apex microtechnology corporation ?telephone (520) 690-8600 ?fax (520) 888-3329 ?orders (520) 690-8601 ?email prodlit@apexmicrotech.com features ?wide supply range ? 10 to 45v ?high output current ? 10a peak ?low cost ?class ??output stage ?low quiescent current ?3ma applications ?programmable power supply ?motor/syncro driver ?valve and actuator control ?dc or ac power regulator ?fixed frequency power oscillator description the pa61 and PA61A are high output current operational amplifiers designed to drive resistive, inductive and capacitive loads. their complementary emitter follower output stage is the simple class c type and optimized for low frequency applications where crossover distortion is not critical. these amplifiers are not recommended for audio, transducer or deflection coil drive circuits above 1khz or when distortion is critical. the safe operating area (soa) is fully specified and can be observed for all operating conditions by selection of user programmable current limiting resistors. both amplifiers are internally compensated for all gain settings. for continu- ous operation under load, mounting on a heatsink of proper rating is recommended. this hybrid circuit utilizes thick film conductors, ceramic capacitors, and semiconductor chips to maximize reliability, minimize size, and give top performance. ultrasonically bonded aluminum wires provide reliable interconnections at all operating temperatures. the 8-pin to-3 package is electri- cally isolated and hermetically sealed. the use of compres- sible thermal washers and/or improper mounting torque voids the product warranty. please see ?eneral operating consid- erations? equivalent schematic top view 1 2 3 4 5 6 7 8 c l v s +in in +v s out n.c. c l+ r cl+ r cl output +42v 42v r f1 pa61 r cl+ r cl r f2 r w rtn sense lo r w 10v sense hi load dac r in1 r in2 out figure 1. programmable power supply with remote sensing 2 8 1 3 6 4 5 a1 q3 q4 c1 q1a q1b q6b q6a typical application due to its high current drive capability, pa61 applications often utilize remote sensing to compensate ir drops in the wiring. the importance of remote sensing increases as accu- racy requirements, output currents, and distance between amplifier and load go up. the circuit above shows wire resistance from the pa61 to the load and back to the local ground via the power return line. without remote sensing, a 7.5a load current across only 0.05 ohm in each line would produce a 0.75v error at the load. with the addition of the second ratio matched r f /r in pair and two low current sense wires, ir drops in the power return line become common mode voltages for which the op amp has a very high rejection ratio. voltage drops in the output and power return wires are inside the feedback loop. therefore, as long as the power op amp has the voltage drive capability to overcome the ir losses, accuracy remains the same. applica- tion note 7 presents a general discussion of pps circuits. external connections http://www.apexmicrotech.com (800) 546-apex (800) 546-2739 microtechnology power operational amplifiers pa61 ?PA61A
apex microtechnology corporation 5980 north shannon road tucson, arizona 85741 usa applications hotline: 1 (800) 546-2739 parameter test conditions 2 min typ max min typ max units input offset voltage, initial t c = 25 c 2 6 1 3mv offset voltage, vs. temperature specified temperature range 10 65 * 40 v/ c offset voltage, vs. supply t c = 25 c 30 200 * * v/v offset voltage, vs. power t c = 25 c 20 * v/w bias current, initial t c = 25 c 1230 1020na bias current, vs. temperature specified temperature range 50 500 * * pa/ c bias current, vs. supply t c = 25 c 10 * pa/v offset current, initial t c = 25 c 12 30 5 10 na offset current, vs. temperature specified temperature range 50 * pa/ c input impedance, dc t c = 25 c 200 * m ? input capacitance t c = 25 c3*pf common mode voltage range 3 specified temperature range v s 5 v s 3** v common mode rejection, dc 3 specified temperature range 74 100 * * db gain open loop gain at 10hz full temp. range, full load 96 108 * * db gain bandwidth product at 1mhz t c = 25 c, full load 1 * mhz power bandwidth t c = 25 c, i o = 8a, v o = 40v pp 10 16 * * khz phase margin full temperature range 45 * output voltage swing 3 t c = 25 c, i o = 10a v s 7 v s 5 v s 6* v voltage swing 3 full temp. range, i o = 4a v s 6 v s 4** v voltage swing 3 full temp. range, i o = 68ma v s 5* v current t c = 25 c 10 * a settling time to .1% t c = 25 c, 2v step 2 * s slew rate t c = 25 c, r l = 6 ? 1.0 2.8 * * v/ s capacitive load, unit gain full temperature range 1.5 * nf capacitive load, gain>4 full temperature range soa * power supply voltage full temperature range 10 32 45 * * * v current, quiescent t c = 25 c310**ma thermal resistance, ac, junction to case 4 f > 60hz 1.0 1.2 * * c/w resistance, dc, junction to case f < 60hz 1.5 1.8 * * c/w resistance, junction to air 30 * c/w temperature range, case meets full range specification 25 25 +85 * * * c absolute maximum ratings specifications specifications absolute maximum ratings supply voltage, +v s to v s 90v output current, within soa 10a power dissipation, internal 97w input voltage, differential v s 3v input voltage, common mode v s temperature, pin solder-10s 300 c temperature, junction 1 200 c temperature range, storage 65 to +150 c operating temperature range, case 55 to +125 c PA61A pa61 pa61 PA61A notes: * the specification of PA61A is identical to the specification for pa61 in applicable column to the left. 1. long term operation at the maximum junction temperature will result in reduced product life. derate internal power dissipatio n to achieve high mttf. 2. the power supply voltage for all specifications is the typ rating unless noted as a test condition. 3. +v s and v s denote the positive and negative supply rail respectively. total v s is measured from +v s to v s . 4. rating applies if the output current alternates between both output transistors at a rate faster than 60hz. 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 850 c 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 typical performance graphs pa61 PA61A 0 25 50 75 100 125 150 temperature, t ( c) 0 20 60 100 power derating internal power dissipation, p (w) 50 0 100 .7 1.9 2.2 bias current 1.3 .4 10 100 10k .1m frequency, f (hz) input noise voltage, v (nv/ hz) 1 100 10m frequency, f (hz) 20 0 60 120 small signal response open loop gain, a ol (db) 20 40 80 100 1 100 .1m 10m 210 150 60 0 phase response 90 30 frequency, f (hz) output voltage, v (v ) o frequency, f (hz) harmonic distortion distortion, (%) 40 total supply voltage, v s (v) .4 .6 1.6 quiescent current normalized quiescent current, i q (x) .8 1.4 1 10k frequency, f (hz) 0 common mode rejection common mode rejection, cmr(db) 40 80 120 .1m 10 100 25 50 100 case temperature, t ( c) 0 6 current limit current limit, i (a) lim 5 c input noise 1k 10 20 30 n 1k 25 25 50 75 1.6 40 power response pp 50 60 70 80 90 1.2 025 75 2 3 10 1k 10k .1m 1m 80 10 10k 1m frequency, f (hz) phase, ( ) normalized bias current, i b (x) 1 4 1k 1m 20 60 100 1.0 125 1.0 125 7 case temperature, t ( c) c 180 120 40 50 70 100 2.5 c 30 20 0 output current, i o (a) output voltage swing voltage drop from supply (v) 3.0 246810 3.5 4.0 4.5 5.0 5.5 2.5 0 time, t (s) pulse response output voltage, v (v) 8 2 4 6 8 10 12 6 4 2 0 2 4 6 8 o 14 r c l = .12 ? r cl = 0.3 ? t c = 25 to 85 c t c = 25 c t = t c 21 30 41 58 15 80 11 10k .1m 20k 30k 50k 70k 8 r l = 8 ? r l = 3 ? v s = 40v r l = 5 ? a v = +1 1 3 10 .3 .1 30 300 1k 10k 100 30k .03 .01 3k v s = 36 r l = 4 a v = 10 ? p o = 5w p o = .1w p o = 50w t c = 55 c t c = 25 c t c = 125 c
apex microtechnology corporation 5980 north shannon road tucson, arizona 85741 usa applications hotline: 1 (800) 546-2739 operating considerations pa61 PA61A general please read application note 1 "general operating consid- erations" which covers stability, supplies, heat sinking, mount- ing, current limit, soa interpretation, and specification inter- pretation. visit www.apexmicrotech.com for design tools that help automate tasks such as calculations for stability, internal power dissipation, current limit and heat sink selection. the "application notes" and "technical seminar" sections contain a wealth of information on specific types of applications. package outlines, heat sinks, mounting hardware and other accessories are located in the "packages and accessories" section. evaluation kits are available for most apex product models, consult the "evaluation kit" section for details. for the most current version of all apex product data sheets, visit www.apexmicrotech.com. safe operating area (soa) the output stage of most power amplifiers has 3 distinct limitations: 1. the current handling capability of the transistor geometry and the wire bonds. 2. the second breakdown effect which occurs whenever the simultaneous collector current and collector-emitter voltage exceeds specified limits. 3. the junction temperature of the output transistors. 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. the following guidelines may save extensive analytical efforts. 1. under transient conditions, capacitive and dynamic* induc- tive loads up to the following maximum are safe: capacitive load inductive load v s i lim = 5a i lim = 10a i lim = 5a i lim = 10a 45v 200 f 150 f 8mh 2.8mh 40v 400 f 200 f 11mh 4.3mh 35v 800 f 400 f 20mh 5.0mh 30v 1600 f 800 f 35mh 6.2mh 25v 5.0mf 2.5mf 50mh 15mh 20v 10mf 5.0mf 400mh 20mh 15v 20mf 10mf ** 100mh * if the inductive load is driven near steady state conditions, allowing the output voltage to drop more than 8v below the supply rail with i lim = 10a or 15v below the supply rail with i lim = 5a while the amplifier is current limiting, the inductor should be capacitively coupled or the current limit must be lowered to meet soa criteria. ** second breakdown effect imposes no limitation but thermal limitations must still be observed. 2. the amplifier can handle any emf generating or reactive load and short circuits to the supply rail or shorts to common if the current limits are set as follows at t c =85 c. short to v s short to v s c, l, or emf load common 45v 0.1a 1.3a 40v 0.2a 1.5a 35v 0.3a 1.6a 30v 0.5a 2.0a 25v 1.2a 2.4a 20v 1.5a 3.0a 15v 2.0a 4.0a these simplified limits may be exceeded with further analy- sis using the operating conditions for a specific application. 3. the output stage is protected against transient flyback. however, for protection against sustained, high energy flyback, external fast-recovery diodes should be used. this data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible i naccuracies or omissions. all specifications are subject to change without notice. pa61u rev. h january 2001 ? 2001 apex microtechnology corp. tc=125 c tc=85c steady state t=5 ms t=1 m s t=0.5ms 10 20 30 supply to output differential voltage v s v o (v) safe operating area (soa) input current from +v s or v s (a) 40 50 60 70 90 80 .1 .2 .3 .4 .6 .8 1.0 2.0 3.0 4.0 6.0 8.0 10 1.5 tc=25 c 25 15
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