650V GaN power ICs for power adapters have driver and protection

Texas Instruments has announced a series of GaN power switches for ac-dc and dc-dc converters that include an integrated driver, protection and current sense emulation.

The parts, called LMG362x, differ in the size of the GaN hemt switch included. They are:

LMG3622 650V120mΩ 8.5A
LMG3624 650V 170mΩ 6A
LMG3626 650V 270mΩ 3.6A

“Using the LMG3622 only requires setting the desired turn-on slew rate with a programming resistor and
calculating the current sense resistor,” according to the company. Using the ICs “designers can reach up to 94% system efficiency for <75W ac-dc applications, or above 95% system efficiency for >75W ac-dc applications”.

Features include a bottom-side cooled 8 x 5.3mm QFN package, cycle-by-cycle over-current protection, enable pin, over-temperature protection and slew rate control. For the …24 and …22, TI adds USB C/PD compatibility to this list.

The devices are optimised, said TI, for quasi-resonant fly-back, asymmetrical half-bridge fly-back, inductor-inductor-converter (LLC), totem-pole power factor correction and active clamp fly-back topologies.

There is an evaluation module for each IC, all implementing a 65W quasi-resonant fly-back converter with USB Type-C PD: LMG3622EVM-082 (left), LMG3624EVM-081 and LMG3626EVM-074.

For example, …2EVM-082 meets CoC Tier 2 and DoE Level 6 efficiency requirements and works from inputs across 90 to 265Vrms to outputs of 20Vdc at 3.25A, or 5, 9 or 15Vdc at 3A.

If current sensing is not required, LMG3612 and LMG3616 are similar pad-for-pad devices.

Find the 120mΩ 8.5A LMG3622 on this product page and its evaluation board here