apex microtechnology corporation ?telephone (520) 690-8600 ?fax (520) 888-3329 ?orders (520) 690-8601 ?email prodlit@apexmicrotech.com features high voltage ?400v ( 200v) low quiescent current ?10ma high output current 4a programmable current limit applications piezoelectric positioning high voltage instrumentation electrostatic transducers programmable power supplies up to 390v description the PA92 is a high voltage, low quiescent current mosfet operational amplifier designed as a low cost solution for driving continuous output currents up to 4a and pulse currents up to 7a. the safe operating area (soa) has no second breakdown limitations and can be observed for all type loads by choosing an appropriate current limiting resistor. the mosfet output stage is biased ab for linear operation. external compensation provides flexibility in choosing bandwidth and slew rate for the application. apex? power sip package uses a minimum of board space allowing for high density circuit boards. equivalent schematic q1 q2 r1 r2 c1 r3 q3 cc1 12 11 1 4 5 9 6 10 2 7 8 cc2 3 q6 q5 r5 r8 r9 q15 r11 r12 q16 q12 q8 r4 r7 q4 ilim out q14 r10 q13 q11 +v s in +in v s i q r6 low power, piezoelectric positioning typical application piezo positioning may be applied to the focusing of seg- mented mirror systems. the composite mirror may be com- posed of hundreds of elements, each requiring focusing under computer control. in such complex systems the PA92 reduces the costs of power supplies and cooling with its advantages of low cost and low quiescent power consumption while increas- ing circuit density with the sip package. phase compensation f r PA92 in r 1 2 6 7,8 9,10 11,12 piezo drive s v s +v out v computer focus command voltage cl r http://www.apexmicrotech.com (800) 546-apex (800) 546-2739 microtechnology high voltage power operational amplifier PA92 gain c c *r c 1 150pf 100 ? 100 ? 0 ? 0 ? 100pf 47pf 10pf 2 3 12 *c c never to be < 10pf. c c to be rated for the full supply voltage +v to vs. use ceramic npo (cog) type. 1 234 56 78 910 in +in r cl +v s v s to load and feedback 11 12 r c c c * * (see text.) * bypassing required. i q external connections package: sip03 patented
apex microtechnology corporation 5980 north shannon road tucson, arizona 85741 usa applications hotline: 1 (800) 546-2739 absolute maximum ratings specifications absolute maximum ratings supply voltage, +v s to v s 400v output current, source, sink, peak 7a, within soa power dissipation, continuous @ t c = 25 c 80w input voltage, differential 20v input voltage, common mode v s temperature, pin solder - 10s max 220 c temperature, junction 2 150 c temperature, storage 65 to +150 c operating temperature range, case 55 to +125 c PA92 specifications parameter test conditions 1 min typ max units input offset voltage, initial 210mv offset voltage, vs. temperature full temperature range 15 50 v/ c offset voltage, vs. supply 10 25 v/v offset voltage, vs. time 75 v/ kh bias current, initial 200 2000 pa bias current, vs. supply 4 pa/v offset current, initial 50 500 pa input impedance, dc 10 11 ? input capacitance 4pf common mode voltage range 3 v s 15 v common mode rejection, dc v cm = 90v 80 98 db noise 100khz bw, r s = 1k ? , c c = 10pf 1 vrms gain open loop, @ 15hz r l = 2k ? , c c = 10pf 94 111 db gain bandwidth product at 1mhz r l = 2k ? , c c = 10pf 18 mhz power bandwidth r l = 2k ? , c c = 10pf 30 khz phase margin full temperature range 60 output voltage swing 3 i o = 4a v s 12 v s 10 v current, continuous 4 a slew rate, a v = 100 c c = 10pf 50 v/ s capacitive load, a v = +1 full temperature range 1 nf settling time to .1% c c = 10pf, 2v step 1 s resistance, no load 10 ? power supply voltage 5 see note 5 50 150 200 v current, quiescent, 10 14 ma thermal resistance, ac, junction to case 4 full temperature range, f > 60hz 1 c/w resistance, dc, junction to case full temperature range, f < 60hz 1.5 c/w resistance, junction to air full temperature range 30 c/w temperature range, case meets full range specifications 25 +85 c notes: 1. unless otherwise noted: t c = 25 c, dc input specifications are value given. power supply voltage is typical rating. r c = 100 c c = 150pf. 2. long term operation at the maximum junction temperature will result in reduced product life. derate internal power dissipatio n to achieve high mttf. 3. +v s and v s denote the positive and negative power supply rail respectively. 4. rating applies if the output current alternates between both output transistors at a rate faster than 60hz. 5. derate max supply rating .625 v/ c below 25 c case. no derating needed above 25 c case. caution the PA92 is constructed from mosfet transistors. esd handling procedures must be observed.
apex microtechnology corporation telephone (520) 690-8600 fax (520) 888-3329 orders (520) 690-8601 email prodlit@apexmicrotech.com typical performance graphs PA92 0 25 50 75 100 125 case temperature, t ( c) 0 40 60 power derating internal power dissipation, p(w) 100k frequency f (hz) 135 90 phase response phase, ( ) 10 100 10k 100k frequency, f (hz) input noise voltage, v (nv hz) 100k frequency, f (hz) 10 0 30 small signal response open loop gain, a (db) 10 20 40 50 0 34 output current, i (a) 7.5 8.5 output voltage swing 7.0 8.0 1m frequency, f (hz) 10 output voltage, v (v ) o 100 400 0.0 0.4 0.6 1.0 1.2 resistor value, r ( ) 0 1 4 current limit current limit, i (a) lim 2 3 10 60 ext. compensation capacitor, c (pf) 1 slew rate slew rate, (v/ s) 4 3 2 60 100 200 300 frequency, f (hz) harmonic distortion distortion, (%) .01 .1 10k 100 1k 0 50 100 case temperature, tc ( c) 1.2 normalized quies. current normalized quiescent current, i (x) q 1.0 cl 0.2 0.8 input noise voltage 1k 2 7 10 20 5 3 15 n o 1 voltage drop from supply, v v (v) so 225 20 80 power response pp 75 c .001 1m 10m 270 180 c 125 1.4 1.6 2 6.5 40 20 10 8 6 30 30 1k 10k 100k 1m 10m c = 150pf c c = 100pf c c = 47pf c c = 10pf c c c = 150 pf c c = 100 pf c c = 47 pf c c = 10 pf c c = 150 pf c c = 100 pf c c = 47 pf c c = 10 pf p o = 1w p o = 20w p o = 62w ?
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. PA92u rev. c may 2000 ? 2000 apex microtechnology corp. operating considerations PA92 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; heat sink selection; apex s complete application notes library; technical seminar work- book; and evaluation kits. current limit for proper operation, the current limit resistor (r cl ) must be connected as shown in the external connection diagram. for optimum reliability the resistor value should be set as high as possible. the value is calculated as follows; with the maximum practical value of 16 ohms. .65 r cl = i lim safe operating area (soa) the mosfet output stage of this power operational ampli- fier has two distinct limitations: 1. the current handling capability of the mosfet geometry and the wire bonds. 2. the junction temperature of the output mosfets. note: the output stage is protected against transient flyback. however, for protection against sustained, high energy flyback, external fast-recovery diodes should be used. safe operating curves the safe operating area curves define the maximum addi- tional internal power dissipation the amplifier can tolerate when it produces the necessary output to drive an external load. input protection although the PA92 can withstand differential voltages up to 20v, additional external protection is recommended. low leakage, low capacitance jfets connected as diodes are recommended (e.g. 2n4416, q1-q4 in figure 2). the differen- tial input voltage will be clamped to 1.4v. this is sufficient overdrive to produce maximum power bandwidth. power supply protection unidirectional zener diode transient suppressors are recom- mended as protection on the supply pins. see figure 2. the zeners clamp transients to voltages within the power supply rating and also clamp power supply reversals to ground. whether the zeners are used or not, the system power supply should be evaluated for transient performance including power- on overshoot and power-off polarity reversals as well as line regulation. conditions which can cause open circuits or polarity rever- sals on either power supply rail should be avoided or protected against. reversals or opens on the negative supply rail is known to induce input stage failure. unidirectional transzorbs prevent this, and it is desirable that they be both electrically and physically as close to the amplifier as possible. stability the PA92 is externally compensated and performance can be tailored to the application. use the graphs of small signal response and power response as a guide. the compensation capacitor c c must be rated at 500v working voltage. an npo capacitor is recommended. the compensation network c c r c must be mounted closely to the amplifier pins 4 and 5 to avoid spurious oscillation. quiescent current reduction when pin 3 (i q ) is shorted to pin 5 (cc2) the ab biasing of the output stage is disabled. this lowers quiescent power but also raises distortion since the output stage is then class c biased. the output stage bias current is nominally set at 1ma. pin 3 may be left open if not used. supply to output differential, v s v o (v) 10 20 30 40 80 100 200 300 500 output current from +v s or v s , (a) .04 .2 .1 .08 .06 .3 .8 .6 .4 1 2 4 8 6 t c = 125 c t c = 85 c 100ms 60 200ms dc, t c = 25 c +v s in +in z1 z2 11, 12 7, 8 1 2 6 PA92 q1 q2 v s q3 q4 figure 2. overvoltage protection
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