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CIRRUS LOGIC 16-4 SA56

1. 0 10 20 30 40 50 60 70 Va V 5V Supply Current l p vs Frequency 00615 lt 00610 00605 00600 00595 00590 C 50 100 150 200 250 300 350 Frequency kHz DUC vs Analog Input Supply Current lpp 80 AOUT Duty Cycle ol 20 BOUT oO 1 2 3 Analog Input V Maximum Duty Cycle for Hingar Operation in Analog Mode N Duty Cycle 0 100K 200K 300K 400K Frequency kHz 5V Supply Current I vs Supply Voltage V 5 85 5 8 5 75 lv MA 5 7 5 65 5 6 Supply Current V vs Temperature 20 Supply Current mA 0 10 20 30 40 50 60 70 Vs V s 23 kHz 50 DUC Vop 5V 50 0 50 100 H gt A A Frequency Hz N w O m m N Wm o 0 Aa Diode Forward Current I A oO 00 1K 10K Cow pF Clamp Diode Forward Voltage Drop 0 0 5 1 1 5 Temperature C Frequency vs C ywu Diode Forward Voltage V V supply Current I vs Frequency 12 10 08 06 04 Supply Current A 02 0 0 50 100 150 200 250 300 350 Frequency kHz 5V Supply Current V p vs Temperature 7 loo m
2. The digital PWM input signal is applied to the DIR pin as shown in Figure 4 and the PWM pin is tied HIGH to Vpp Both pairs of output MOSFETs will switch in a locked complementary fashion With a 50 duty cycle the average voltage of outputs Aout and Boyz will be the same which is half of V so that the average differential voltage over each period applied to the load will therefore be zero Four quadrant operation allows for smooth transitions through zero current for low speed applications However power dissipation is slightly higher than in two quadrant opera tion since all four output MOSFETs must switch every cycle Vpp Vs ci ce kes mi 5 4 wuah fey Voo Tum sc 16 4 5 19 20 DIR YA 4519 20 18 DISABLE 24 22 Motor 9 11 Aout Saal FAULT SA56 Bout 2 3 7 Voo O gt gt Pwo 9 10 15 SIG REF 1 23 2 12 Pend O a Cpwm Isen _ I L Rsense FIGURE 4 4 QUADRANT DIGITAL MODE BRAKING DIGITAL MODE Under digital control the SA56 can rapidly decelerate the motor by shunting the winding currents through the output MOSFETs Logic LOW on the PWM input both A and B out puts high The motor winding current circulates through the on resistance of the MOSFETs quickly slowing the motor The winding current can be monitored with the Isen pin during the braking of the motor However the current during braking circulates in the normal forward direction through on
3. digital inputs In the analog mode the capacitor from Cry to SlGeyp sets the frequency of an internal triangular ramp sig nal See Figure 2 An analog voltage applied to the PWM pin is compared to a 2 5 volt reference within the SA56 thereby governing the duty cycle of the output Note that the analog pin DIR pin 16 is connected to signal ground SIGgq Voo Vs ci G 6s a huh im zal Vpp LIM 16 nip vs 45 19 20 v 18 DISABLE ot pp Motor Yu FAULT od 23 SA56 Bour l2 Analog Control 17 oun Voltage 1 4V PWM SIG 210 o VREF 1 23 1 z 12 CPwM l ae SEN 8 Ti Rsense v FIGURE 2 4 QUADRANT ANALOG OPERATION OPERATING WITH DIGITAL INPUTS Two and 4 quadrant operation are possible with the SA56 when driven with a digital PWM signal from a microcontroller or DSP When using a digital modulation signal tie the Cpwm pin to SIGsasp to disable the internal oscillator and ramp generator When operating in the digital mode pulse widths should be no less than 100 ns and the switching frequency should remain less than 500 kHz This will allow enough time for the output MOSFETs to reach their full on and off states before receiving a command to reverse state 2 QUADRANT DIGITAL MODE Two quadrant operation of the FETs is realized by driving PWM pin 17 of the SA56 with a digital PWM signal supplied by a microcontroller or DSP as depicted in
4. Figure 3 When using a digital modulation signal connect the Cpwm pin to SlGgnp to disable the internal oscillator and its companion ramp generator A digital PWM signal applied to the PWM pin controls the output duty cycle at one output pin while the other output pin is held HIGH The input at the DIR pin Vpp or SIGgup governs the output behavior If DIR is a logic HIGH the Aour output will be held high and the Boy output will be switched as the complement of the PWM input signal The average output at Aour Will always be greater than at Bour Whereas if DIR is a logic LOW the Boy output will be held HIGH and the Aour output will be switched Operating in two quadrant mode reduces switching noise and power dissipation but limits the ability to control the motor at very low speed Vop Vs C1 C2 c3 v V 13 14 7 16 Vo Tum Sam 5 19 20 Vos OF SIG G5 O 1 DIR 18 DISABLE ot 99 Motor vi Aout pi FAULT SA56 Bout 2 3 z gt gt PWM sia 940 15 GND VnzF 1 23 12 Peno gt e N v T Cewm sen L Ti om FIGURE 3 2 QUADRANT DIGITAL MODE nia MICROTECHNOLOGY CORPORATION 9 5980 NORTH SHANNON ROAD 9 TUCSON ARIZONA 85741 USA 9 APPLICATIONS HOTLINE 1 800 546 2739 OPERATING CONSIDERATIONS SA56 4 QUADRANT DIGITAL MODE During four quadrant operation a single digital PWM input includes magnitude and direction information
5. PWM control or 1 4V analog input for duty cycle control in analog control mode Following a fault pulling the DISABLE pin HIGH and then LOW will reset a latched fault condition When pulled HIGH all four output MOSFETs are disabled A logic LOW on this pin allows the four output FETs to function normally When the DISABLE and FAULT pins are tied to a microcontroller the FAULT pin will generate an interrupt in the microcontroller so that the interrupt can in turn generate a pulse on the DISABLE pin When a fault occurs the SA56 fault circuitry will be reset Half bridge output A APEX MICROTECHNOLOGY CORPORATION 9 TELEPHONE 520 690 8600 9 FAX 520 888 3329 ORDERS 520 690 8601 9 EMAIL prodlit apexmicrotech com 5 OPERATING CONSIDERATIONS SA56 MODES OF OPERATION The following chart shows the 3 modes of operation Cowm PWM DIR Aout Bout pin 12 pin 17 pin 16 pins 21 23 pins 2 3 Low SlGenp Analog control Control voltage Control voltage voltage greater than Vger greater than Vper 1 4V Aour Bour lt 0 Bour Aour gt 0 average average voltage voltage 2 Quadrant Digital Mode Modulation In High Voo High V PWM FSi aup Modulation in Low SiG PWM Figh Va Quadrant Digtal Mode High Vo Modulated in DR Dn _ Connect ca pacitor to set frequency 2 Quadrant Analog Mode 4 QUADRANT ANALOG MODE The SA56 can operate in 4 quadrant mode with analog or
6. prevent erratic low efficiency operation and excessive ringing at the outputs Electrolytic capacitors at least 10 uF per output ampere are required for suppressing Vs to Ponp noise High quality ceramic capacitors X7R 1 F or greater should also be used Only ca pacitors rated for switching applications should be considered The bypass capacitors must be located as close to the power supply pins as possible Due to the very fast switching times of the outputs the inductance of 1 inch of circuit trace could cause noticeable degradation in performance The bypassing requirements of Vpp are less stringent but still necessary A 0 1 uF to 0 47 uF capacitor connected directly between the Vos and SlGg np pins will suffice PIN DESCRIPTIONS Pin Name Description 1 23 Ponp Power high current ground return path of the motor 23 Bor Half bridge output B 4 5 Vs High voltage supply 19 20 6 sc The short circuit protection circuits will sense a direct short from either output Aour or Bour to Ponp Or Vs as well as across the load If the high current protection circuit engages it will place all four MOSFETs in the tristate state high impedance output The SC output pin 6 will go HIGH though not latch thereby denoting that this protection feature has been triggered 7 Tum Temperature limit CMOS This pin can be used as a flag for an over temperature con dition Under normal operation this pin will 8 Isen 9 10 SlGenp 11 F
7. A V 60V 23 kHz 50 DUC V 5 V 5 50 0 50 100 Temperature C Cowm VS Foy at Varying Temperatures PWM M fo A 10K Frequency Hz 100 1K 10K Coa pF Load Current vs Total On Resistance 0 525 a N 00 515 0 51 0 505 a 0 495 Total On Resistancs me P P and N Chan at 100 DUC 0 485 0 1 2 3 4 5 Load Current A APEX MICROTECHNOLOGY CORPORATION 9 TELEPHONE 520 690 8600 e FAX 520 888 3329 ORDERS 520 690 8601 EMAIL prodlit apexmicrotech com 3 SA56 TYPICAL PERFORMANCE GRAPHS 05 loan vs R ON loan vs lense 0 45 RosON 125 C R ON 125 C 0 4 3 0 35 Ni 6 03 lt 0 25 5 R ON 25 C z g 0 2 R gON 0 C 0 DUC lense B 0 15 R ON 50 C 0 1 R ON 85 C 0 05 0 100 DUC for N Channel 0 1 2 3 4 los A lisab A l oan lsense vs loan loan sense RATIO vs loan 0 DUC loans B 7 100 DUC I A 2 4 l vs 25 C Varying Temperatures 100 DUC A SENSE Varying Temperatures 0 DUG
8. AULT 12 Crwm 13 14 Voo 15 VREF 16 DIR 17 PWM 18 DISABLE 21 22 Aour be logic low When a junction temperature exceeds approximately 160 C this pin will change to logic high and the output will be latched off Grounding this pin disables over temperature protection This pin should be left open if over temperature protection is desired but the flag is not used Current Sense output and programmable current limit A current proportional to the output current is sourced by this pin Typi cally this pin is connected to a resistor for programmable current limit or transconduc tance operation Ground connection for all internal digital and low current analog circuitry This pin latches high whenever the four MOSFETs have been placed in the tristate condition which occurs when either the high current or the thermal protection has engaged An external timing capacitor is connected to this pin to set the frequency of the internal oscillator and ramp generator for analog control mode The capacitor value pF 4 05x107 Fey where Fey the desired switching frequency This pin is grounded for digital control mode 5V supply for input logic and low voltage analog circuitry Reference voltage Can be used at low cur rent for biasing analog loop circuits Direction of rotation control In 2 quadrant digital control determines the active output FETs This pin should be grounded in analog control mode CMOS TTL input for digital
9. Isense B 1 2 3 4 5 0 1 2 3 4 5 lao A los A conn lsense RATIO vs oao Vier Vs TEMPERATURE 2 495 25 C 2 494 oc 2 493 SESC 2 492 50 C 2 491 2 49 I 2 489 125 C gt 2488 2 487 2 486 100 DUC Igense A 2 485 2 484 1 2 3 4 5 40 20 0 20 40 60 80 100 lLoap A Temperature C APEX MICROTECHNOLOGY CORPORATION 9 5980 NORTH SHANNON ROAD e TUCSON ARIZONA 85741 USA 9 APPLICATIONS HOTLINE 1 800 546 2739 4 OPERATING CONSIDERATIONS SA56 GENERAL Please read SA56 Design Ideas that covers the various SA56 applications in considerable detail Also see Application Note 1 General Operating Considerations which covers stabil ity power supplies heat sinking mounting and specification interpretation Visit www apexmicrotech com for design tools that help automate tasks such as calculations for stability internal power dissipation current limit heat sink selection Apex s complete Application Notes library Technical Seminar Workbook and Evaluation Kits GROUND PINS The two SIGsap pins 9 amp 10 are for input signal grounds Pins 1 and 23 Ponp are power grounds The Penn amp SlGenp pins are connected at one point inside the IC It is also recom mended the user connectboth pins ata single pointon the board in a way that no current flows through that connection POWER SUPPLY BYPASSING Bypass capacitors to power supply terminals Vs and Vpp must be connected physically close to the pins to
10. PULSE WIDTH MODULATION AMPLIFIER SA56 amp MICROTECHNOLOGY HTTP WWW APEXMICROTECH COM 800 546 APEX 800 546 2739 FEATURES DELIVERS UP TO 5A CONTINUOUS OUTPUT OPERATES AT SUPPLY VOLTAGES UP TO 60V NO SHOOT THROUGH CURRENT e THERMAL SHUTDOWN OUTPUTS OFF AT 160 C SHORTED LOAD PROTECTION to V or Poy or SHORTED LOAD NO BOOTSTRAP CAPACITORS REQUIRED e PROGRAMMABLE ONBOARD PWM APPLICATIONS 23 PIN SIP e DC BRUSH TYPE MOTOR DRIVES e POSITION AND VELOCITY SERVOMECHANISMS FACEA SELEBES e FACTORY AUTOMATION ROBOTS DESCRIPTION e NUMERICALLY CONTROLLED MACHINERY The SA56 is a5 ampere PWM Amplifier designed for motion e COMPUTER PRINTERS AND PLOTTERS control applications The device is built using a multi technology process that combines bipolar and CMOS control circuitry with DMOS power devices in a single monolithic structure Ideal for driving DC and stepper motors the SA56 accommodates peak output currents up to 10 amperes An innovative circuit that facilitates low loss sensing of the output current has been implemented An on board PWM oscillator and comparator are used to convert an analog signal into PWM direction of rotation and magnitude for motor control applications TTL or CMOS digital inputs allow direct external control in 2 quadrant or 4 quadrant modes FIGURE 1 BLOCK DIAGRAM Voo Vs 5V lt 60V l SA56 gt Pulse Wi
11. UT lour 1A 180 240 300 pA lour 5A 79 1 0 1 32 mA CURRENT SENSE LINEARITY ERROR 1A lt lour lt 5A 1 5 100 MA lt lour lt 5A 8 5A lt lour lt 10A Peak Currents only 8 SHUTDOWN TEMPERATURE T sp Outputs Turn OFF 160 C QUIESCENT SUPPLY CURRENT ls No Load Fgy 100kHz 50 DUC 26 50 mA QUIESCENT SUPPLY CURRENT lpp No Load Fgy 100kHz 50 DUC 6 15 mA OUTPUT TURN ON DELAY TIME t No Load 200 ns OUTPUT TURN ON SWITCHING TIME t No Load 41 ns OUTPUT TURN OFF DELAY TIMES tpoti No Load 272 ns OUTPUT TURN OFF SWITCHING TIME t No Load 46 ns MINIMUM INPUT PULSE WIDTH t No Load 140 ns DIGITAL MODE REFERENCE VOLTAGE Iker IMA 2 3 2 5 2 7 V Vref OUTPUT CURRENT Vref 2 5V Iper Source Only No current sink capability 1 mA ANALOG INPUT RANGE FOR Load Current 400pA 1 4 V FULL MODULATION HIGH CURRENT SHUTDOWN RESPONSE Output shorted 250 800 ns No bypass capacitor at SCin pin THERMAL RESISTANCE Junction to Case Full Temperature Range 1 C W RESISTANCE Junction to Air Full Temperature Range 12 21 C W TEMPERATURE RANGE Case 40 125 G NOTE These specifications apply for V 50V and V 5V at 25 C unless otherwise specified APEX MICROTECHNOLOGY CORPORATION 9 5980 NORTH SHANNON ROAD TUCSON ARIZONA 85741 USA 9 APPLICATIONS HOTLINE 1 800 546 2739 2 TYPICAL PERFORMANCE GRAPHS SA56 Supply Current I vs Supply Voltage V 16
12. ak the over current circuit tristates so that the four MOSFETs go into a latched fault condition Thermal protection The thermal protection circuits will en gage if the temperature of any of the four MOSFETs reaches approximately 160 C If this occurs the FAULT output pin will go HIGH If the thermal protection circuit engages it will place all four MOSFETs in the tristate state high impedance output The T u output which is normally LOW will go HIGH though not latch thereby denoting which of the protection features has been triggered PROGRAMMABLE CURRENT LIMIT The lsen pin sources a current proportional to the forward output current of the active P channel output MOSFET The proportionality is approximately 200 microamperes per ampere of output current Note that the Ise output is blocked during the switching transitions when current spikes are likely to be significant To create a programmable current limit connect a resistor from Isen to SIGgnp If the voltage across this resistor exceeds an internally generated 2 75V threshold all four output MOS FETs will be turned off for the remainder of the switching cycle A 2 7k Ohm resistor will set the current limit at approximately 5 amperes The Ise Output can also be used for maintaining a current control loop in torque motor applications CURRENT SENSE LINEARITY CALCULATION The current sense linearity is specified in the table on page 2 and is calculated using the metho
13. d described below a Define a straight line y mx b joining the two end data points where m is the slope and b is the offset or zero crossover Calculate the slope m and offset c using the extreme data points Assume lsenge in the y axis and I gap in the x axis b Calculate linear Icey or ideal lsense value ISipeaL using the straight line equation derived in step a for the gap data points c Determine deviation from linear len step b and actual measured Isense Value IS ctya_ as Shown below IS Linearity Error DEAL IS cCruAL x 100 IDEAL This data sheet has been carefully checked and is believed to be reliable however no responsibility is assumed for possible inaccuracies or omissions All specifications are subject to change without notice SA56U REV A FEBRUARY 2007 2007 Apex Microtechnology Corp
14. dth Modulation Amplifier P Coy Tt 12 PWM gt 17 Q1 a3 DISABLE 18 ra gt DIR 16 gt Control logic i 21 22 ai Gate Drive Aout len 8 q gt and 2 3 B v 15 PWM Generator Control Pour REF FAULT 11 Q2 Q4 Tum 7 Lai lt SC 16 x l l l APEX MICROTECHNOLOGY CORPORATION 9 TELEPHONE 520 690 8600 9 FAX 520 888 3329 e ORDERS 520 690 8601 EMAIL prodlit apexmicrotech com 1 SA56 ABSOLUTE MAXIMUM RATINGS SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS SUPPLY VOLTAGE Vpp 5 5V SUPPLY VOLTAGE Vs 60V PEAK OUTPUT CURRENT 100mS 10A CONTINUOUS OUTPUT CURRENT 5A POWER DISSIPATION 125W POWER DISSIPATION T 25 C Free Air 10W JUNCTION TEMPERATURE Timax 150 C ESD SUSCEPTIBILITY Logic Pins Only 1500V STORAGE TEMPERATURE Tsrs 40 C to 150 C LEAD TEMPERATURE Soldering 10 sec 300 C JUNCTION TEMPERATURE T 40 C to 150 C SPECIFICATIONS PARAMETER TEST CONDITIONS MIN TYP MAX UNITS Vs 12 60 V VDD 4 5 5 5 V SWITCH ON RESISTANCE Ros ON Output Current 5A 0 23 0 6 O N Channel SWITCH ON RESISTANCE Ros ON Output Current 5A 0 27 0 6 O P Channel CLAMP DIODE FORWARD DROP Vcu vp Clamp Current 5A 1 43 V LOGIC LOW INPUT VOLTAGE Vj 0 5 0 8 V LOGIC LOW INPUT CURRENT li Vin 0 1V 10 10 pA LOGIC HIGH INPUT VOLTAGE Vi 2 Vop V LOGIC HIGH INPUT CURRENT li Vin 5 5V 10 10 pA CURRENT SENSE OUTP
15. e output MOSFET and is in the reverse in the other MOSFET The current sense feature can measure only forward currents The logic input on the DIR pin dictates which output MOSFET is used for sensing the forward current during braking PROTECTION CIRCUITS The most severe condition for any power device is a direct hard wired screwdriver short from an output to ground While the short circuit protection will latch the output MOSFETs within 500 ns typical the die and package may be required to dissipate up to 500 Watts of power until the protection circuits are activated This energy can be destructive particularly at higher operat ing voltages so sound thermal design is critical if fault tolerance is to be established in the design The Vs and Penp pins may become very hot during this period of high current Thermal and short circuit protection are included in the SA56 to prevent damage in the event that faults occur as described below Short circuit protection The short circuit protection circuits will sense a direct short from either output Aour or Bour to Ponp Or Vs as well as across the load If the high current protection circuit engages it will place all four MOSFETs in the tristate state high impedance output The SC output pin 6 will go HIGH though not latch thereby denoting that this protection feature has been triggered Over current protection When the current on the high side goes above 10 amperes pe

CIRRUS LOGIC 16-4 SA56

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