PA84

The PA84 is a high voltage operational amplifier designed for output voltage swings up to ±145V with a dual supply or 290V with a single supply. Two versions are available. The new PA84S, fast settling amplifier can absorb differential input overvoltages up to ±50V while the established PA84 and PA84A can handle differential input overvoltages of up to ±300V. Both versions are protected against common mode transients and overvoltages up to the supply rails. High accuracy is achieved with a cascode input circuit configuration. All internal biasing is referenced to a zener diode fed by a FET constant current source. As a result, the PA84 features an unprecedented supply range and excellent supply rejection. The output stage is biasedon for linear operation. External phase compensation allows for user flexibility in obtaining the maximum slew rate. Fixed current limits protect these amplifiers against shorts to common at supply voltages up to 150V. For operation into inductive loads, two external flyback pulse protection diodes are recommended. However, a heatsink may be necessary to maintain the proper case temperature under normal operating conditions.

This hybrid integrated circuit utilizes a beryllia (BeO) substrate, thick film resistors, ceramic capacitors and semiconductor chips 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 electrically isolated. The use of compressible thermal isolation washers and/or improper mounting torque will void the product warranty. Please see "General Operating Considerations".