UCC3810

Features:

· Single Oscillator Synchronizes Two PWMs
· 150 A Startup Supply Current
· 2mA Operating Supply Current
· Operation to 1MHz
· Internal Soft Start
· Full-Cycle Fault Restart
· Internal Leading Edge Blanking of the Current Sense Signal
· 1 Amp Totem Pole Outputs
· 75ns Typical Response from Current Sense to Output
· 1.5% Tolerance Voltage Reference


Pinout




Specifications

V_CC Voltage (Note 3) . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 11V
V_CC Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mA
OUT1, OUT2 Current, Peak, 5% Duty Cycle. . . . . . . . . .  . . ±1A
OUT1, OUT2 Energy (Capacitive Load) . . . . . . . . . . .  . . . . 20J
Analog Inputs (FB1, FB2, CS1, CS2, SYNC). . . . .. 0.3V to 6.3V
Operating Junction Temperature . . . . . . . . . . . . . . . . . . +150
Storage Temperature Range . . . . . . . . . . . . . 65 to +150
Lead Temperature (Soldering, 10 seconds) . . . . . . .  .. . . 300


Description

The UCC3810 is a high-speed BiCMOS integrated circuit which implements two synchronized pulse width modulators for use in off-line and
DC-to-DC power supplies.

The UCC3810 provides perfect synchronization between two PWMs by using the same oscillator. The oscillator's sawtooth waveform can be used for slope compensation if required.

Using a toggle flip flop to alternate between modulators, the UCC3810 ensures that one PWM will not slave, interfere, or otherwise affect the other PWM. This toggle flip flop also ensures that each PWM will be limited to 50% maximum duty cycle, insuring adequate off-time to reset magnetic elements.

This IC UCC3810 contains many of the same elements of the UC3842 current mode controller family, combined with the enhancements of the UCC3802. This minimizes power supply parts count. Enhancements include leading edge blanking of the current sense signals, full cycle fault restart, CMOS output drivers, and outputs which remain low even when the supply voltage is removed.