1 Features

? Integrated 700V GaN with 170mΩ Rds(on)

? Dynamic QR/DCM/CCM modes of operation

? Support up to 500kHz switching frequency

? Enable low BoM cost by integration

– Remove auxiliary winding with self bias

– Integrated input/output voltage sensing

– Integrated current sense

– Integrated HV startup

– Integrated X-cap discharge

? High efficiency and low EMI performance

– Ultra-low standby power: <30mW

– Frequency foldback and burst mode

– Valley locking

– Frequency dithering

– Switching slew rate control

? Comprehensive protection features

– Over Temperature Protection

– Over Voltage Protection

– Short Circuit Protection

– Cycle-by-cycle current limit

– Two-Level Over Power Protection with LPS

– Brown-in/out Protection

– Open feedback protection

? Flexible configurability via external resistors

– X-cap discharge and CCM mode disable

– Selectable switching slew rate

– Multiple clamping frequency settings

– Fault latch or auto-restart

– Max/min peak current ratio

– Dithering amplitude

2 Applications

? USB-PD Adapter for portable electronics

? USB wall outlets and docking stations

? Industrial DIN Rail power supplies

? Server Aux Power Supplies

3 Description

UCG28826 is a high frequency, quasi-resonant

flyback converter with built-in 170mΩ GaN high

electron mobility transistor (HEMT) to convert AC to

DC for up to 65W power converters. It is best suited

for high power density applications such as cell phone

fast chargers and laptop adapters. The key feature

of this device is the self-bias and auxless sensing

scheme which completely eliminates the need of the

auxiliary winding and simplifies the system design

with higher efficiency.

This device also features intelligent mode transition

(CCM/QR/DCM) to enable high efficiency across

wide power range and <30mW standby power

consumption. In addition, UCG28826 includes a full

list of protections such as brown-in/out protection,

SCP, OVP, OLP, OFB and OTP. The cycle-by-cycle

current limit ensures fast response to the fault

conditions to safeguard the system and improve the

reliability. The Input feedforward and output voltage

based OLP correction are implemented to meet

LPS requirements. Furthermore, the UCG28826 has

dedicated configuration pins to offer more flexibility.

Only resistors are needed to tune certain parameters

for each system, enabling a platform design with a

single device.