discontinued product for reference onl y. use udn2917eb for new design the a2918swh and a2918swv motor drivers are designed to drive both windings of a bipolar stepper motor or bidirectionally control two dc motors. all bridges are capable of sustaining 45 v and include internal pulse-width modulation (pwm) control of the output current to 1.5 a. for pwm current control, the maximum output current is determined by the user? selection of a reference voltage and sensing resistor. a phase input to each bridge determines load current direction. active low enable inputs control the four drivers in each bridge. the bridges include both ground clamp and flyback diodes for protection against inductive transients. internally generated delays prevent cross-over currents when switching current direction. special power-up sequencing is not required. thermal protection circuitry disables the outputs if the chip temperature exceeds safe operating limits. the a2918swh/v are supplied in an 18-lead power-tab package with staggered lead forming. the tab is internally insulated from the device and requires no external isolation. the a2918swh/v are available for operation from -40 c to +85 c. to order, change the suffix from 's? to 'e?. these devices are also available on special order for operation to +125 c. features 1.5 a continuous output current 45 v output sustaining voltage internal pwm current control low output saturation voltage internal clamp diodes internal thermal shutdown circuitry similar to dual pbl3718 or dual pbl3770 dual full-bridge pwm motor driver absolute maximum ratings at t j +150 c motor supply voltage, v bb . . . . . . . . . 45 v output current, i out (t w 20 s) . . 1.75 a (continuous) . . . . . . . . . . . . . . 1.5 a logic supply voltage, v cc . . . . . . . . . 7.0 v logic input voltage range, v in . . . . . . . . . . . . . . . -0.3 v to +7.0 v output emitter voltage, v e . . . . . . . . . 1.5 v package power dissipation, p d . . . . . . . . . . . . . . . . . . . . see graph operating temperature range, t a . . . . . . . . . . . . . . . . -20 c to +85 c storage temperature range, t s . . . . . . . . . . . . . . . -40 c to +150 c output current rating may be limited by duty cycle, ambient temperature, and heat sinking. under any set of conditions, do not exceed the specified peak current rating or a junction temperature of +150 c. always order by complete part number: part number application a2918swh for horizontal mount a2918swv for vertical mount v ref v cc v bb 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 1 2 pwm 1 pwm 2 tsd dwg. pp-051 out 1a out 1b out 2a out 2b e 1 e 2 sense 1 sense 2 ground reference logic sply load sply enable 1 enable 2 rc 1 rc 2 phase 1 phase 2 data sheet 29319.24a 2918
2918 dual full-bridge pwm motor driver 115 northeast cutoff, box 15036 worcester, massachusetts 01615-0036 (508) 853-5000 functional block diagram truth table enable phase out a out b lhhl lllh hxzz x = dont care z = high impedance v ref v cc out 1a out 1b out 2a out 2b e 1 e 2 sense 1 sense 2 ground reference logic supply load supply enable 1 enable 2 rc 1 rc 2 phase 1 phase 2 v bb 1 + one shot source disable 10 + source disable 10 2 one shot pwm 1 pwm 2 tsd 18 16 12 14 13 117 5 2 4 15 10 3 6 8 7 9 11 r t r s r s r t r c c t c t c c r c c c dw g . fp-033 50 75 100 125 150 10 6 4 2 0 allowable package power dissipation in watts temperature in c 8 25 dwg. gp-043 r = 28 c /w j a r = 9 c/w j t w copyright ? 1991, 1993, allegro microsystems, inc.
2918 dual full-bridge pwm motor driver www.allegromicro.com electrical characteristics at t a = +25 c, v bb = 45 v, v cc = 4.75 v to 5.25 v, v ref = 5.0 v (unless otherwise noted). limits characteristic symbol test conditions min. typ. max. units output drivers (out a or out b ) motor supply range v bb 10 45 v output leakage current i cex v out = v bb <1.0 50 a v out = 0 <-1.0 -50 a output sustaining voltage v ce(sus) i out = 1.5 a, l = 3.0 mh 45 v output saturation voltage v ce(sat) sink driver, i out = +1.0 a 0.7 0.8 v sink driver, i out = +1.5 a 0.9 1.1 v source driver, i out = -1.0 a 1.8 2.0 v source driver, i out = -1.5 a 1.9 2.2 v clamp diode leakage current i r v r = 45 v <1.0 50 a clamp diode forward voltage v f i f = 1.5 a 1.6 2.0 v driver supply current i bb(on) both bridges on, no load 12 15 ma i bb(off) both bridges off 8.0 10 ma control logic input voltage v in(1) all inputs 2.4 v v in(0) all inputs 0.8 v input current i in(1) v in = 2.4 v <1.0 20 a i in(0) v in = 0.8 v -3.0 -200 a reference voltage range v ref operating 1.5 v cc v current limit threshold v ref /v sense at trip point 9.5 10 10.5 thermal shutdown temp. t j 170 c total logic supply current i cc(on) v en = 0.8 v, no load 105 140 ma i cc(off) v en = 2.4 v, no load 10 12 ma negative current is defined as coming out of (sourcing) the specified device pin. typical data is for design information only.
2918 dual full-bridge pwm motor driver 115 northeast cutoff, box 15036 worcester, massachusetts 01615-0036 (508) 853-5000 pwm output current waveform applications information pwm current control the a2918swh/v dual bridges are designed to drive both windings of a bipolar stepper motor. output current is sensed and controlled independently in each bridge by an external sense resistor (r s ), an internal comparator, and an internal monostable multivibrator. when the bridge is turned on, current increases in the motor winding and it is sensed by r s until the sense voltage (v sense ) reaches the level set at the comparator s input: i trip = v ref /10 r s the comparator then triggers the monostable which turns off the source driver of the bridge. the actual load current peak will be slightly higher than the trip point (especially for low-inductance loads) because of internal logic and switching delays. this delay (t d ) is 2 s typically. after turn-off, the motor current decays, circulating through the ground clamp diode and sink transistor. the source driver s off time t off , and therefore the magnitude of the current decrease, is determined by the monostable s external rc timing components, where t off = r t c t within the range of 20 k ? to 100 k ? and 200 pf to 500 pf. when the source driver is re-enabled, the winding current (the sense voltage) again is allowed to rise to the comparator s threshold. this cycle repeats itself, maintaining the average motor winding current at the desired level. special circuitry has been included to prevent runaway current control when t off is set too short. this circuitry prevents the source driver from being re-enabled until the load current has decayed to below the i trip level. loads with high distributed capacitances may result in high turn-on current peaks. this peak, appearing across r s , will attempt to trip the comparator, resulting in possible erroneous current control or high-frequency oscillations. an external r c c c low-pass filter may be used to delay the action of the comparator, and thus ignore turn-on spikes. + 0 dwg. wm-003-1a v phase i out t d t off i trip
2918 dual full-bridge pwm motor driver www.allegromicro.com load current paths general to avoid excessive voltage spikes on the load supply pin (v bb ), a large-value capacitor ( 47 f) should be connected from v bb to the ground pin as close as possible to the device. under no circumstances should the voltage at v bb exceed 45 v. the phase input to each bridge determines the direction motor winding current flows. an internally generated deadtime, of approximately 3 s, prevents crossover currents that can occur when switching the phase input. all four drivers in the bridge output can be turned off, with v en 2.4, resulting in a fast current decay through the internal ground clamp and flyback diodes. the fast current decay is desirable in half-step and high-speed applications. the enable input must be tied low if it is not used. varying the reference voltage (v ref ) provides continuous control of the peak load current. thermal protection circuitry turns off all drivers when the junction temperature reaches approximately +170 c. it is intended only to protect the device from failures due to excessive junction temperature and should not imply that output short circuits are permitted. the output drivers are re-enabled when the junction temperature cools to approximately +145 c. dwg. ep-006-1 r s bb v bridge on source off all off the products described here are manufactured in japan by sanken electric co., ltd. for sale by allegro microsystems, inc. sanken electric co., ltd. and allegro microsystems, inc. reserve the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of their products. therefore, the user is cautioned to verify that the information in this publication is current before placing any order. these products are not authorized for use as critical components in life-support appliances, devices, or systems without express written approval. the information included herein is believed to be accurate and reliable. however, sanken electric co., ltd. and allegro microsystems, inc. assume no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
2918 dual full-bridge pwm motor driver 115 northeast cutoff, box 15036 worcester, massachusetts 01615-0036 (508) 853-5000 1 18 1.228 1.213 0.066 0.016 0.637 0.623 0.196 0.182 0.126 x 0.150 dwg. mp-006 in 0.968 0.953 0.070 0.063 0.022 0.033 0.022 0.131 0.120 0.519 0.504 0.397 0.382 0.091 0.083 0.260 0.213 0.318 0.272 0.141 0.095 0.204 0.158 0.086 0.040 0.653 0.638 1.240 1.225 a2918swh for horizontal mounting dimensions in inches (for reference only) dimensions in millimeters (controlling dimensions) notes: 1. exact body and lead configuration at vendor? option within limits shown. 2. lead spacing tolerance is non-cumulative. 1 18 16.6 16.2 31.2 30.8 31.5 31.1 1.68 0.4 16.2 15.8 5.0 4.6 3.2 x 3.8 dw g . mp-006 mm 24.6 24.2 1.8 1.6 0.57 0.54 0.85 0.55 3.35 3.05 ? 13.2 12.8 2.3 2.1 6.6 5.4 8.1 6.9 3.6 2.4 5.2 4.0 2.2 1.0 10.1 9.7
2918 dual full-bridge pwm motor driver www.allegromicro.com a2918swv for vertical mounting dimensions in inches (for reference only) dimensions in millimeters (controlling dimensions) notes: 1. exact body and lead configuration at vendor? option within limits shown. 2. lead spacing tolerance is non-cumulative. 118 0.653 0.638 1.228 1.213 1.240 1.225 0.066 0.027 0.637 0.623 0.196 0.182 0.185 0.130 0.126 x 0.150 dw g . mp-004 in 0.968 0.953 0.070 0.063 0.022 0.033 0.022 0.131 0.120 ? 0.104 0.089 0.519 0.504 0.283 0.245 0.421 0.363 0.397 0.382 118 16.6 16.2 31.2 30.8 31.5 31.1 1.68 0.7 16.2 15.8 5.0 4.6 4.7 3.3 3.2 x 3.8 dw g . mp-004 mm 24.6 24.2 1.8 1.6 0.57 0.54 0.85 0.55 3.35 3.05 ? 7.2 6.2 2.65 2.25 13.2 12.8 10.7 9.2 10.1 9.7
2918 dual full-bridge pwm motor driver 115 northeast cutoff, box 15036 worcester, massachusetts 01615-0036 (508) 853-5000 motor drivers function output ratings* part number ? integrated circuits for brushless dc motors 3-phase power mosfet controller 28 v 3933 3-phase power mosfet controller 50 v 3932 3-phase power mosfet controller 50 v 7600 2-phase hall-effect sensor/driver 400 ma 26 v 3626 bidirectional 3-phase back-emf controller/driver 600 ma 14 v 8906 2-phase hall-effect sensor/driver 900 ma 14 v 3625 3-phase back-emf controller/driver 900 ma 14 v 8902Ca 3-phase controller/drivers 2.0 a 45 v 2936 & 2936-120 integrated bridge drivers for dc and bipolar stepper motors dual full bridge with protection & diagnostics 500 ma 30 v 3976 pwm current-controlled dual full bridge 650 ma 30 v 3966 pwm current-controlled dual full bridge 650 ma 30 v 3968 pwm current-controlled dual full bridge 750 ma 45 v 2916 pwm current-controlled dual full bridge 750 ma 45 v 2919 pwm current-controlled dual full bridge 750 ma 45 v 6219 pwm current-controlled dual full bridge 800 ma 33 v 3964 pwm current-controlled full bridge 1.3 a 50 v 3953 pwm current-controlled dual full bridge 1.5 a 45 v 2917 pwm current-controlled microstepping full bridge 1.5 a 50 v 3955 pwm current-controlled microstepping full bridge 1.5 a 50 v 3957 pwm current-controlled dual dmos full bridge 1.5 a 50 v 3972 dual full-bridge driver 2.0 a 50 v 2998 pwm current-controlled full bridge 2.0 a 50 v 3952 dmos full bridge pwm driver 2.0 a 50 v 3958 dual dmos full bridge 2.5 a 50 v 3971 unipolar stepper motor & other drivers voice-coil motor driver 500 ma 6 v 8932Ca voice-coil motor driver 800 ma 16 v 8958 unipolar stepper-motor quad drivers 1 a 46 v 7024 & 7029 unipolar microstepper-motor quad driver 1.2 a 46 v 7042 unipolar stepper-motor translator/driver 1.25 a 50 v 5804 unipolar stepper-motor quad driver 1.8 a 50 v 2540 unipolar stepper-motor quad driver 1.8 a 50 v 2544 unipolar stepper-motor quad driver 3 a 46 v 7026 unipolar microstepper-motor quad driver 3 a 46 v 7044 * current is maximum specified test condition, voltage is maximum rating. see specification for sustaining voltage limits or over-current protection voltage limits. negative current is defined as coming out of (sourcing) the output. ? complete part number includes additional characters to indicate operating temperature range and package style. also, see 3175, 3177, 3235, and 3275 hall-effect sensors for use with brushless dc motors.
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