PA07,
I
PA07A
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o
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P r o d u c t I
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PA07 • PA07A
PA07 • PA07A
FET Input Power Operational Amplifier
FEATURES
• Low bias current — Fet Input
• Protected outPut staGe — Thermal
Shutoff
• exceLLent Linearity — class a/b output
• wide suPPLy ranGe — ±12V to ±50V
• HiGH outPut current — ±5a Peak
APPLICATIONS
• Motor, VaLVe and actuator controL
• MaGnetic deFLection circuits uP to 4a
• Power transducers uP to 100kHz
• teMPerature controL uP to 180w
• ProGraMMabLe Power suPPLies uP to 90V
• audio aMPLiFiers uP to 60w rMs
8-Pin to-3
PacKaGe styLe ce
TYPICAL APPLICATION
C
L
R
L
R
F1
R
F2
+32V
C
F
R
CL+
.68Ω
PA07
+V
R
CL–
.68Ω
–32V
–V
PD1
PD2
LIGHT
V = 28
EMF = 14V
R
W
= 14Ω
MOTOR
descriPtion
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 out-
put 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
Q1
Q5
Q8
Q9
C3
5
4
Q12A
Q15
Q18
6
Q12B
Q10
C4
D3
Q17A
Q16
D2
C2
Q7
1
Q11
Q19
Q17B
8
Q2
C1
Q6A
Q6B
2
D1
Q4
Q3
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 momen-
tary 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.
EXTERNAL CONNECTIONS
+V
S
3
CL+
2
1
R
CL+
OUT
OUTPUT
R
T
+IN
4
TOP VIEW
R
S
–IN
5
6
7
8
CL–
R
CL–
–V
S
BAL
R
S
= ( V
S
+ + –V
S
) R
T
/1.6
NOTE: Input offset voltage trim optional. R
T
= 10KΩ MAX
PA07U
http://www.cirrus.com
Copyright © Cirrus Logic, Inc. 2009
(All Rights Reserved)
MAY 2009
1
APEX − PA07UREVP
CIRRUS [ CIRRUS LOGIC ]
