CA3524E Intersil, CA3524E Datasheet - Page 9

• Manufacturer Part Number: CA3524E
• Description: REGUL. PULSE WIDTH MODULATOR
• Manufacturer: Intersil

Specifications of CA3524E

• Rohs Status: RoHS non-compliant
• Other names: CA3524

Output Section
The CA1524 series outputs are two identical n-p-n
transistors with both collectors and emitters uncommitted.
Each output transistor has antisaturation circuitry that
enables a fast transient response for the wide range of
oscillator frequencies. Current limiting of the output section
is set at 100mA for each output and 100mA total if both
outputs are paralleled. Having both emitters and collectors
available provides the versatility to drive either n-p-n or p-n-p
external transistors. Curves of the output saturation voltage
as a function of temperature and output current are shown in
Figures 8 and 9, respectively. There are a number of output
configurations possible in the application of the CA1524 to
voltage regulator circuits which fall into three basic
classifications:
Device Application Suggestions
For higher currents, the circuit of Figure 10 may be used with
an external p-n-p transistor and bias resistor. The internal
regulator may be bypassed for operation from a fixed 5V
supply by connecting both terminals 15 and 16 to the input
voltage, which must not exceed 6V.
FIGURE 10. CIRCUIT FOR EXPANDING THE REFERENCE
V+
FIGURE 9. TYPICAL OUTPUT SATURATION VOLTAGE AS A
GND
1. Capacitor-diode coupled voltage multipliers
2. Inductor-capacitor single-ended circuits
3. Transformer-coupled circuits
100
2.0
1.5
1.0
0.5
0
Q1
FUNCTION OF OUTPUT CURRENT
CURRENT CAPABILITY
0
T
V+ = 8V to 40V
A
15
= +25
20
OUTPUT CURRENT, I
o
C
REFERENCE
SECTION
CA1524
40
8
60
L
(mA)
16
10 F
CA1524, CA2524, CA3524
80
+
-
V
I
DEPENDING
ON CHOICE
FOR Q1
REF
L
100
TO I
A
9
The internal 5V reference can be used for conventional regu-
lator applications if divided as shown in Figure 11. If the error
amplifier is connected as a unity gain amplifier, a fixed duty
cycle application results.
To provide an expansion of the dead time without loading the
oscillator, the circuit of Figure 13 may be used.
FIGURE 12. CIRCUIT TO ALLOW EXTERNAL BYPASS OF THE
FIGURE 13. CIRCUIT FOR EXPANSION OF DEAD TIME, WITH-
GND
FIGURE 11. ERROR AMPLIFIER BIASING CIRCUITS
V
GND
V
REF
V+ CANNOT
EXCEED 6V
REF
NOTE: V+ Should Be in the 5V Range
5K
5K
REFERENCE REGULATION
OUT USING A CAPACITOR ON PIN 3 OR WHEN A
LOW VALUE OSCILLATOR CAPACITOR IS USED
5K
5K
And Must Not Exceed 6V
5K
15
16
8
R1
V
T
R1
R2
2
1
REFERENCE
SECTION
2
1
CA1524
V
R2
R1 + R2
O
R1R2
16
8
9
2.5V (R1 + R2)
+
+
-
-
V
POSITIVE
OUTPUT
VOLTAGES
REF
R1
= 2.5KW
NEGATIVE
OUTPUT
VOLTAGES