CA3160 Datasheet, PDF (14/18 Pages) Intersil Corporation – 4MHz, BiMOS Operational Amplifier with MOSFET Input/CMOS Output

CA3160
+15V
100kΩ
1MΩ
30pF
7
3+
CA3160
2-
4
5
1
100kΩ
OFFSET
VOLTAGE
ADJUST
9.1kΩ
0.1µF
6
8
8.2kΩ
+15V
2200pF
0.1µF
39kΩ
2
-
7
1N914 _CA3080A
6
3+
4 ^100kΩ
0.1µF ⁵
27kΩ
DROOP
ZERO
ADJUST
500µA
1MΩ
39kΩ
8.2Ω
2
3
0.1µF
+15V
0.1µF
7
-
CA3140
6
+
4
STROBE INPUT
SAMPLE = 15V
2kΩ
HOLD = 0V
FIGURE 12A. SINGLE SUPPLY SAMPLE AND HOLD SYSTEM, INPUT 0V TO 10V
SAMPLED
OUTPUT
INPUT
SIGNAL
SAMPLED
OUTPUT
0V-
INPUT 0V-
SAMPLING
PULSES
SAMPLING
PULSES
Top Trace: Sampled Output
Center Trace: Input Signal
Bottom Trace: Sampling Pulses
Top Trace: Sampled Output
Center Trace: Input Signal
Bottom Trace: Sampling Pulses
FIGURE 12B. SAMPLE AND HOLD WAVEFORM
FIGURE 12C. SAMPLE AND HOLD WAVEFORM
FIGURE 12. SINGLE SUPPLY SAMPLE AND HOLD SYSTEM, INPUT 0V TO 10V
Single Supply Sample-and-Hold System
Figure 12 shows a single supply sample-and-hold system
using a CA3160 to provide a high input impedance and an
input voltage range of 0V to 10V. The output from the input
buffer integrator network is coupled to a CA3080A. The
CA3080A functions as a strobeable current source for the
CA3140 output integrator and storage capacitor. The
CA3140 was chosen because of its low output impedance
and constant gain-bandwidth product. Pulse “droop” during
the hold interval can be reduced to zero by adjusting the
100kΩ bias-voltage potentiometer on the positive input of the
CA3140. This zero adjustment sets the CA3080A output
voltage at its zero current position. In this sample-and-hold
circuit it is essential that the amplifier bias current be
reduced to zero to minimize output signal current during the
hold mode. Even with 320mV at the amplifier bias circuit
terminal (5) at least 1100pA of output current will be
available.
Wien Bridge Oscillator
A simple, single supply Wien Bridge oscillator using a
CA3160 is shown in Figure 13. A pair of parallel-connected
1N914 diodes comprise the gain-setting network which
standardizes the output voltage at approximately 1.1V. The
500Ω potentiometer is adjusted so that the oscillator will
always start and the oscillation will be maintained.
Increasing the amplitude of the voltage may lower the
threshold level for starting and for sustaining the oscillation,
but will introduce more distortion.
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