CA3060 Intersil, CA3060 Datasheet - Page 10

• Manufacturer Part Number: CA3060
• Description: 110kHz / Operational Transconductance Amplifier Array
• Manufacturer: Intersil

The circuit diagram of a tri-level comparator appears in Figure
22. Power is provided for the CA3060 via terminal 3 and 8 by
current (I
limit and upper limit reference voltages are selected by appro-
priate adjustment of potentiometers R
When resistors R
intermediate limit reference voltage is automatically estab-
lished at a value midway between the lower limit and upper
limit values. Appropriate variation of resistors R
mits selection of other values of intermediate limit voltage.
Input signal (E
nals 5, 12 and 14. The “SET” output lines trigger the appropri-
ate flip-flop whenever the input signal reaches a limit value.
When the input signal returns to an intermediate value, the
common flip-flop “RESET” line is energized. The loads in the
circuits, shown in Figure 22 are 5V, 25mA lamps.
L = 10kH
ENCE VOLTAGE
TERMINAL
TERMINAL
INTERMEDIATE
FIGURE 23. FUNCTIONAL BLOCK DIAGRAM OF A TRI-LEVEL
FIGURE 24. TWO OPERATIONAL TRANSCONDUCTANCE
6V supplies and the built-in regulator provides amplifier bias
LIMIT REFER-
LOWER LIMIT
UPPER LIMIT
REFERENCE
REFERENCE
A
B
VOLTAGE
VOLTAGE
SIGNAL
INPUT
ABC
COMPARATOR
AMPLIFIERS OF THE CA3060 CONNECTED AS A
GYRATOR IN AN ACTIVE FILTER CIRCUIT
) to the three amplifiers via terminal 1. Lower
20k
2M
20k
S
) is applied to the three comparators via termi-
3
and R
DETECTOR
TRI-LEVEL
14
13
CA3060
9
+
+
+
-
-
-
4
560k
560k
V-
V+
are equal in value (as shown), the
AMP 1
SET
RESET
SET
AMP 2
15
10
3
8
V+ = 6V
V- = -6V
FLIP-FLOP
FLIP-FLOP
CA3086
CA3086
1
V+
V-
and R
100k
16
12
11
2
V+
V+
3
, respectively.
(WHEN LOWER
(WHEN UPPER
LIMIT IS
REACHED)
LIMIT IS
REACHED)
and R
2M
20
k
POSITIVE
OUTPUT
POSITIVE
OUTPUT
4
3 F
20
k
CA3060
per-
3-10
Active Filters - Using the CA3060 as a Gyrator
The high output impedance of the OTAs makes the CA3060
ideally suited for use as a gyrator in active filter applications.
Figure 24 shows two OTAs of the CA3060 connected as a
gyrator in an active filter circuit. The OTAs in this circuit can
make a 3 F capacitor function as a floating 10kH inductor
across Terminals A and B. The measured Q of 13 (at a
frequency of 1Hz) of this inductor compares favorably with a
calculated Q of 16. The 20k
circuit extend the dynamic range of the OTA by a factor of
100. The 100k
inductor by varying the g
the gyration resistance.
Three Channel Multiplexer
Figure 25 shows a schematic of a three channel multiplexer
using a single CA3060 and a 3N153 MOSFET as a buffer
and power amplifier.
When the CA3060 is connected as a high input impedance
voltage follower, and strobe “ON”, each amplifier is activated
and the output swings to the level of the input of the
amplifier. The cascade arrangement of each CA3060
amplifier with the MOSFET provides an open loop voltage
gain in excess of 100dB, thus assuring excellent accuracy in
the voltage follower mode with 100% feedback. Operation at
resistance in series with the amplifier bias current (I
minal of each amplifier should be decreased to maintain
100 A of strobe “ON” current at this lower supply voltage.
Second, the drain resistance for the MOSFET should be
6V is also possible with several minor changes. First, the
2k
2k
2k
FIGURE 25. THREE CHANNEL MULTIPLEXER
2k
2k
2k
STROBE
STROBE
STROBE
300k
12
11
13
14
300k
300k
4
5
potentiometer, across V+ and V-, tunes the
V+ = 15V
+
6
+
+
-
-
-
V- = -15V
10
15
3
8
21
0.02
of the OTAs, thereby changing
F
to 2M
0.01 F
16
7
9
+15V
-15V
390
0.001 F
attenuators in this
3
STROBE “ON”
STROBE “OFF”
V+ = 15V
V- = -15V
ABC
4
2
OUTPUT
3k
3N153
) ter-