Low Bias, 5A, 100V Power Amplifier0 pages

PA07 • PA07A
PA07 • PA07A

PA07, PA07A

FET Input Power Operational Amplifier
FEATURES
•t LOW BIAS CURRENT — FET Input
•t PROTECTED OUTPUT STAGE — Thermal Shutoff
•t EXCELLENT LINEARITY — Class A/B Output
•t WIDE SUPPLY RANGE — ±12V TO ±50V
•t HIGH OUTPUT CURRENT — ±5A Peak

8-PIN TO-3
PACKAGE STYLE CE

APPLICATIONS
•t MOTOR, VALVE AND ACTUATOR CONTROL
•t MAGNETIC DEFLECTION CIRCUITS UP TO 4A
•t POWER TRANSDUCERS UP TO 100kHz
•t TEMPERATURE CONTROL UP TO 180W
•t PROGRAMMABLE POWER SUPPLIES UP TO 90V
•t AUDIO AMPLIFIERS UP TO 60W RMS

TYPICAL APPLICATION
CL
RL

R F1
R F2

PA07

The PA07 is a high voltage, high output current operational
amplifier designed to drive resistive, inductive and capacitive
loads. For optimum linearity, especially at low levels, the output stage is biased for class A/B operation using a thermistor
compensated base-emitter voltage multiplier circuit. A thermal
shutoff circuit protects against overheating and minimizes
heatsink requirements for abnormal operating conditions. The
safe operating area (SOA) can be observed for all operating
conditions by selection of user programmable current limiting
resistors. Both amplifiers are internally compensated for all
gain settings. For continuous operation under load, a heatsink
of proper rating is recommended.
This hybrid circuit utilizes thick film (cermet) 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 washers
and/or improper mounting torque will void the product warranty.
Please see “General Operating Considerations”
.

EQUIVALENT SCHEMATIC
3
7
Q2

D1

Q3

C1
Q6B
2

C2

Q9

+V

Q10

–32V
–V

PD1

5
4

Q12A

Q19

RS= (│VS+│+│–VS│) RT/1.6

CL–

Q12B

Q16
Q18

7

–VS

6

5 –IN

RS

TOP VIEW

Q17B
Q17A

Q15

BAL

8

RCL-

8

C4
D3

PD2

Negates optoelectronic instabilities
Lead network minimizes overshoot
SEQUENTIAL POSITION CONTROL
Position is sensed by the differentially connected photo
diodes, a method that negates the time and temperature
variations of the optical components. Off center positions
produce an error current which is integrated by the op amp
circuit, driving the system back to center position. A momentary switch contact forces the system out of lock and then the
integrating capacitor holds drive level while both diodes are
in a dark state. When the next index point arrives, the lead
network of C1 and R1 optimize system response by reducing
overshoot. The very low bias current of the PA07 augments
performance of the integrator circuit.

Q7

Q11

LIGHT

.68Ω

1
C3

MOTOR

R CL–

EXTERNAL CONNECTIONS

Q6A

Q4
Q5
Q8

V = 28
EMF = 14V
R W = 14Ω

.68Ω

DESCRIPTION

Q1

CF
R CL+

+32V

4

OUTPUT
OUT

D2

RCL+

1
2

CL+

+IN

RT

3
+VS

6

NOTE: Input offset voltage trim optional. RT = 10KΩ MAX

PA07U
www.apexanalog.com

Copyright © Apex Microtechnology, Inc. 2012
(All Rights Reserved)

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