HA17524P Datasheet, PDF (10/18 Pages) Hitachi Semiconductor – Switching Regulator Controller

HA17524P/FP
Push Pull Switching Regulator: Figure 12 shows the circuit configuration of push-pull switching regulator
that uses transformer. This system is suited for high power. Output transistors inside HA17524 can drive
external switching transistors.
5kΩ
5kΩ
0.1µF
2kΩ
0.01µF
V_CC = 28V
5kΩ
V_CC
INV.
Input
NON-INV.
5kΩ ^Input
V_REF
1kΩ
1W
E₁
C₁
C₂
R_T
E₂
C_T
SHUT
DOWN
OSC Out
CL(+)
CL(–)
COMP
GND
1kΩ
1W
1kΩ
1kΩ
0.001µF
20kΩ
0.1Ω
20T
5T
20T
5T
+
− ^100µF
1mH
1,500µF
+
− ^{5V, 5A}
Figure 12 Push-Pull Switching Regulator
Note
Compared with conventional series regulators, switching regulators generate high frequency noise by
switching current quickly. To reduce noise
1. As a general rule, insert line filter to reduce noise at the input.
2. To reduce noise at the output:
a. Twist output wiring together.
b. Do not bundle power source and output wiring.
c. Insert capacitor should be inserted at the load side.
d. Ground the power frame.
3. When choosing external parts (external switching transistor, diode, coil, etc) consider their capacitance
and characteristics.
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