apex microtechnology corporation ? telephone (520) 690-8600 ? fax (520) 888-3329 ? orders (520) 690-8601 ? email prodlit@apexmicrotech.com 1 features ? high voltage operation 150v (pa82j) ? high output current 30ma (PA81J) ? low bias current, low noise fet input applications ? high impedance buffers up to 140v ? electrostatic transducer & deflection ? programmable power supplies to 145v ? biochemistry stimulators ? computer to vacuum tube interface description the pa80 series of high voltage operation ampli?ers provides an extremely wide range of supply capability with two over - lapping products. high accuracy is achieved with a cascode input circuit con?guration. all internal biasing is referenced to a zener diode. as a result, these models offer outstanding common mode and power supply rejection. the output stage operates in the class a/b mode for best linearity. internal phase compensation assures stability at all gain settings without external components. fixed internal current limits protect these ampli?ers against a short circuit to common at most supply voltages. for sustained high energy ?yback, external fast recovery diodes should be used. however, a heatsink may be necessary to maintain the proper case temperature under normal operating conditions. this hybrid circuit utilizes thick ?lm resistors, ceramic capacitors and silicon semiconductors to maximize reliabil - ity, minimize size and give top performance. ultrasonically bonded aluminum wires provide reliable interconnections at all operating temperatures. the 8-pin to-3 package (see package outlines) is hermetically sealed and isolated from the internal circuits. the use of compressible thermal washers voids the warranty. external connections ???????? ? ? ? ? ? ? ? ? ?? ? ??? ??? ??? ???? ?????? ??? ?? ? ???????????????????????????????????? ?????????????????????????????????????? typical application the pa81 and 70k ohm resistor form a current to voltage converter, accepting 1ma from a 12 bit current output digital to analog converter. the power op amp contribution to the er - ror budget is insigni?cant. at a case temperature of 70c, the combination of voltage offset and bias errors amounts to less than 31ppm of full scale range. incorporation of the optional offset trim can further reduce these errors to under 9ppm. equivalent schematic ???? ???? ????? ????? ?????????????????????????????????????? ???? ??? ??? ??? ???? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ????????????????????????????????????????? ???????????????????? ? ? ? ? ? ? ? ?? ?? ?? ?? ??? ???? ?? ?? ?? ??? ?? ?? ?? ??? ??? ?? ?? ???? ??? ?? ?? ?? ??? ?? ?? 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 specifications absolute maximum ratings PA81J pa82j supply voltage, +v s to Cv s 200v 300v output current, within soa internally limited power dissipation, internal 11.5w 11.5w input voltage, differential 150v 300v input voltage, common mode v s v s temperature, pin solder - 10 sec 300c 300c temperature, junction 150c 150c temperature range, storage C65 to +125c C65 to +125c operating temperature range, case C55 to +125c C55 to +125c PA81J pa82j parameter test conditions 2 min typ max min typ max units input offset voltage, initial t c = 25c 1.5 3 * * mv offset voltage, vs. temperature full temperature range 10 25 * * v/c offset voltage, vs. supply t c = 25c 20 * v/v offset voltage, vs. time t c = 25c 75 * v/kh bias current, initial t c = 25c 5 50 * * pa bias current, vs. supply t c = 25c .2 * pa/v offset current, initial t c = 25c 2.5 50 * * pa input impedance, dc t c = 25c 10 11 * input capacitance t c = 25c 10 * pf common mode voltage range 2 full temperature range v s C10 * v common mode rejection, dc v cm = 20v 110 * db gain open loop gain at 10hz full load 94 116 100 118 db unity gain bandwidth t c = 25c 5 * mhz power bandwidth t c = 25c, full load 60 30 khz phase margin full temperature range 45 * output voltage swing 2 t c = 25c, i pk v s C5 * v current, peak t c = 25c 30 15 ma current, limit t c = 25c 50 25 ma settling time to .1% t c = 25c, 10v step 12 * s slew rate 4 t c = 25c 20 * v/s capacitive load a v = 1 10 * nf power supply voltage full temperature range 32 75 75 70 150 150 v current, quiescent t c = 25c 6.5 8.5 6.5 8.5 ma thermal resistance, ac, junction to case 3 f > 60hz 6 * c/w resistance, dc, junction to case 3 f < 60hz 9 10 * * c/w resistance, junction to air full temperature range 30 * c/w temperature range, shutdown 150 * c temperature range, case meets full range speci?cation 0 70 * * c PA81J ? pa82j notes: * the speci?cation of pa82j is identical to the speci? cation for PA81J in applicable column to the left. 1. the power supply voltage for all speci? cations is the typ rating unless noted as a test condition. 2. +v s and Cv s denote the positive and negative supply rail respectively. total v s is measured from +v s to Cv s . 3. rating applies if the output current alternates between both output transistors at a rate faster than 60hz. 4. on the PA81J and pa82j, signal slew rates at pins 5 and 6 must be limited to less than 1v/ns to avoid damage. when faster waveforms are unavoidable, resistors in series with those pins, limiting current to 150ma will protect the ampli?er from damage. 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 PA81J ? pa82j ? ?? ?? ?? ??? ??? ?????????????? ? ????? ? ? ? ?? ?????????????? ????????????????????????????????? ??? ??? ?? ??? ??? ????????????? ??? ?? ????????????????? ?????????????????????? ? ????????? ? ????????????????? ??? ? ?? ????????????????????? ?????????????????????? ?? ?? ?? ??? ?? ???? ???? ??? ? ?????????????? ??? ??? ????????????????? ????????????????? ? ??? ?? ? ??????????????????? ?????????????? ?? ??????????????????????? ??? ????????? ???????????????????? ??? ??? ???????????????????? ??????????????????????? ??? ?? ?? ? ? ????????????????? ????????????????????? ??????????????????????????????? ?? ?? ??? ?? ??? ? ????????????????? ?????????????????????? ???????????????????????????????? ??? ?? ?? ?? ???????????? ?????????????????????????????? ? ??????????? ??? ?? ?? ?? ??? ?????????????? ?? ?? ?? ?? ?? ? ?? ?? ??? ??? ?? ???? ?? ???????????? ?????????????????????????? ? ???? ? ?? ?? ??? ?? ??? ? ?? ?? ?? ?? ??? ??? ?? ??? ???? ???? ? ?? ??? ??? ?? ??? ??? ??? ??? ? ? ??? ?? ??? ? ??? ??? ??? ?? ?? ??? ????????????????? ??? ? ?? ??? ?? ?? ???? ?? ??? ??? ??? ??? ??? ??? ?? ?? ?? ??? ??? ??? ???? ???? ???? ? ?? ??? ???? ??? ? ?? ?? ??? ???? ?? ??? ??? ??? ??? ??? ?? ?? ??? ??? ??? ?? ?? ??? ??? ??? ??? ??? ??? ? ? ? ?? ?? ?? ?? ??? ??? ??? ????? ? ????? ? ?? ? ?? ? ??????????? ????? ? ? ??????? ??????? ????? ? ? ?????? ?????? ?????????????? ????? ????? ????? ??????????????????? ? ????? ??????????????????? ? ????? ????????????????? ????? ????? ?? ?????????????????
apex microtechnology corporation ? 5980 north shannon road ? tucson, arizona 85741 ? usa ? applications hotline: 1 (800) 546-2739 4 operating considerations PA81J ? pa82j single supply operation these ampli?ers are suitable for operation from a single sup - ply voltage. the operating requirements do however, impose the limitation that the input voltages do not approach closer than 10 volts to either supply rail. this is due to the operating voltage requirements of the current sources, the half-dynamic loads and the cascode stage. refer to the simpli?ed schemat - ics.thus, single supply operation requires the input signals to be biased at least 10 volts from either supply rail. figure 3 illustrates one bias technique to achieve this. figure 4 illustrates a very common deviation from true single supply operation. the availibility of two supplies still allows ground (common) referenced signals, but also maximizes the high voltage capability of the unipolar output. this technique can utilize an existing low voltage system power supply and does not place large current demands on that supply. the 12 volt supply in this case must supply only the quiescent current of the PA81J, which is 8.5ma maximum. if the load is reactive or emf producing, the low voltage supply must also be able to absorb the reverse currents generated by the load. general please read application note 1 "general operating con - siderations" which covers stability, 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, in - ternal power dissipation, current limit and heat sink selection. the "application notes" and "technical seminar" sections contain a wealth of information on speci?c 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) for the pa80j and PA81J, the combination of voltage capa - bility and internal current limits mandate that the devices are safe for all combinations of supply voltage and load. on the pa82j, any load combination is safe up to a total supply of 250 volts. when total supply voltage equals 300 volts, the device will be safe if the output current is limited to 10 milliamps or less. this means that the pa82j used on supplies up to 125 volts will sustain a short to common or either supply without danger. when using supplies above 125 volts, a short to one of the supplies will be potentially destructive. when us - ing single supply above 250 volts, a short to common will be potentially destructive. safe supply voltages do not imply disregard for heatsinking. the thermal calculations and the use of a heatsink are required in many applications to maintain the case temperature within the speci?ed operating range of 0 to 70c. exceeding this case temperature range can result in an inoperative circuit due to excessive input errors or activation of the thermal shutdown. inductive loads two external diodes as shown in figure 2, are required to protect these ampli?ers against ?yback (kickback) pulses exceeding the supply voltage of the ampli?er when driving in - ductive loads. for component selection, these external diodes must be very quick, such as ultra fast recovery diodes with no more than 200 nanoseconds of reverse recovery time. be sure the diode voltage rating is greater than the total of both supplies. the diode will turn on to divert the ?yback energy into the supply rails thus protecting the output transistors from destruction due to reverse bias. a note of caution about the supply. the energy of the ?yback pulse must be absorbed by the power supply. as a result, a transient will be superimposed on the supply voltage, the magnitude of the transient being a function of its transient impedance and current sinking capability. if the supply voltage plus transient exceeds the maximum supply rating, or if the ac impedance of the supply is unknown, it is best to clamp the output and the supply with a zener diode to absorb the transient. ?? ? ?? ? ????????? ??????????? ?????????????? ????? ????? ????? ????????? ??????????? ???????????????? ??? ????????? ????? ????? ?????? ?????? ???????? ????? ????? ????? ???? ????? ????? ????? ????????? ????????????? ???????? ???? ??? ??????? ???? 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. pa81_82ju rev h march 2001 ? 2001 apex microtechnology corp.
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