum footprint R 9J A 240 C W 0 00 05 10 15 20 25 30 35 40 45 Input Outpu
6. Limits is 100 production tested at Ta 25 C Low duty pulse techniques are used during test to maintain junc tion temperature as close to ambient as possible Note 2 Guaranteed by line regulation test Note 3 Adjustable mode only Note 4 Not tested For design purposes the current limit should be considered 400mA minimum to 650mA maximum Note 5 The dropout voltage is defined as Vin Vout when Vou is 100mV below the target value of Vour The performance of every G923 part see Typical Performance Characteristics Ver 1 1 TEL 886 3 5788833 Jan 19 2006 http www gmt com tw G923 WT Global Mixed mode Technology Inc Typical Performance Characteristics Vin BV Vour 3 3V CiN 1HF Cour 1pF TA225 C unless otherwise noted Load Transient Tek Run es mm Line Transient o o Tek Run u Cin 1uF Cour 1uF Tr 10us Tr 10us l 10mA N CH2 Vout CH1 VIN OFFSET 4 5V ch KIT MCh2 20 0mV M39 Dus A Chi 7 4 72V Chi 100mA ONE 20 omv ASIMI40 ous A Chi Z 102mA Short Circuit Current Start Up Bkstp L TekRun _ Bee Mw 6V CmeTuF CoumuR 00000000000 Loi Git CouretuF CH4 It CH2 van M 200ms A Chr F 5 30 V eg 100mA C25 Overcurrent Protection Characteristics T u Vin 6 0V CiN 1uF Cours1uF Tek Run AlqjAui009 eBeyoA 3nd3no Output Current 1
7. Technology Inc G923 PIN NAME FUNCTION Ground This pin also functions as a heatsink Solder to large pads or the circuit board ground plane to maxi EE SHON Active Low Shutdown Input A logic low reduces the supply current to less than 1A Connect to IN for normal opera tion mize thermal dissipation Regulator Input Supply voltage can range from 2 5V to 5 5V Bypass with 1uF to GND Regulator Output Fixed or adjustable from 1 25V to 5 5V Sources up to 300mA Bypass with a 1uF 0 2 typical ESR capacitor to GND 5 SET Feedback Input for Setting the Output Voltage Connect to GND to set the output voltage to the preset output voltage Connect to an external resistor divider for adjustable output operation Detailed Description The block diagram of the G923 is shown in Figure 1 It consists of an error amplifier 1 25 V bandgap reference PMOS output transistor internal feedback voltage divider mode comparator shutdown logic over current protec tion circuit and over temperature protection circuit The mode comparator compares the SET pin voltage with an internal 350mV reference If the SET pin volt age is less than 350mV the internal feedback voltage divider s central tap is connected to the non inverting input of the error amplifier The error amplifier com pares non inverting input with the 1 25V bandgap ref erence If the feedback voltage is higher than 1 25V the error amplifier s output becomes
8. arge fast transients are anticipated and the device is lo cated several inches from the power source Power Supply Rejection and Operation from Sources Other than Batteries The G923 is designed to deliver low dropout voltages and low quiescent currents in battery powered sys tems Power supply rejection is 65dB at low frequen cies As the frequency increases above 20kHz the output capacitor is the major contributor to the rejec tion of power supply noise When operating from sources other than batteries improve supply noise rejection and transient response by increasing the values of the input and output ca pacitors and using passive filtering techniques Load Transient Considerations The G923 load transient response graphs show two components of the output response a DC shift of the output voltage due to the different load currents and the transient response Typical overshoot for step changes in the load current from 10mA to 300mA is 8mV Increasing the output capacitor s value and de creasing its ESR attenuates transient spikes Input Output Dropout Voltage A regulator s minimum input output voltage differential or dropout voltage determines the lowest usable sup ply voltage In battery powered systems this will de termine the useful end of life battery voltage Because the G923 use a P channel MOSFET pass transistor their dropout voltage is a function of Rosco multiplied by the load current TEL 886 3 578883
9. ature soldering 10sec 260 C Note 9 See Recommended Minimum Footprint Figure 3 Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied Exposure to absolute maximum rating conditions for extended periods may affect device reliability Electrical Characteristics Vin 3 6V V san Vin Ta T 25 C unless otherwise noted Note 1 Reg eg sss Input Voltage Note 2 ain Il uM C j Eeer dM Iis Maxam Oupucuren dmep Pi Current Limit Note f we ff 00 50 ma lout 300mA SET GND Vin V stp 0 1V to 5 5V lout 10MA Load Regulation Lie rz10mAto300mA 002 mmal Ripple Rejection L PSRR Fc100Hz O45Veslo il0mA 65 a SHUTDOWN E Ve Regulatorenabled 15 MEME Vu_ Regulator shutdown o4 M wama gg Ea Cars Shutdown Supply Curent ken Man z y s oz 1 m SET INPUT Vin 2 5V to 5 5V Ta 25 C 1 225 SET Reference Voltage Note 3 VsetT 1mA our TA Tmn t0 Tis e Pa SET Input Leakage Current Note 3 EUR 1 3V Ta 425 C 5 30 na THERMAL PROTECTION Thermal Shutdown Temperature Tsw C 4 4 4 4 4 4 s Thermal Shutdown Hysteresis L tze 5 C Note 1
10. ed to decide the output voltage When an output other than the preset value is needed two external resistors should be used as a voltage divider The output volt age is then decided by the resistor ratio The G923 comes in a space saving SOT 23 5 package OUTPUT VOLTAGE OUTPUT VOLTAGE Cour 1uF Adjustable mode TEL 886 3 5788833 http www gmt com tw Gui Global Mixed mode Technology Inc 923 Ordering Information ORDER ORDER NUMBER NUMBER Pb free an VOLTAGE TEMP RANGE PACKAGE G923 330T1U G923 330T1Uf 92AUx 3 30V 40 C 85 C SOT 23 5 23 5 For other output voltage please contact us at sales gmt com tw Note T1 SOT 23 5 U Tape amp Reel Selector Guide Z Sr ES o9 NUMBER Pb free VOLTAGE EE 180 9 G923 190T1U G923 190T1U f Ver 1 1 TEL 886 3 5788833 Jan 19 2006 http www gmt com tw Gui Global Mixed mode Technology Inc 923 Absolute Maximum Ratings Continuous Power Dissipation Ta 25 C Vito GND 0 3V to 7V Hl SN Output Short Circuit Duration Infinite Operating Temperature Range 40 C to 85 C SET to GND ll LL LLL 0 3V to 7V Junction Temperature 150 C SHDNto CND ee A acc a SOTSZSSD oma dor a7 A09 ee GA RE R 240 C Watt SHDN tO TIN suc aee es RO oec x 7V to 0 3V Storage Temperature Range 65 C to 160 C OUT to GND 6 6 ee 0 3V to Vin 0 3V Reflow Temper
11. or its power dissipa tion is always given by P lout Vin Vout The maxi mum power dissipation is given by Pouva T Ta 0 34 150 C 25 C 240 C W 520mW Where T T4 is the temperature difference the G923 die and the ambient air Ou is the thermal resistance of the chosen package to the ambient air For surface Ver 1 1 Jan 19 2006 C WT Global Mixed mode Technology Inc VOLTAGE G923 mount device heat sinking is accomplished by using the heat spreading capabilities of the PC board and its copper traces In the case of a SOT 23 5 package the thermal resistance is typically 240 C Watt See Rec ommended Minimum Footprint Figure 3 Refer to Figure 4 is the G923 valid operating region Safe Op erating Area amp refer to Figure 5 is maximum power dissipation of SOT 23 5 The die attachment area of the G923 s lead frame is connected to pin 2 which is the GND pin Therefore the GND pin of G923 can carry away the heat of the G923 die very effectively To improve the maximum power providing capability connect the GND pin to ground using a large ground plane near the GND pin Applications Information Capacitor Selection and Regulator Stability Normally use a 1uF capacitor on the input and a Lut capacitor on the output of the G923 Larger input ca pacitor values and lower ESR provide better sup ply noise rejection and transient response A higher value input capacitor LOUF may be necessary if l
12. t Voltage Differential Vi Vou V Note Vinay lt 9 9V Figure 4 Safe Operating Area Figure 6 Adjustable Mode Distance between pin amp capacitor must no more than 10m Ver 1 1 Jan 19 2006 Maximum Power Dissipation of SOT 23 5 SS TT Still Air 0 6 1o copper on SOT 23 5 Package Mounted on recommended foorprint R 34 240 C W 0 5 0 4 0 3 0 2 Power Dissipation W 2 35 45 5 65 7 85 95 105 115 125 Amibent Temperature Ta C Figure 5 Power Dissipation vs Tem perature Figure 7 Fixed Mode Distance between pin amp capacitor must no more than 10m TEL 886 3 5788833 http www gmt com tw Gui Global Mixed mode Technology Inc 923 Package Information lt 91 Note 1 Package body sizes exclude mold flash protrusions or gate burrs 2 Tolerance 0 1000 mm 4mil unless otherwise specified 3 Coplanarity 0 1000mm 4 Dimension L is measured in gage plane SYMBOL on ww DIMENSION IN INCH O e ewsqv e uw j as ee mme 0 102 0 110 0 118 0 015 rv s Lu D o 5 PACKAGE Q TYIREEL SOT 23 5 3 000 ea Feed Direction SOT 23 5 Package Orientation GMT Inc does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and GMT Inc reserves the right at any time without notice to change said circuitry and specifications Ver 1 1 TEL 886 3 5788833 Jan 19
13. tional Diagram Ver 1 1 Jan 19 2006 TEL 886 3 5788833 http www gmt com tw OUTPUT Figure 2 Adjustable Output Using External Feedback Resistors Over Current Protection The G923 uses a current sense resistor to monitor the output current A portion of the PMOS output transis tors current is mirrored to a resistor such that the voltage across this resistor is proportional to the output current Once the output current exceeds limit thresh old G923 would be protected with a limited output current Further more when the output is short to ground the output current would be folded back to a less limit Over Temperature Protection To prevent abnormal temperature from occurring the G923 has a built in temperature monitoring circuit When it detects the temperature is above 145 C the output transistor is turned off When the IC is cooled down to below 120 C the output is turned on again In this way the G923 will be protected against abnormal junction temperature during operation Shutdown Mode When the SHDN pinis connected a logic low voltage the G923 enters shutdown mode All the analog cir cuits are turned off completely which reduces the current consumption to only the leakage current The G923 output pass transistor would get into high im pedance level There is an internal discharge path to help to shorten discharge delay time Operating Region and Power Dissipation Since the G923 is a linear regulat

Global Mixed-mode Technology G923 handbook

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