1 Features

1• Constant-Voltage (CV) and Constant-Current (CC)

Output Regulation Without Optical-Coupler

• ±5% Output Voltage Regulation Accuracy

• ±5% Output Current Regulation With AC Line and

Primary Inductance Tolerance Compensation

• 700-V Start-Up and Smart Power Management

Enables <30-mW Standby Power

• 115-kHz Maximum Switching Frequency Design

for High-Power Density

• Valley Switching and Frequency Dithering to Ease

EMI Compliance

• Thermal Shut Down

• Low Line and Output Over-Voltage Protection

2 Applications

• Home and Building Automation

• Power Metering Bias

• Bias Power for Smoke Alarm, Fire Alarm and

Thermostat

• Wall Adapters, Chargers for Mobile Phones

• Smart plug, IoT, MCU and WiFi Power

• Aux power for TV, Server, White Goods

• LED Lighting

3 Description

The UCC28910 and UCC28911 are high-voltage

flyback switchers that provide output voltage and

current regulation without the use of an optical

coupler. Both devices incorporate a 700-V power FET

and a controller that process operating information

from the flyback auxiliary winding and power FET to

provide a precise output voltage and current control.

The integrated high-voltage current source for startup

that is switched off during device operation, and the

controller current consumption is dynamically

adjusted with load. Both enable the very low stand-by

power consumption.

Control algorithms in the UCC28910 and UCC28911,

combining switching frequency and peak primary

current modulation, allow operating efficiencies to

meet or exceed applicable standards. Discontinuous

conduction mode (DCM) with valley switching is used

to reduce switching losses. Built-in protection features

help to keep secondary and primary component

stress levels in check across the operating range.

The frequency jitter helps to reduce EMI filter cost.