Texas Instruments Releases New UCC3895 Unitrode PWM Controller
Texas Instruments (Dallas, TX) recently announced a new Unitrode PWM controller, the UCC3895. According to the company, the device is designed to improve performance and lower the power consumption of high-power supply applications above 500W. The device also features the company's BiCMOS technology.
Texas Instruments claims that the UCC3895 operates at a constant switching frequency and shifts the gate-drive phase of one-half of a full-bridge power stage with respect to the other to achieve PWM control. The device also features programmable turn-on delay circuitry and broadband control features to enable zero-voltage switching in high-frequency, high-power converters. The UCC3895 also includes what Texas Instruments claims is an innovative, programmable adaptive delay set. This function is designed to modulate the delay times between the outputs inversely with the load current, facilitating zero-voltage switching of the power devices over a wide range of loads.
The UCC3895 contains four low-current, high-speed outputs to interface with external FET gate-drive circuitry, giving designers the flexibility to optimize gate-drive location and current level. Additional features include enhanced logic for voltage- or current-mode control, soft-start and shutdown capability, and a 1MHz oscillator with bi-directional synchronization.
"Unitrode power-supply products from Texas Instruments continue to enable designers of advanced power-supply applications to maximize their system's performance," said Rich Valley, business manager for Texas Instrument's power-supply control products. "By combining advanced-process technology with the latest in control methods, we expect the UCC3895 to become a new standard for use in high-density applications above 500W."
The UCC3895 is available in either a 20-pin, wide-body, SOIC package; a 20-pin, plastic, PDIP; a 20-pin PLCC; or a 20-pin DIP. In quantities of 1,000, suggested retail pricing ranges from $5.78 to $5.95.
