PA81J - High Voltage Power Operational Amplifier
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 is hermetically sealed and isolated from the internal circuits. The use of compressible thermal washers voids the warranty.
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 70°C, 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.
• HIGH VOLTAGE OPERATION — ±150V (PA82J)
• HIGH OUTPUT CURRENT — ±30mA (PA81J)
• LOW BIAS CURRENT, LOW NOISE — FET Input
• HIGH IMPEDANCE BUFFERS UP TO ±140V
• ELECTROSTATIC TRANSDUCER & DEFLECTION
• PROGRAMMABLE POWER SUPPLIES TO ±145V
• BIOCHEMISTRY STIMULATORS
• COMPUTER TO VACUUM TUBE INTERFACE
- APEX Microtechnology product -