Product Summary

The KA3843 is a fixed frequency current-mode PWM controller. The KA3843 is specially designed for Off - Line and DC-to-DC converter applications with minimum external components. The device features 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. It has UVLO thresholds of 16V (on) and 10V (off). The KA3843 is 8.5V (on) and 7.9V (off).

Parametrics

KA3843 absolute maximum ratings: (1)Supply Voltage, VCC: 30 V; (2)Output Current, IO: ±1 A; (3)Analog Inputs (Pin 2.3), V(ANA): -0.3 to 6.3 V; (4)Error Amp Output Sink Current, ISINK (E.A): 10 mA; (5)Power Dissipation at TA≤25℃ (8DIP), PD: 1200 mW; (6)Power Dissipation at TA≤25℃ (14SOP), PD: 680 mW; (7)Storage Temperature Range, TSTG -65 to +150℃; (8)Lead Temperature (Soldering, 10sec), TLEAD: +300℃.

Features

KA3843 features: (1)Low Start up Current; (2)Maximum Duty Clamp; (3)UVLO With Hysteresis; (4)Operating Frequency up to 500KHz.

Diagrams

KA3843 circuit diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)		 Quantity
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KA3843ACDSTF
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Data Sheet
0-1: $0.52
1-25: $0.46
25-100: $0.35
100-250: $0.31
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Fairchild Semiconductor
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Data Sheet
Negotiable 
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Data Sheet
Negotiable 
KA3843AM
KA3843AM
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Data Sheet
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Data Sheet
Negotiable 
KA3843AC
KA3843AC
Other

Data Sheet
Negotiable