SG3526_06 Datasheet, PDF (1/9 Pages) ON Semiconductor – Pulse Width Modulation Control Circuit

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
18
1
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MARKING
DIAGRAM
18
PDIP−18
N SUFFIX
CASE 707
SG3526N
AWLYYWW
1
A = Assembly Location
WL = Wafer Lot
YY = Year
WW = Work Week
PIN CONNECTIONS
+Error 1
−Error 2
Compensation 3
C_{Soft−Start} 4
Reset 5
−CS 6
+CS 7
18 V_ref
17 V_CC
16 Output B
15 Ground
14 V_C
13 Output A
12 Sync
V_ref ¹⁸
V_CC
17 Reference
Regulator
Ground ¹⁵
Sync
R_Deadtime
R_T
C_T
12
11
9
10
Oscillator
Under−
Voltage
Lockout
To Internal
Circuitry
Reset ⁵
C_{Soft−Start} ⁴
Soft
Start
Compensation ³
V_CC
+Error
−Error
1
2
+
−
−
+
100 mV Amp
7
+C.S.
−C.S.
6
+
−
Shutdown ⁸
Memory
F/F
S
SQ _{R Q}
RQ
Metering
F/F
Toggle
F/F
Q
T
Q
Figure 1. Representative Block Diagram
Shutdown 8
R_T 9
11 R_Deadtime
10 C_T
14
V_C
13
Output
A
(Top View)
ORDERING INFORMATION
Device
Package
Shipping
SG3526N
PDIP−18
20 Units/Rail
16
Output
B
© Semiconductor Components Industries, LLC, 2006
1
July, 2006 − Rev. 4
Publication Order Number:
SG3526/D