Hsinchu, Taiwan, March 1, 2022 – Weltrend Semiconductor (TWSE: 2436) today announced the availability of GaN-based power adapter reference design with WT7162Rx series high frequency multi-mode flyback PWM controllers. The reference design enables fast design of ultra-small form factor USB PD power adapters.

The WT7162Rx series chipsets are highly integrated and high frequency flyback PWM controllers capable of multi-mode operations including quasi-resonant (QR) and discontinuous conduction mode (DCM) with valley switching. The chips improve the overall efficiency and optimize the product performance while greatly reduce component count and costs.

The controllers operate in QR switching mode during high output power and reduce switching frequency to support valley switching in DCM during medium/low output power, allowing the charger to achieve the optimal conversion efficiency over the full output power range.

For the safety protections of USB PD charger and power adapters, the WT7162Rx series chipsets provide comprehensive protection mechanisms such as X-capacitor discharge protection, AC mains under-voltage protection (BNI/BNO), output over-voltage protection (OVP), output short-circuit protection (SCP), internal over-temperature protection (OTP), output over-load protection (OLP) and etc. Moreover, adaptive over-power protection (OPP) and adaptive green mode for optimal efficiency are provided for wide output voltage application.

This series of control chips includes WT7162RH and WT7162RG. The WT7162RH is specially used for super junction MOSFET while WT7162RG provides a 6V clamped gate voltage for directly driving new-generation compound semiconductor gallium nitride (GaNFET) power switches.

The reference design is a 60W USB PD adapter (5V/3A; 9V/3A; 12V/3A; 20V/3A; PPS 3.3V~21V/3A). The design includes WT7162Rx PWM controller with ultra-high voltage (UHV) startup, WT7131A SR controller supporting CCM/DCM high frequency synchronous rectification, and WT6636F USB PD protocol controller, together with GaNFET power switch.

It achieves both high efficiency and small factor (L: 43mm/W: 43mm/H: 22mm), and passes the EMC/ESD/Surge test, while supporting USB PD 3.0 PPS and Qualcomm’s Quick Charge 4+ fast charge protocols. 

                                                                           Fig. Weltrend 60W ultra-small GaN-based USB PD adapter reference design

About Weltrend Semiconductor Inc.

Founded in 1989 in the "Silicon Valley of Taiwan", the Science-Based Industrial Park (SBIP) in Hsinchu, Weltrend Semiconductor, Inc. (TWSE: 2436) is a leading fabless semiconductor company, also known as IC design house, specializing in the planning, design, testing, application development and distribution of mixed-signal/digital IC products across multiple applications. For more information, please visit www.weltrend.com.