SG3526 Datasheet, PDF (1/10 Pages) Motorola, Inc – PULSE WIDTH MODULATION CONTROL CIRCUIT

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SG3526
Pulse Width Modulation
Control Circuit
The SG3526 is a high performance pulse width modulator integrated
circuit intended for fixed frequency switching regulators and other power
control applications.
Functions included in this IC are a temperature compensated voltage
reference, sawtooth oscillator, error amplifier, pulse width modulator, pulse
metering and steering logic, and two high current totem pole outputs ideally
suited for driving the capacitance of power FETs at high speeds.
Additional protective features include soft start and undervoltage lockout,
digital current limiting, double pulse inhibit, adjustable dead time and a data
latch for single pulse metering. All digital control ports are TTL and B–series
CMOS compatible. Active low logic design allows easy wired–OR
connections for maximum flexibility. The versatility of this device enables
implementation in single–ended or push–pull switching regulators that are
transformerless or transformer coupled. The SG3526 is specified over a
junction temperature range of 0° to +125°C.
• 8.0 V to 35 V Operation
• 5.0 V ±1% Trimmed Reference
• 1.0 Hz to 400 kHz Oscillator Range
• Dual Source/Sink Current Outputs: ±100 mA
• Digital Current Limiting
• Programmable Dead Time
• Undervoltage Lockout
• Single Pulse Metering
• Programmable Soft–Start
• Wide Current Limit Common Mode Range
• Guaranteed 6 Unit Synchronization
Representative Block Diagram
Vref ¹⁸
VCC
17 Reference
Regulator
Ground ¹⁵
Sync
RDeadtime
RT
CT
12
11
9
10
Oscillator
Reset ⁵
CSoft–Start ⁴
Soft
Start
Compensation ³
VCC
+Error
–Error
1
Amp
2
+
–
+C.S. ⁷ +
6
–C.S.
–
Shutdown ⁸
Under–
Voltage
Lockout
To Internal
Circuitry
Toggle
Memory _F/F
F/F
Q
S
T
–
SQ _{R Q}
Q
+
DQ
Metering
F/F
14
VC
13
Output
A
16
Output
B
PULSE WIDTH MODULATION
CONTROL CIRCUIT
SEMICONDUCTOR
TECHNICAL DATA
18
1
N SUFFIX
PLASTIC PACKAGE
CASE 707
PIN CONNECTIONS
+Error 1
–Error 2
Compensation 3
CSoft–Start 4
Reset 5
–CS 6
+CS 7
Shutdown 8
RT 9
18 Vref
17 VCC
16 Output B
15 Ground
14 VC
13 Output A
12 Sync
11 RDeadtime
10 CT
(Top View)
ORDERING INFORMATION
Device
Operating
Temperature Range
Package
SG3526N TJ = 0° to +125°C Plastic DIP
MOTOROLA ANALOG IC DEVICE DATA
© Motorola, Inc. 1996
Rev 2
1