This datasheet provides detailed information on the UC1842/3/4/5 series current mode PWM controllers. This series of controllers features low start-up current (less than 1 mA), automatic feed forward compensation, pulse-by-pulse current limiting, enhanced load response characteristics, under-voltage lockout with hysteresis, double pulse suppression and high current totem pole output stage.
The UC1842/3/4/5 family provides off‑line and DC‑to‑DC converters with current‑mode control, low start‑up current, and a range of protection features. The device includes an internally trimmed band‑gap reference, under‑voltage lockout, and a high‑current totem‑pole output stage suitable for driving N‑channel MOSFETs.
The datasheet details absolute maximum ratings, electrical characteristics, oscillator design, shutdown techniques, and mechanical packaging information for the UC1842, UC2842, and UC3842 series. It also lists orderable device status and package options.
| Start‑up current | <1 mA |
|---|---|
| Operating supply voltage (VCC) | 12 V – 25 V |
| Output current sink capability | ±1 A |
The start‑up current is less than 1 mA.
UVLO turns on at 16 V and turns off at 10 V.
The UC1842 can operate with duty cycles approaching 100 %.