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 8-PIN TO-3 PACKAGE STYLE CE DESCRIPTION The PA80 series of high voltage operation amplifiers provides an extremely wide range of supply capability with two overlapping products. High accuracy is achieved with a cascode input circuit configuration. 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 amplifiers against a short circuit to common at most supply voltages. For sustained high energy flyback, 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 film resistors, ceramic capacitors and silicon semiconductors 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 (see Package Outlines) is hermetically sealed and isolated from the internal circuits. The use of compressible thermal washers voids the warranty. 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 error budget is insignificant. 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 EXTERNAL CONNECTIONS APEX MICROTECHNOLOGY CORPORATION * TELEPHONE (520) 690-8600 * FAX (520) 888-3329 * ORDERS (520) 690-8601 * EMAIL prodlit@apexmicrotech.com 1 PA81J * PA82J ABSOLUTE MAXIMUM RATINGS ABSOLUTE MAXIMUM RATINGS SPECIFICATIONS SPECIFICATIONS PARAMETER TEST CONDITIONS 2 INPUT OFFSET VOLTAGE, initial OFFSET VOLTAGE, vs. temperature OFFSET VOLTAGE, vs. supply OFFSET VOLTAGE, vs. time BIAS CURRENT, initial BIAS CURRENT, vs. supply OFFSET CURRENT, initial INPUT IMPEDANCE, DC INPUT CAPACITANCE COMMON MODE VOLTAGE RANGE2 COMMON MODE REJECTION, DC TC = 25C Full temperature range TC = 25C TC = 25C TC = 25C TC = 25C TC = 25C TC = 25C TC = 25C Full temperature range VCM = 20V GAIN OPEN LOOP GAIN at 10Hz UNITY GAIN BANDWIDTH POWER BANDWIDTH PHASE MARGIN Full load TC = 25C TC = 25C, full load Full temperature range OUTPUT VOLTAGE SWING2 CURRENT, peak CURRENT, limit SETTLING TIME to .1% SLEW RATE4 CAPACITIVE LOAD TC = 25C, IPK TC = 25C TC = 25C TC = 25C, 10V step TC = 25C AV = 1 POWER SUPPLY VOLTAGE CURRENT, quiescent Full temperature range TC = 25C THERMAL RESISTANCE, AC, junction to case3 RESISTANCE, DC, junction to case3 RESISTANCE, junction to air TEMPERATURE RANGE, shutdown TEMPERATURE RANGE, case NOTES: * 1. 2. 3. 4. CAUTION PA81J PA82J 200V 300V Internally Limited 11.5W 11.5W 150V 300V VS VS 300C 300C 150C 150C -65 to +125C -65 to +125C -55 to +125C -55 to +125C SUPPLY VOLTAGE, +VS to -VS OUTPUT CURRENT, within SOA POWER DISSIPATION, internal INPUT VOLTAGE, differential INPUT VOLTAGE, common mode TEMPERATURE, pin solder - 10 sec TEMPERATURE, junction TEMPERATURE RANGE, storage OPERATING TEMPERATURE RANGE, case MIN VS-10 94 VS-5 30 32 F > 60Hz F < 60Hz Full temperature range Meets full range specification 0 PA81J TYP 1.5 10 20 75 5 .2 2.5 1011 10 MAX 3 25 50 50 * 110 116 5 60 45 100 * 15 50 12 20 10 75 6.5 6 9 30 150 MIN 75 8.5 70 10 70 * PA82J TYP MAX UNITS * * * mV V/C V/V V/kh pA pA/V pA pF V dB 118 * 30 * dB MHz kHz 25 * * * V mA mA s V/s nF * * * * * * * * * 150 6.5 * * * * * * 150 8.5 * * V mA C/W C/W C/W C C The specification of PA82J is identical to the specification for PA81J in applicable column to the left. The power supply voltage for all specifications is the TYP rating unless noted as a test condition. +VS and -VS denote the positive and negative supply rail respectively. Total VS is measured from +VS to -VS. Rating applies if the output current alternates between both output transistors at a rate faster than 60Hz. 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 amplifier 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. APEX MICROTECHNOLOGY CORPORATION * 5980 NORTH SHANNON ROAD * TUCSON, ARIZONA 85741 * USA * APPLICATIONS HOTLINE: 1 (800) 546-2739 2 PA81J * PA82J TYPICAL PERFORMANCE GRAPHS APEX MICROTECHNOLOGY CORPORATION * TELEPHONE (520) 690-8600 * FAX (520) 888-3329 * ORDERS (520) 690-8601 * EMAIL prodlit@apexmicrotech.com 3 OPERATING CONSIDERATIONS PA81J * PA82J GENERAL Please read Application Note 1 "General Operating Considerations" which covers stability, supplies, heat sinking, mounting, current limit, SOA interpretation, and specification interpretation. 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) For the PA80J and PA81J, the combination of voltage capability 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 using 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 specified 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 amplifiers against flyback (kickback) pulses exceeding the supply voltage of the amplifier when driving inductive 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 flyback 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 flyback 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. SINGLE SUPPLY OPERATION These amplifiers are suitable for operation from a single supply 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 simplified schematics.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. This data sheet has been carefullyCORPORATION checked and is believed to be NORTH reliable, however, no responsibility is assumed for possible inaccuracies omissions. All specifications HOTLINE: are subject to1change without notice. APEX MICROTECHNOLOGY * 5980 SHANNON ROAD * TUCSON, ARIZONA 85741 *orUSA * APPLICATIONS (800) 546-2739 4 PA81_82JU REV H MARCH 2001 (c) 2001 Apex Microtechnology Corp.