UCC2895

application INFO available BiCMOS Advanced Phase Shift PWM Controller UCC1895 UCC2895 UCC3895 FEATURES Programmable Output Turn-on Delay Adaptive Delay Set Bidirectional Oscillator Synchronization Capability for Voltage Mode or Current Mode Control Programmable Soft Start/Soft Stop and Chip Disable via a Single Pin 0% to 100% Duty Cycle Control 7MHz Error Amplifier Operation to 1MHz Low Active Current Consumption (5mA Typical @ 500kHz) Very Low Current Consumption During Undervoltage Lock-out (150µA typical) DESCRIPTION The UCC3895 is a phase shift PWM controller that implements control of a full-bridge power stage by phase shifting the switching of one half-bridge with respect to the other. It allows constant frequency pulse-width modulation in conjunction with resonant zero-voltage switching to provide high efficiency at high frequencies. The part can be used either as a voltage mode or current mode controller. While the UCC3895 maintains the functionality of the UC3875/6/7/8 family and UC3879, it improves on that controller family with additional features such as enhanced control logic, adaptive delay set, and shutdown capability. Since it is built in BCDMOS, it operates with dramatically less supply current than it’s bipolar counterparts. The UCC3895 can operate with a maximum clock frequency of 1MHz. The UCC3895 and UCC2895 are offered in the 20 pin SOIC (DW) package, 20 pin PDIP (N) package, 20 pin TSSOP (PW) package, and 20 pin PLCC (Q). The UCC1...