CA3290A Intersil, CA3290A Datasheet - Page 6

• Manufacturer Part Number: CA3290A
• Description: BiMOS Dual Voltage Comparators
• Manufacturer: Intersil

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.
Typical Performance Curves
R
1M
1M
P
P
FIGURE 8. SUPPLY CURRENT vs SUPPLY VOLTAGE (BOTH
+15V
is the parallel combination of the two 1M resistors
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
FIGURE 6. LOW FREQUENCY MULTIVIBRATOR
0
0
1
R
20M
R
0.36
) may be used for long time delays with relatively
C
1
2
3
F
L
AMPLIFIERS)
=
5
CA3290
+
-
+15V
10
1M
R
8
4
2
TOTAL SUPPLY VOLTAGE (V)
A
15
15k
1
20
1
6
+15V
1M
25
t
t
=
=
30
Period
2R
5
6
1
1M
Clog e
35
CA3290
+
-
=
40
10s
2R P
----------- -
A
-55
R 2
125
3.3k
2
o
45
o
25
CA3290, CA3290A
C
C
+
+15V
o
1
C
7
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
the lower limit (V
determined by the R
INPUT
FIGURE 9. INPUT CURRENT vs INPUT COMMON MODE
-10
-15
-20
-25
-30
-5
+15V
0
0
T
V+ = +30V, V- = GND
A
VOLTAGE
FIGURE 7. WINDOW COMPARATOR
= 25
47k
47k
100k
100k
5
L
R
R
o
) but below the upper limit (V
INPUT COMMON MODE VOLTAGE (V)
1
2
C
1
/R
V
V
10
U
L
2
R
6.8k
/R
3
2
3
6
5
A
A
3
2
15
1
resistor divider.
CA3290
CA3290
+
+
-
-
+15V
20
8
4
25
3.9k
1
7
U
30
), as
35
2N2102
670
LED