The UCC3813-x family of high-speed, low-power integrated circuits contain all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count.

These devices have the same pin configuration as the UC384x family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input.

The UCC3813-x family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Lower reference parts such as the UCC3813-3 and UCC38135 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 and UCC3813-4 make these ideal choices for use in off-line power supplies.

The UCC2813-x series is specified for operation from –40°C to +85°C and the UCC3813-x series is specified for operation from 0°C to 70°C.

• 100-µA Typical Starting Supply Current
• 500-µA Typical Operating Supply Current
• Operation to 1 MHz
• Internal Soft Start
• Internal Fault Soft Start
• Internal Leading-Edge Blanking of the Current-Sense Signal
• 1-A Totem-Pole Output
• 70-ns Typical Response from Current-Sense to Gate-Drive Output
• 1.5% Tolerance Voltage Reference
• Same Pinout as UCC3802, UC3842, and UC3842A