POWER OPERATIONAL AMPLIFIER
MICROTECHNOLOGY
HTTP://WWW.APEXMICROTECH.COM (800) 546-APEX (800) 546-2739
FEATURES
• EXTENDED SUPPLY RANGE
UP TO ±175V or
350V TOTAL
• PROVIDES PA08 PERFORMANCE
UP TO ±150mA
PROGRAMMABLE CURRENT LIMIT
LOW DRIFT FET INPUT
APPLICATIONS
• PROGRAMMABLE POWER SUPPLIES UP TO 340V
• ELECTROSTATIC TRANSDUCERS & DEFLECTION
• PIEZO ELECTRIC TRANSDUCERS
• HIGH VOLTAGE INSTRUMENTATION
DESCRIPTION
The PA08V is an extended supply range operational amplifier capable of output voltage swings of ±170V with dual
supplies or 340V total supply voltage on single or non-symmetric supplies.
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 PA08 features an
unprecedented supply range and excellent supply rejection. The
output stage is biased class A-B for linear operation. Internal
phase compensation assures stability at all gain settings. The
safe operating area (SOA) can be observed with all types of
loads by choosing the appropriate current limiting resistors. For
operation into inductive loads, two external flyback pulse protection diodes are recommended. 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 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”.
SPECIFICATIONS
Specifications of the standard PA08 apply with the benefit of
supply ratings being extended to ±175V. Design changes
enabling the total supply rating of 350V have no effect on the
shape of the typical performance graphs.
PA08V
Please consult the PA08 data sheet for basic information on
this amplifier, plus the application notes in this APEX DATA
BOOK, for recommendations on stability, current limiting,
heatsinks, bypassing, and suggestions for circuit functions.
SAFE OPERATING AREA CURVE (SOA)
150
(mA)
S
100
80
OR –V
S
50
40
30
20
15
100
90
OUTPUT CURRENT FROM +V
SUPPLY TO OUTPUT DIFFERENTIAL VOLTAGE (V)
150125
EQUIVALENT SCHEMATIC
3
7
Q1
Q5
Q8
5
Q12A Q12B
4
Q2
Q9
C4
D1
C2
Q10
steady state
175
200
Q3
Q4
C3
Q11
t = 5ms
t = 0.5ms
t = 1ms
250
C1
Q7
Q19
t = 200µs
300
Q6
Q17
350
2
1
8
GENERAL CONSIDERATIONS
SAFE OPERATING AREA
Q15
D2
Q16
The extended safe operating area is as follows:
When operating on ±175V, maximum safe values of capaci-
6
tive and inductive loading are .2µF and 200mH. Maximum safe
current limit for a short to common is 50mA, and for a short to
supply rails, the maximum is 15mA.
This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specifications are subject to change without notice.
PA08VU REV. F FEBRUARY 1998 © 1998 Apex Microtechnology Corp.