apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 1 features ? monolithic mos technology ? low cost ? high voltage operation350v ? low quiescent current typ.2.2ma ? no second breakdown ? high output current120ma peak ? available in die formcpa241 applications ? piezo electric positioning ? electrostatic transducer & deflection ? deformable mirror focusing ? biochemistry stimulators ? computer to vacuum tube interface description the pa241 is a high voltage monolithic mosfet operational ampli?er which achieves performance features previously found only in hybrid designs while increasing reliability. inputs are protected from excessive common mode and differential mode voltages. the safe operating area (soa) has no second breakdown limitation and can be observed with all type loads by choosing an appropriate current limiting resistor. external compensation provides the user ?exibility in choosing optimum gain and bandwidth for the application. the pa241ce is packaged in a hermetically sealed 8-pin to-3 package. the metal case of the pa241ce is isolated in excess of full supply voltage. the pa241df is packaged in a 24 pin psop (jedec mo- 166) package. the metal heat slug of the pa241df is isolated in excess of full supply voltage. the pa241dw is packaged in apexs hermetic ceramic sip package. the alumina ceramic isolates the die in excess of full supply voltage. equivalent schematic ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ????????????????????????????????????????? ????? ??? ????? ?????????? ??? ?? ??? ?? ? ? ?? ???? ???? ???? ???? ? ?? ? ?? ??? ??? ???? ???? ?? ????? ?? ????? low cost 660v p-p piezo drive two pa241 ampli?ers operated as a bridge driver for a piezo transducer provides a low cost 660 volt total drive capability. the r n c n network serves to raise the apparent gain of a2 at high frequencies. if r n is set equal to r the ampli?ers can be compensated identically and will have matching bandwidths. external connections r cl 1 4 5 6 7 3 2 8 9 10 c c +in -in nc nc -v s +v s i lim c c 2 c c 1 out pa241dw r cl top view 1 2 3 4 5 6 7 8 out i lim Cv s +v s c c 1 Cin +in c c 2 c c note: pa241ce recommended mounting torque is 4-7 in?lbs (.45 -.79 n?m) caution: the use of compressible, thermally conductive insulators may void warranty. pa241ce 8-pin to-3 24-pin psop 10-pin sip package style ce package style df package style dw i lim out -in +in +v s -v s c c 2 c c 1 typical application ref: application note 20: "bridge mode operation of power ampli?ers" c c r cl nc nc nc nc -in nc +in nc nc nc nc -vs nc nc nc out nc comp nc comp nc ilim nc +vs 24 1 + - pa241df for cc values, see graph on page 4. note: cc must be rated for full supply voltage.
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 2 absolute maximum ratings specifications pa241 absolute maximum ratings pa241ce pa241df pa241cea pa241dfa supply voltage, +v s to Cv s 350v 350v output current, continuous within soa 60 ma 60 ma output current, peak 120 ma 120 ma power dissipation, continuous @ t c = 25c 12w 12w input voltage, differential 16 v 16 v input voltage, common mode v s v s temperature, pin solder C 10 sec 300c 220c temperature, junction 2 150c 150c temperature, storage C65 to +150c C65 to +150c temperature range, powered (case) C40 to +125c C40 to +125c caution the pa241 is constructed from mosfet transistors. esd handling procedures must be observed. pa241ce, pa241df pa241cea parameter test conditions 1 min typ max min typ max units input offset voltage, initial 25 40 15 30 mv offset voltage, vs. temperature 3 full temperature range 100 500 * * v/c offset voltage, vs supply 3 * v/v offset voltage, vs time 70 130 * * v/kh bias current, initial 6 5/50 50/200 * * pa bias current, vs supply 0.2/2 * pa/v offset current, initial 6 2.5/50 50/200 * * pa input impedance, dc 10 11 * input capacitance 6 * pf common mode, voltage range +v s C14 * v common mode, voltage range -v s +12 * v common mode rejection, dc v cm = 90v dc 84 94 * * db noise, broad band 10khz bw, r s = 1k 50 * v rms noise, low frequency 1-10 hz 125 * v p-p gain open loop at 15hz r l = 5k 90 96 * * db bandwidth, gain bandwidth product 3 * mhz power bandwidth 280v p-p 30 * khz output voltage swing i o = 40ma v s C12 v s C10 v s C10 v s C8.5 v current, peak 4 120 * ma current, continuous 60 * ma settling time to .1% 10v step, a v = C10 2 * s slew rate c c = 3.3pf 30 * v/s resistance 5 , 1ma r cl = 0 150 * ? resistance 5 , 40 ma r cl = 0 5 * ? power supply voltage 50 150 175 * * * v current, quiescent 2.2 2.5 * 2.3 ma thermal pa241ce resis tance, ac junction to case f > 6 0hz 5.4 6.5 * * c/w pa241df resis tance, ac junction to case f > 6 0hz 6 7 * * c/w pa241ce resis tance, dc junction to case f < 6 0hz 9 10.4 * * c/w pa241df resis tance, dc junction to case f < 6 0hz 9 11 * * c/w pa241ce resistance, junction to air full temperature range 30 * c/w pa241df resistance, junction to air 7 full temperature range 25 * c/w temperature range, case meets full range spec's C25 +85 * * c specifications notes: * "a" speci?cation is the same as the non "a" speci?cation. 1. unless otherwise noted t c = 25c, c c = 6.8pf. dc input speci?cations are value given. power supply voltage is typical rating. 2. long term operation at the maximum junction temperature will result in reduced product life. derate internal power dissipation to achieve high mttf. for guidance, refer to heatsink data sheet. 3. sample tested by wafer to 95%. 4. guaranteed but not tested. 5. the selected value of r cl must be added to the values given for total output resistance. 6. speci? cations separated by / indicate values for the pa241ce and pa241df respectively. 7. rating applies with solder connection of heatslug to a minimum 1 square inch foil area of the printed circuit board.
apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 3 absolute maximum ratings specifications pa241 caution the pa241 is constructed from mosfet transistors. esd handling procedures must be observed. absolute maximum ratings pa241dw PA241DWA supply voltage, +v s to Cv s 350v output current, continuous within soa 60 ma output current, peak 120 ma power dissipation, continuous @ t c = 25c 9w input voltage, differential 16 v input voltage, common mode v s temperature, pin solder C 10 sec 220c temperature, junction 2 150c temperature, storage C65 to +150c temperature range, powered (case) C40 to +125c pa241dw PA241DWA parameter test conditions 1 min typ max min typ max units input offset voltage, initial 25 40 15 30 mv offset voltage, vs. temperature 3 full temperature range 100 500 * * v/c offset voltage, vs supply 3 * v/v offset voltage, vs time 70 130 * v/kh bias current, initial 100 2000 * * pa bias current, vs supply 15 50 * * pa/v offset current, initial 100 400 * * pa input impedance, dc 10 11 * input capacitance 6 * pf common mode, voltage range +v s C14 * v common mode, voltage range -v s +12 * v common mode rejection, dc v cm = 90v dc 84 94 * * db noise, broad band 10khz bw, r s = 1k 50 * v rms noise, low frequency 1-10 hz 125 * v p-p gain open loop at 15hz r l = 5k 90 96 * * db bandwidth, gain bandwidth product 3 * mhz power bandwidth 280v p-p 30 * khz output voltage swing i o = 40ma v s C12 v s C10 v s C10 v s C8.5 v current, peak 4 120 * ma current, continuous 60 * ma settling time to .1% 10v step, a v = C10 2 * s slew rate c c = 3.3pf 30 * v/s resistance 5 , 1ma r cl = 0 150 * ? resistance 5 , 40 ma r cl = 0 5 * ? power supply voltage 50 150 175 * * * v current, quiescent 2.2 2.5 * 2.3 ma thermal pa241dw resis tance, ac junction to case f > 6 0hz 7 10 * * c/w pa241dw resis tance, dc junction to case f < 6 0hz 12 14 * * c/w pa241dw resistance, junction to air full temperature range 55 * c/w temperature range, case meets full range spec's C25 +85 * * c specifications notes: * "a" speci?cation is the same as the non "a" speci?cation. 1. unless otherwise noted t c = 25c, c c = 6.8pf. dc input speci?cations are value given. power supply voltage is typical rating. 2. long term operation at the maximum junction temperature will result in reduced product life. derate internal power dissipation to achieve high mttf. for guidance, refer to heatsink data sheet. 3. sample tested by wafer to 95%. 4. guaranteed but not tested. 5. the selected value of r cl must be added to the values given for total output resistance.
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 4 typical performance graphs pa241 ?? ?? ?? ?? ??? ? ? ?? ?? ? ????????????????? ? ????? ????????????? ? ????? ???????????????????? ??? ? ? ????? ??????? ? ????? ??????? ? ????? ??????? ? ????? ??????? ????????????????? ?????????????????????? ???????????????????????????????? ?? ??? ?? ??? ???? ?? ?? ?? ?? ?? ?? ??? ???????? ???????? ??? ?? ????????????????? ? ?? ??? ????????????????????? ??????????????????????????????? ?? ?? ??? ?? ??? ???? ?? ????????????????? ????????????????????????? ???????????????????????????????? ??? ??? ?? ?? ??? ??? ??? ?? ?? ??? ??? ??? ??? ??? ??? ? ? ???????? ? ? ??????? ? ? ??????? ??????????????????????????? ? ????? ???????????????? ????????? ?? ?? ?? ?? ?? ? ? ?? ?? ?? ?? ?? ??? ??? ????????????????? ????? ??????????????????? ??????????????? ?? ?? ???? ??? ???? ? ???? ??? ???? ??? ????? ??? ? ? ????? ? ? ??????? ? ? ????? ????????????????? ?????????????????? ??? ?????? ???? ?? ??? ?? ??? ???? ?????????????? ????? ????? ???? ???? ???? ?? ??? ???? ??? ???? ???? ???? ???? ???? ???? ???? ?????????????? ????????????????? ???????????? ???? ???? ????? ????? ???? ???? ??? ??? ?? ??? ?? ???? ???? ????? ????? ??? ?? ?? ?? ?? ? ??? ????????????????????? ?????????????????????? ????????????????? ??? ?? ???? ? ? ??????? ? ? ??????? ? ? ??????? ? ? ???????? ??? ?? ? ??? ???????????????? ??? ?? ? ???? ????????????????????? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ? ????? ???????????????? ? ?? ???? ??? ??? ??? ? ?? ?? ?? ?? ??? ??? ????????????????? ? ?? ? ? ?? ? ? ?? ?? ?? ??? ??? ??????????????????? ? ? ? ?????????????? ???????????????????????????????? ?? ? ?? ??????? ??????? ????? ? ????? ? ????? ? ????? ? ???????
apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 5 operating considerations pa241 general please read application note 1 "general operating consid - erations" which covers stability, power supplies, heat sinking, mounting, current limit, 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, current limit, heat sink selection, apex's complete application notes library, technical seminar workbook and evaluation kits. phase compensation open loop gain and phase shift both increase with increas - ing temperature. the phase compensation typical graph shows closed loop gain and phase compensation capacitor value relationships for four case temperatures. the curves are based on achieving a phase margin of 50. calculate the highest case temperature for the application (maximum ambient temperature and highest internal power dissipation) before choosing the compensation. keep in mind that when working with small values of compensation, parasitics may play a large role in performance of the ?nished circuit. the compensation capacitor must be rated for at least the total voltage applied to the ampli?er and should be a temperature stable type such as npo or cog. other stability concerns there are two important concepts about closed loop gain when choosing compensation. they stem from the fact that while "gain" is the most commonly used term, (the feedback factor) is really what counts when designing for stability. 1. gain must be calculated as a non-inverting circuit (equal input and feedback resistors can provide a signal gain of -1, but for calculating offset errors, noise, and stability, this is a gain of 2). 2. including a feedback capacitor changes the feedback factor or gain of the circuit. consider rin=4.7k, rf=47k for a gain of 11. compensation of 4.7 to 6.8pf would be reasonable. adding 33pf parallel to the 47k rolls off the circuit at 103khz, and at 2mhz has reduced gain from 11 to roughly 1.5 and the circuit is likely to oscillate. as a general rule the dc summing junction impedance (parallel combination of the feedback resistor and all input resistors) should be limited to 5k ohms or less. the ampli?er input capacitance of about 6pf, plus capacitance of connecting traces or wires and (if used) a socket will cause undesirable circuit performance and even oscillation if these resistances are too high. in circuits requiring high resistances, measure or estimate the total sum point capacitance, multiply by rin/rf, and parallel rf with this value. capacitors included for this purpose are usually in the single digit pf range. this technique results in equal feedback factor calculations for ac and dc cases. it does not produce a roll off, but merely keeps constant over a wide frequency range. paragraph 6 of application note 19 details suitable stability tests for the ?nished circuit. current limit for proper operation, the current limit resistor, rcl, must be connected as shown in the external connection diagram. the minimum value is 3.9 ohms, however for optimum reliability, the resistor should be set as high as possible. the maximum practical value is 110 ohms. current limit values can be pre - dicted as follows: ilimit = vbe rcl where vbe is shown in the current limit typical graph. note that +vbe should be used to predict current through the +vs pin, -vbe for current through the -vs pin, and that they vary with case temperature. value of the current limit resistor at a case temperature of 25 can be estimated as follows: rcl = 0.7 ilimit when the ampli?er is current limiting, there may be spurious oscillation present during the current limited portion of the nega - tive half cycle. the frequency of the oscillation is not predictable and depends on the compensation, gain of the ampli?er, value of the current limit resistor, and the load. the oscillation will cease as the ampli?er comes out of current limit. safe operating area the mosfet output stage of the pa241 is not limited by second breakdown considerations as in bipolar output stages. however there are still three distinct limitations: 1. voltage withstand capability of the transistors. 2. current handling capability of the die metalization. 3. temperature of the output mosfets. these limitations can be seen in the soa (see safe operat - ing area graphs). note that each pulse capability line shows a constant power level (unlike second breakdown limitations where power varies with voltage stress). these lines are shown for a case temperature of 25c and correspond to thermal resistances of 5.2c/w for the pa241ce and df and 10.4c/w for the pa241dw respectively. pulse stress levels for other case temperatures can be calculated in the same manner as dc power levels at different temperatures. the output stage is protected against transient ?yback by the parasitic diodes of the output stage mosfet structure. however, for protection against sustained high energy ?yback external fast-recovery diodes must be used. heatsinking the pa241df package has a large exposed integrated copper heatslug to which the monolithic ampli?er is directly attached. the solder connection of the heatslug to a minimum of 1 square inch foil area on the printed circuit board will result in thermal performance of 25c/w junction to air rating of the pa241df. solder connection to an area of 1 to 2 square
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 6 pa241 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. pa241u rev b august 2005 ? 2005 apex microtechnology corp. ???????????????????????????????? ? ??? ? ???? ?? ?? ?? ?? ??? ??? ??? ??? ?????????????????????? ? ?????? ? ?????? ? ? ? ? ?? ?? ?? ?? ?? ??? ????? ? ???????? ????? ? ??????? ?? ????????????????????????????????? ?????????????????? ????? ??? ??? ???????????????????????????????? ? ??? ? ???? ?? ?? ?? ?? ??? ??? ??? ??? ?????????????????????? ? ?????? ? ?????? ? ? ? ? ?? ?? ?? ?? ?? ??? ????? ? ???????? ????? ? ??????? ?? ????????????????????????????????? ??????????? ????? ??? ??? operating considerations +vs -vs out +vs -vs z1 z2 -in +in q1 q2 inches is recommended. this may be adequate heatsinking but the large number of variables involved suggest temperature measurements be made on the top of the package. do not allow the temperature to exceed 85c. figure 1 overvoltage protection although the pa241 can withstand differential input voltages up to 16v, in some applications additional external protection may be needed. differential inputs exceeding 16v will be clipped by the protection circuitry. however, if more than a few milliamps of current is available from the overload source, the protection circuitry could be destroyed. for differential sources above 16v, adding series resistance limiting input current to 1ma will prevent damage. alternatively, 1n4148 signal diodes connected anti-parallel across the input pins is usually suf?cient. in more demanding applications where bias current is impor - tant, diode connected jfets such as 2n4416 will be required. see q1 and q2 in figure 1. in either case the differential input voltage will be clamped to 0.7v. this is suf?cient overdrive to produce the maximum power bandwidth. in the case of inverting circuits where the +in pin is grounded, the diodes mentioned above will also afford protection from excessive common mode voltage. in the case of non-invert - ing circuits, clamp diodes from each input to each supply will provide protection. note that these diodes will have substantial reverse bias voltage under normal operation and diode leak - age will produce errors. some applications will also need over-voltage protection devices connected to the power supply rails. unidirectional zener diode transient suppressors are recommended. 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. see z1 and z2 in figure 1. application references: for additional technical information please refer to the fol - lowing application notes: an1: general operating considerations an3: bridge circuit drives an25: driving capacitive loads an38: loop stability with reactive loads
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