IC manufacturers Texas Instruments

IC manufacturers (96)

Texas Instruments UCC28781-Q1 | Demoboard UCC28781EVM-053

UCC28781 Zero-Voltage-Switching Flyback Controller with Dedicated Synchronous Rectifier Gate-Drive

Overview

TopologyFlyback Converter
Input voltage90-264 V
Output 115 V

Description

The UCC28781 is a zero-voltage-switching (ZVS) controller which can be used at very high switching frequencies to minimize the size of the transformer and enable high power density. With direct synchronous rectifier (SR) control, the controller does not need a separate SR controller, as it can drive the SR FET directly to maximize efficiency and simplify design. (For isolated applications, an isolated gate-driver IC is required.)Using adaptive dead-time control for ZVS, switching losses and EMI are minimized. This design results in a controller with extremely high conversion efficiency across the entire operating range.The programmable adaptive burst mode (ABM) gives flexibility to control when the controller enters and exits standby mode to optimize standby power in light and no-load conditions. ABM also helps to reduce ripple and minimize audible noise.The controller offers multiple protection modes with automatic restart (retry) responses.

Features

  • Switching frequency: > 500 kHz
  • Enables peak efficiency > 93 %
  • Enables < 45 mW stand-by power
  • Adaptive control for zero-voltage-switching (ZVS) and dead-time optimization
  • EMI frequency-dithering without trade-offs on transient response or audible noise
  • Programmable adaptive burst mode (ABM) with internal compensation
  • X-capacitor discharge capability
  • Over-temperature, overvoltage, output shortcircuit, overcurrent, over-power, and pin-fault protections
  • Auto-recovery fault-responses
  • 4 mm × 4 mm, 24-pin, QFN package

Typical applications

  • Industrial AC-DC
  • Merchant Network and Server PSU
  • Appliances Battery Charger, Merchant Battery Charger
  • Soundbar, Smart Speaker

Products

Order Code Data­sheet Simu­lation Downloads Product seriesApplicationCVR
(V (AC))
Safety ClassdV/dt
(V/µs)
DF @ 1 kHz
(%)
RISOOperating TemperaturePitch
(mm)
L
(mm)
W
(mm)
H
(mm)
PackagingL
(µH)
IR
(A)
RDC max.
(Ω)
Samples
890324024003SPEC
8 files WCAP-FTX2 Film Capacitors Across the mains330 nF 275 X2 260 0.130 GΩ -40 °C up to +105 °C 12.5 15 8.5 14 Bulk
7447052SPEC
6 files WE-FI Leaded Toroidal Line Choke 10 6.6 32 2.6 0.045
Order Code Data­sheet Simu­lation
890324024003SPEC
7447052SPEC
Samples
Order Code Data­sheet Simu­lation Downloads Product seriesApplicationCVR
(V (AC))
Safety ClassdV/dt
(V/µs)
DF @ 1 kHz
(%)
RISOOperating TemperaturePitch
(mm)
L
(mm)
W
(mm)
H
(mm)
PackagingL
(µH)
IR
(A)
RDC max.
(Ω)
Samples