apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ????????????????????????????????? ??????????????????? ??????? ????? ????? ? ? ? ?? ?? ?? ??? ?? ??? ?? ??? ?? ??? ?? ?? ???????? ???????? ???? ? ? ? ? ???? features ? low cost ? wide common mode range includes negative supply ? wide supply voltage range single supply: 5v to 40v split supplies: 2.5v to 20v ? high efficiency |vsC2.2v| at 2.5a typ ? high output current 3a ? low distortion applications ? half & full bridge motor drivers ? audio power amplifier stereo 30w rms per channel bridge 60w rms per package ? ideal for single supply systems 5v peripherals, 12v automotive 28v avionic description the ampli?er design consists of dual monolithic input and output stages to achieve the desired input and output characteristics of the PA74 and pa76. the input stage utilizes a dual power op amp on a single chip monolithic that drives the output stages. the output stages are con?gured in a non inverting unity gain buffer con?guration. the output stages of the ampli?er are also compensated for stability. the PA74 and pa76 dual ampli?ers are designed with both monolithic and hybrid technologies providing a cost effective solution for applications requiring multiple ampli - ?ers per board or bridge mode con?gurations. both ampli?ers are internally compensated but are not recommended for use as unity gain followers. this dual hybrid circuit utilizes a beryllia (beo) substrate, thick ?lm resistors, ceramic capacitors and monolithic ampli?ers to maximize reliability and power handling capability, minimize size and give top performance. ultrasonically bonded aluminum wires provide reliable interconnections at all operating temperatures. the 8-pin to-3 package is hermetically sealed and electrically isolated. the use of compressible isolation washers voids the warranty. equivalent schematic one channel ? ? ? ? ? ? ? ? ? ?? ? ?????? ?????? ?????? ?????? ?? ? ?????? ?????? ? ? ? ? ? ? ? ? ? ? ? ?? ? ?????? ?????? ?????? ?? ? ?????? ?????? ?????? ? ? ? ? typical application r1 and r2 set up ampli?er a in a non-inverting gain of 2.8. amp b is set up as a unity gain inverter driven from the output of amp a. note that amp b inverts signals about the reference node, which is set at mid-supply (14v) by r5 and r6. when the command input is 5v, the output of amp a is 14v. since this is equal to the reference node voltage, the output of amp b is also 14v, resulting in 0v across the motor. inputs more positive than 5v result in motor current ?ow from left to right (see figure 1). inputs less positive than 5v drive the motor in the opposite direction. the ampli?ers are especially well-suited for this application. the extended common mode range allows command inputs as low as 0v. its superior output swing abilities let it drive within 2v of supply at an output current of 2a. this means that a command input that ranges from 0.714v to 9.286v will drive a 24v motor from full scale ccw to full scale cw at up to 2a. a single power op amp with an output swing capability of vs C6 would require 30v supplies and would be required to swing 48v p-p at twice the speed to deliver an equivalent drive. external connections (top views) PA74 pa76 figure 1: bidirectional speed control from a single supply. 8-pin to-3 package style ce ?? ? ??? ?? ? ??? ?????? ??????? ??????? ??????? ??????? ???? ??????? ???? ???
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 2 absolute maximum ratings specifications PA74/76 ? PA74a/pa76a absolute maximum ratings supply voltage, total 5v to 40v output current soa power dissipation, internal (per ampli?er) 36w power dissipation, internal (both ampli?ers) 60w input voltage, differential v s input voltage, common mode +v s , -v s C0.5v junction temperature, max 1 150c temperature, pin solderC10 sec max 300c temperature range, storage C65c to 150c operating temperature range, case C55c to 125c specifications PA74/76 PA74a/pa76a parameter test conditions 2 min typ max min typ max units input offset voltage, initial 1.5 10 .5 7 mv offset voltage, vs. temperature full temperature range 20 10 v/c bias current, initial 100 500 * 250 na common mode range full temperature range Cv s +v s C1.3 * * v common mode rejection, dc full temperature range 60 70 * * db power supply rejection full temperature range 60 90 * * db channel separation i out = 1a, f = 1khz 50 70 * * db input noise voltage r s = 100?, f = 1 to 100khz gain open loop gain full temperature range 89 100 * * * db gain bandwidth product a v = 40db 0.9 1.4 * * mhz power bandwidth v o(p-p) = 28v 13.6 * khz output current, peak 2.5 3 a slew rate 0.5 1.4 * * v/s voltage swing full temp. range, i o = 100ma |v s | C1.1 |v s | C0.9 * * v voltage swing full temp. range, i o = 1a |v s | C2.0 |v s | C1.7 * * v voltage swing i o = 2.5a (PA74, 76) |v s | C3.5 |v s | C2.9 * * v voltage swing i o = 3.0a (PA74a, pa76a) |v s | C4.0 |v s | C3.3 v power supply voltage, vss 3 30 40 * * * v current, quiescent, total 18 40 * * ma thermal resistance, junction to case dc, single ampli?er 3.2 3.5 * * c/w dc, both ampli?ers 4 1.9 2.1 * * c/w ac, single ampli?er 2.4 2.6 * * c/w ac, both ampli?ers 4 1.4 1.6 * * c/w resistance, junction to air 30 * * c/w temperature range, case meets full range speci?cations C25 85 C25 85 c notes: * the speci?cation of PA74a/pa76a is identical to the speci? cation for PA74/pa76 in applicable column to the left. 1. long term operation at the maximum junction temperature will result in reduced product life. derate internal power dissipation to achieve high mttf. 2. unless otherwise noted, the following conditions apply: vs = 15v, tc = 25c. 3. +vs and Cvs denote the positive and negative supply rail respectively. vss denotes the total rail-to-rail supply voltage. 4. rating applies when power dissipation is equal in the two ampli? ers. the internal substrate contains beryllia (beo). do not break the seal. if accidentally broken, do not crush, machine, or subject to temperatures in excess of 850c to avoid generating toxic fumes. caution
apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 3 typical performance graphs PA74/76 ? PA74a/pa76a ??? ??? ??? ?? ?? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??????????????????????????????? ? ???? ??????????????????? ? ????? ???????????????????????????? ???????????????????? ???????????????????????????? ????????????????? ??????????????????????????????? ? ???? ????????????????? ? ???? ?? ? ?? ?? ? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???????????????????? ????????????????? ? ???? ??????????????????????????? ???? ???? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ?????????????? ??????????? ????????????????? ? ???? ??? ???? ???? ???? ??? ??? ??? ? ??? ?? ?? ? ? ?? ??? ?? ? ??????? ? ? ????? ? ?? ??????? ?? ? ??????? ? ? ?????? ? ?? ??????? ?????????????? ??????????? ????????????????? ? ???? ?? ?? ?? ?? ?? ?? ?? ? ??? ?? ?? ? ? ?? ??? ?? ? ??????? ? ? ????? ? ?? ??????? ?? ? ??????? ? ? ?????? ? ?? ???????? ? ?? ?? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ?????????????????????????? ? ???? ????????????????? ? ? ????????????????? ?? ??? ??? ??? ??? ??? ?? ??? ???? ?? ??? ???????????? ??????????????????? ????????????????? ?? ?? ?? ? ??? ??? ?? ??? ???? ?? ??? ???????????? ?????????????????????????? ?? ? ?? ???????????????????????????? ?? ???? ??? ?? ?? ? ??? ?? ? ? ? ?????????????????
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 4 operating considerations PA74/76 ? PA74a/pa76a this data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. all speci?cations are subject to change without notice. PA74C76u rev c november 2004 ? 2004 apex microtechnology corp. general please read application note 1 "general operating consider - ations" which covers stability, supplies, heatsinking, mounting, soa interpretation, and speci?cation interpretation. visit www. apexmicrotech.com for design tools that help automate tasks such as calculations for stability, internal power dissipation, heatsink selection; apex's complete application notes library; technical seminar workbook; and evaluation kits. stability considerations all monolithic power op amps use output stage topologies that present special stability problems. this is primarily due to non-complementary (both devices are npn) output stages with a mismatch in gain and phase response for different polarities of output current. it is dif?cult for the opamp manufacturer to optimize compensation for all operating conditions. safe operating area (soa) the soa curves combine the effect of all limits for this power op amp. for a given application, the direction and magnitude of the output current should be calculated or measured and checked against the soa curves. this is simple for resistive loads but more complex for reactive and emf generating loads. thermal considerations thermal grease or an apex tw03 thermal washer, rcs = .1 to .2c/w, is the only recommended interface for the PA74/76. internal power dissipation increases directly with frequency therefore it is critical to suf?ciently heat sink the PA74 and pa76. even unloaded the PA74 and pa76 can dissipate up to 3 watts while running at higher frequencies. ??? ????????????????????? ????????????? ?????? ??? ??? ?? ??? ??? ?? ???????????????????????????????????????? ? ???? ? ???? ?????????????????????? ? ?????? ? ????? ????? ? ??????? ????? ? ??????? parallel configuration considerations losses the PA74 and pa76 utilize a parallel con?guration to achieve the desired current output requirements. the paral - lel con?guration inherently creates internal losses due to circulating currents. the circulating currents generate power losses through the current sharing resistors when delivering current to the load. supply current the parallel con?guration used in the PA74 and pa76 also generates supply currents while high voltage sign waves are seen at the output. listed below are the supply currents expected while running at a particular frequency and when vo 15vpp, note that the outputs are not loaded. frequency supply current 100hz 18ma 1khz 20ma 5khz 32ma 10khz 50ma 15khz 75ma saturation operation the parallel con?guration used in the PA74 and pa76 is sensitive to operation in the saturation region. the PA74 and pa76 may exhibit large peak currents; this is mainly due to thermal protection limitations. ? ?? ?? ?? ?? ?? ?? ?? ?????????????? ? ?? ?? ?? ??? ??? ????????????????????? ???????????????????? ??????????????????? ? ????? ?????????????????????????????????
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