PA119CE Datasheet, PDF (1/5 Pages) Cirrus Logic – Video Power Operational Amplifier

Product
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PA11P9AC11E9C• EPA• P1A1191C9ECAEA
Video Power Operational Amplifier
FEATURES
• VERY FAST SLEW RATE — 900 V/µs
• POWER MOS TECHNOLOGY — 4A peak rating
• LOW INTERNAL LOSSES — 0.75V at 2A
• PROTECTED OUTPUT STAGE — Thermal Shutoff
• WIDE SUPPLY RANGE — ±15V TO ±40V
APPLICATIONS
• VIDEO DISTRIBUTION AND AMPLIFICATION
• HIGH SPEED DEFLECTION CIRCUITS
• POWER TRANSDUCERS UP TO 5 MHz
• MODULATION OF RF POWER STAGES
• POWER LED OR LASER DIODE EXCITATION
DESCRIPTION
The PA119 is a high voltage, high current operational ampli-
fier optimized to drive a variety of loads from DC through the
video frequency range. Excellent input accuracy is achieved
with a dual monolithic FET input transistor which is cascoded
by two high voltage transistors to provide outstanding common
mode characteristics. All internal current and voltage levels
are referenced to a zener diode biased on by a current source.
As a result, the PA119 exhibits superior DC and AC stability
over a wide supply and temperature range.
High speed and freedom from second breakdown is assured
by a complementary power MOS output stage. For optimum
linearity, especially at low levels, the power MOS transistors
are biased in a class A/B mode. Thermal shutoff provides
full protection against overheating and limits the heatsink
requirements to dissipate the internal power losses under
normal operating conditions. A built-in current limit of 0.5A
can be increased with the addition of two external resistors.
Transient inductive load kickback protection is provided by
two internal clamping diodes. External phase compensation
allows the user maximum flexibility in obtaining the optimum
slew rate and gain bandwidth product at all gain settings. A
heatsink of proper rating is recommended.
This hybrid circuit utilizes thick film (cermet) resistors, ceramic
capacitors, and silicon semiconductor chips to maximize reli-
ability, minimize size, and give top performance. Ultrasonically
bonded aluminum wires provide reliable interconnections at all
operating temperatures. The 8-pin TO-3 package is hermeti-
cally sealed and electrically isolated. The use of compress-
ible thermal washers and/or improper mounting torque will
void the product warranty. Please see “General Operating
Considerations”.
8-pin TO-3
PACKAGE STYLE CE
TYPICAL APPLICATION
This fast power driver utilizes the 900V/µs slew rate of the
PA119 and provides a unique interface with a current output
DAC. By using the DAC’s internal 1KΩ feedback resistor,
temperature drift errors are minimized, since the temperature
drift coefficients of the internal current source and the internal
feedback resistor of the DAC are closely matched. Gain of
V_OUT to I_IN is –6.5/mA. The DAC’s internal 1K resistor together
with the external 500Ω and 110Ω form a “tee network” in the
feedback path around the PA119. This effective resistance
equals 6.5KΩ . Therefore the entire circuit can be modeled
as 6.5KΩ feedback resistor from output to inverting input and
a 5mA current source into the inverting input of the PA119.
Now we see the familiar current to voltage conversion for a
DAC where V_OUT = –I_IN x R . _FEEDBACK
EQUIVALENT SCHEMATIC
3
Q3
Q5
8
Q12
5
Q17A
Q4
Q8
Q10
Q11
Q13
Q16
Q17B
Q1
Q9
Q15
D1
Q20
4
Q23
6
Q24
D2
Q25
Q2
2
Q7
1
Q19
Q21
Q22
7
TYPICAL
APPLICATION
+40V
110Ω
1K
DAC
±5mA
R_CL+
PA119
R_CL–
5.6pF
500Ω
±32.5V
Up to 4A
–40V
PA119 AS FAST POWER DRIVER
EXTERNAL CONNECTIONS
RCL+
+V 3
2
OUT
1
4
+IN
TOP
CC
VIEW
5
–IN
6
–V
8
7
RCL–
PHASE COMPENSATION
GAIN
CC
1
10
100
1000
330pF
22pF
2.2pF
none
PA11_h9_tU_{tp://www.cirrus.com}
Copyright © Cirrus Logic, Inc. 2009
(All Rights Reserved)
MAY 2009₁
APEX − PA119UREVB