ca3290 Intersil Corporation, ca3290 Datasheet - Page 6

• Manufacturer Part Number: ca3290
• Description: Bimos Dual Voltage Comparators With Mosfet Input, Bipolar Output
• Manufacturer: Intersil Corporation

constant to insure constant reverse voltage bias on the
photo diode.
Low-Frequency Multivibrator
In this application, one half of the CA3290 is used as a
conventional multivibrator circuit. Because of the extremely
high input impedance of this device, large values of timing
resistor (R
small leakage timing capacitors. The second half of the
CA3290 is used as an output buffer to insure that the
multivibrator frequency will not be affected by output loading.
R
connected between +15V and GND.
Window Comparator
Both halves of the CA3290 can be used in a high input
impedance window comparator as shown in Figure 7. The
LED will be turned “on” whenever the input signal is above
R
1MΩ
1MΩ
R
P
P
2MΩ
R
1
+15V
1.5MΩ
2
is the parallel combination of the two 1MΩ resistors
FIGURE 5. LIGHT CONTROLLED ONE-SHOT TIMER
+15V
FIGURE 6. LOW FREQUENCY MULTIVIBRATOR
C30809
15
kΩ
15kΩ
1
R
20MΩ
0.36
µF
) may be used for long time delays with relatively
C
3
2
1
2
3
A
+15V
1
CA3290
+
CA3290
-
+
-
+15V
1MΩ
8
4
R
8
4
1MΩ
2
A
15kΩ
1
+15V
1
1
1N914
0.01µF
+15V
6
+15V
1MΩ
140kΩ
t
t
1N914
60MΩ
=
=
Period
2R
5
6
1
1MΩ
5
6
Clog e
A
10kΩ
CA3290
+
-
2
=
X 60s TIME
CA3290
+
-
10s
1.0µF



2R P
----------- -
A
R 2
3.3kΩ
2
3.3kΩ
CA3290, CA3290A
+
+15V
1
+15V
7



7
the lower limit (V
determined by the R
INPUT
+15V
FIGURE 7. WINDOW COMPARATOR
47kΩ
47kΩ
100kΩ
100kΩ
L
R
R
) but below the upper limit (V
1
2
1
/R
V
V
U
L
2
R
6.8kΩ
/R
3
2
3
6
5
A
A
3
2
1
resistor divider.
CA3290
CA3290
+
+
-
-
+15V
8
4
3.9kΩ
1
7
U
), as
2N2102
670Ω
LED