Driver IC optimises Class-D audio amps with GaN output FETs

October 18, 2017 // By Graham Prophet
Peregrine Semiconductor – part of Murata – pioneer of silicon-on-insulator technology for RF circuitry (RF SOI) has added a high-speed FET driver to its range. The UltraCMOS PE29102 offers switching frequency up to 40 MHz to realise maximum performance and switching-speed advantages from the use of GaN transistors.

In class-D audio amplifiers, this high-speed FET driver enables low jitter switching with GaN technology to deliver superior audio performance.

 

The PE29102 is intended for either half-bridge or full-bridge configurations. It integrates resistor-settable, internal dead-time control and its design is aimed at preserving the integrity of the incoming audio signal. When used in conjunction with GaN FETs, low dead times minimize crossover distortion in class-D applications. The PE29102’s phase-control pins enable the same part to be used for both phases in bridge-tied load (BTL) configurations—a technique used in audio amplifiers. It has an output source current of 2A and an output sink current of 4A. The PE29102 handles voltages up to 60V and supports a gate drive up to 6V.

Offered as a 2 x 1.6 mm flip-chip die, PE29102 volume-production parts, samples and evaluation kits are available now.

 

Peregrine adds; Audio systems are challenged to both minimize size and deliver exceptional audio quality to listeners, at lowest distortion. MOSFET components have parasitic diodes and gate capacitance that creates jitter and distortion in class-D audio systems, whereas GaN FETs have much smaller gate capacitance and lower parasitics. GaN transistors can beat MOSFET jitter performance by a factor of ten and deliver reduced distortion and smooth sound, the company asserts. GaN transistors need an optimized gate driver. The PE29102’s high switching speeds result in smaller peripheral components and enable innovative designs for applications such as class-D audio. A video clip is here.

To showcase the GaN-enabling capabilities of this driver, Peregrine developed evaluation kits with two GaN transistor providers—GaN Systems and EPC.

 

Paul Wiener, vice president of strategic marketing at GaN power device maker GaN Systems comments, “Our customers have validated the improved sound quality with GaN-based circuits, and we see the pairing of Peregrine’s driver and GaN Systems’ transistors as the superior solution in applications such as class-D audio, bi-directional DC-DC, and push-pull DC-AC power supplies.”