Semiconductor
S3843P
Current Mode PWM Controller
Descriptions
The S3843 is fixed Current PWM controller for Off-line a...
Semiconductor
S3843P
Current Mode PWM Controller
Descriptions
The S3843 is fixed Current PWM controller for Off-line and DC-DC converter applications. The internal circuits feature a trimmed oscillator for precise duty cycle control, a temperature compensated reference, high gain error amplifier current sensing comparator, and a high current totempole output for driving a power
MOSFET. Protection circuitly includes built in under
voltage lockout and current limiting. S3843 have UVLO threshold of 8.4V(on) and 7.6V(off). S3843 can operate within 100% duty cycle.
Features
Optimized for off-line and DC to DC converters Low start up current < 1 mA Operating range up to 500 KHz Pulse-by-pulse current limiting Under
Voltage Lock Out with hysteresis
High current totempole output
Short shutdown delay time ; typical 100nsec
Ordering Information
Type NO. S3843P Marking S3843P Package Code DIP-8
Outline Dimensions
unit :
mm
PIN Connections
1. Output / Compensation 2.
Voltage feedback. Input 3. Current sense Input 4. Rt/Ct 5. GND 6. Output 7. Vcc 8. Vref
KSI-L007-000
1
S3843P
Absolute Maximum Ratings
Characteristic
Supply
Voltage Output Current Analog Inputs Error Amp. Output Sink current Power Dissipation
Ta=25°C
Symbol
Vcc Io Vi(ana) Isink(EA) Pd
Ratings
30 1 -0.3 to 6.3 10 1
Unit
V A V mA W
Electrical Characteristics
(Vcc=15V, Rt=10Kohm, Ct=3.3nF, Ta=0℃ to 70℃, Unless otherwise specified)
Characteristic
1. Reference Section
Output
Voltage Line Regulatio...