ICL8038AMJD HARRIS [Harris Corporation], ICL8038AMJD Datasheet - Page 7

• Manufacturer Part Number: ICL8038AMJD
• Description: Precision Waveform Generator/ Voltage Controlled Oscillator
• Manufacturer: HARRIS [Harris Corporation]

Typical Applications
The sine wave output has a relatively high output impedance
(1k
and amplitude adjustment. A simple op amp follower could
also be used.
With a dual supply voltage the external capacitor on Pin 10 can
be shorted to ground to halt the ICL8038 oscillation. Figure 7
shows a FET switch, diode ANDed with an input strobe signal
to allow the output to always start on the same slope.
To obtain a 1000:1 Sweep Range on the ICL8038 the volt-
age across external resistors R
nearly zero. This requires that the highest voltage on control
Pin 8 exceed the voltage at the top of R
hundred mV. The Circuit of Figure 8 achieves this by using a
diode to lower the effective supply voltage on the ICL8038.
The large resistor on pin 5 helps reduce duty cycle variations
with sweep.
The linearity of input sweep voltage versus output frequency
can be significantly improved by using an op amp as shown
in Figure 9.
FIGURE 6. SINE WAVE OUTPUT BUFFER AMPLIFIERS
7
8
7
8
Typ). The circuit of Figure 6 provides buffering, gain
11
4
FIGURE 7. STROBE TONE BURST GENERATOR
10
4
R
R
C
A
A
ICL8038
ICL8038
5
5
R
R
B
B
C
10
11
6
-15V
9
2
2N4392
2
A
AMPLITUDE
and R
1N914
100K
B
A
100K
must decrease to
OFF
4.7K
and R
1N914
15K
ON
+
-
741
+15V (+10V)
-15V (-10V)
B
STROBE
by a few
20K
ICL8038
V+
V+
V-
8-159
IGURE 8. VARIABLE AUDIO OSCILLATOR, 20Hz TO 20kHzY
FREQ.
10K
20K
15M
0.1 F
8
10
5
4.7K
0.0047 F
1K
DUTY CYCLE
1N457
ICL8038
11
4
4.7K
12
6
100K
DISTORTION
9
3
2
15K
+10V
-10V