SG1526 Datasheet, PDF (1/9 Pages) Microsemi Corporation – REGULATING PULSE WIDTH MODULATOR

SG1526/SG2526/SG3526
REGULATING PULSE WIDTH MODULATOR
DESCRIPTION
The SG1526 is a high performance monolithic pulse width modulator
circuit designed for fixed-frequency switching regulators and other
power control applications. Included in an 18-pin dual-in-line package
are a temperature compensated voltage reference, sawtooth oscillator,
error amplifier, pulse width modulator, pulse metering and steering logic,
and two low impedance power drivers. Also included are protective
features such as soft-start and undervoltage lockout, digital current
limiting, double pulse inhibit, a data latch for single pulse metering,
adjustable deadtime, and provision for symmetry correction inputs. For
ease of interface, all digital control ports are TTL and B-series CMOS
compatible. Active LOW logic design allows wired-OR connections for
maximum flexibility. This versatile device can be used to implement
single-ended or push-pull switching regulators of either polarity, both
transformerless and transformer coupled. The SG1526 is characterized
for operation over the full military ambient junction temperature range of
-55°C to +150°C. The SG2526 is characterized for operation from -25°C
to +150°C, and the SG3526 is characterized for operation from 0°C to
+125°C.
FEATURES
• 8 to 35 volt operation
• 5V reference trimmed to ±1%
• 1Hz to 350KHz oscillator range
• Dual 100mA source/sink outputs
• Digital current limiting
• Double pulse suppression
• Programmable deadtime
• Undervoltage lockout
• Single pulse metering
• Programmable soft-start
• Wide current limit common mode range
• TTL/CMOS compatible logic ports
• Symmetry correction capability
• Guaranteed 6 unit synchronization
HIGH RELIABILITY FEATURES - SG1526
♦ Available to MIL-STD-883B and DESC SMD
♦ Radiation data available
♦ LMI level "S"processing available
BLOCK DIAGRAM
+V_IN
GROUND
R_D
R_T
C
T
RESET
C_SOFTSTART
COMPENSATION
+ ERROR
— ERROR
+ C.S.
— C.S.
4/90 Rev 1.1 2/94
Copyright © 1994
V_REF
Reference
Regulator
Undervoltage
Lockout
Oscillator
To Internal ^SYNC
Circuitry
Soft
Start
+V_IN
Amp
S
S
Q
D
Q
RQ
MEMORY
F/F
METERING
F/F
Q
T
Q
TOGGLE
F/F
SHUTDOWN
1
+V_C
OUTPUT A
OUTPUT B
LINFINITY Microelectronics Inc.
11861 Western Avenue ∞ Garden Grove, CA 92841
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