SG3526 Motorola Inc, SG3526 Datasheet - Page 7

• Manufacturer Part Number: SG3526
• Description: PULSE WIDTH MODULATION CONTROL CIRCUIT
• Manufacturer: Motorola Inc

+ Error
– Error
Reset
V CC
MOTOROLA ANALOG IC DEVICE DATA
Gnd
* May be required with some types of transistors
1
2
5
Figure 14. Oscillator Connections
R D
Figure 12. Extending Reference
Figure 16. Soft–Start Circuity
Output Current Capability
27
Q3
11
+
–
Error
Amp
9
C *
17
R T
SG3526
Undervoltage
Lockout
Reference
Regulator
To
10
Q1
15
100
A
C T
V ref
18
12
C Soft–Start
Ramp
Q2
APPLICATIONS INFORMATION
+
Sync
10 F
V ref
–
+
PWM
SG3526
V ref
Gnd
V out = V ref
R 3
R 2
Figure 13. Error Amplifier Connections
I (max) =
8
Figure 17. Driving VMOS Power FETs
Figure 15. Foldback Current Limiting
The totem pole output drivers of the SG3526 are ideally
suited for driving the input capacitance of power FETs at
high speeds.
R 1 + R 2
R2
+12V
R 1
1
2
+
–
0.1 V +
SG3526
Output Filter
Positive
Output
Voltage
Gnd
V C
R 3 =
–
+
14
R S
R1 + R2
V out R 1
6
7
A
B
Gnd
13
16
R 1 + R 2
V ref
R 1 R 2
Gnd
R 2
R 3
R 1
R 2
R S
V out = V ref
I SC =
R 1
0.1 V
1
2
R S
V out
+
–
R 1
R 2
+
–
Negative
Output
Voltage
7