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.