21 June 2022
Qorvo introduces GaN PA biasing reference design
Qorvo Inc of Greensboro, NC, USA (which provides core technologies and RF solutions for mobile, infrastructure and defense applications) has announced the availability of the ACT41000-104-REF1, a gallium nitride (GaN) power amplifier (PA) biasing reference design that enhances the design and testing of the firm’s GaN PAs.
Since GaN devices are depletion-mode FETs that require a negative gate voltage during operation, in systems using GaN PAs a specific bias sequencing is required: a negative gate voltage must be applied before increasing the drain bias voltage to protect the device from damage.
The ACT41000-104-REF1 provides built-in configurability that enables it to bias a variety of GaN PAs and auto-calibrate the system. It integrates the power MOSFETs and current digital-to-analog converter to allow the device to precisely detect the PA quiescent drain current. The design uses power management to simplify the GaN biasing procedure.
The ACT41000 can operate from an input voltage of 4.5-40V, which enables it to generate a regulated adjustable output voltage up to 24V at 4A, in small steps of 12.5mV. It comes with an evaluation platform and GUI, allowing users to adjust the output drain voltage, quiescent and maximum drain current, PA device current and voltage protection, switching frequency and other features to optimize GaN PA performance.
This procedure takes place every time a user powers up the system, providing auto-tuning under conditions such as aging or temperature fluctuations, hence making testing easier and more automated. The ACT41000’s built-in configurability allows it to bias a variety of Qorvo GaN PAs across many markets, including satellite communications, 5G, and radar.
“Qorvo is dedicated to simplifying the design and testing of real-world solutions for our customers and suppliers,” says David Briggs, senior director of Qorvo’s Programmable Power Management Products. “This newest integration of Qorvo’s power products into our GaN portfolio is just the tip of the iceberg of our planned portfolio expansion.”