Texas Instruments (TI) introduced on Friday, March 13, a 80-V / 10-A integrated Gallium Nitride (GaN) FET power-stage prototype, which consists of a high-frequency driver and two GaN FETs in a half-bridge configuration – all in a quad flat no-leads (QFN) package. TI does not introduce a GaN switch – instead the company relies on Enhancement-Mode GaN switches from Efficient Power Conversion (www.epc-co.com) and its already supplied GaN drivers.

According to TI Enhancement-Mode GaN power FETs can provide significant power density benefits over Silicon MOSFETs in power converters but pose new challenges for designers. TI solves the challenges of driving GaN power FETs with a family of drivers – UCC27611, a 4 A/6 A high-speed, optimized single gate driver, LM5114, a 7.6 A single low-side driver with independent source and sink outputs – and the LM5113, a 100 V integrated half-bridge driver for GaN power FETs. Compared to discrete implementations, these drivers provide significant PCB area savings to achieve high power density and efficiency while simplifying the task of driving GaN FETs reliably.

The new LMG5200 GaN FET power stage will help accelerate market adoption of GaN power-conversion solutions that provide increased power density and efficiency in space-constrained, high-frequency industrial and telecom applications. The power stage will be highlighted as part of a 48-V digital power demonstration at the Applied Power Electronics Conference (APEC), in Charlotte, North Carolina, March 16-18 (booth No. 1001).

Typically, designers who use GaN FETs that switch at high frequencies must be careful with board layout to avoid ringing and electromagnetic interference (EMI). The dual 80-V power stage prototype eases this issue while increasing power-stage efficiency by reducing packaging parasitic inductance in the critical gate-drive loop. The LMG5200 features multichip packaging and is optimized to support power-conversion topologies with switching frequencies up to 5 MHz.

Also the 6-mm x 8-mm QFN package requires no underfill, which significantly simplifies manufacturing. The reduced footprint solidifies the value of GaN technology and will help increase adoption of GaN power designs in many new applications, ranging from high-frequency wireless charging applications to 48-V telecom and industrial designs.

For quick evaluation the LMG5200 EVM board is a small easy to use power stage with an external PWM signal. The EVM is suitable for evaluating the performance of LMG5200 power stage in many different DC/DC converter topologies. It can be used to estimate the performance of LMG5200 to measure efficiency. The module is capable of delivering a maximum of 10 A of current however adequate thermal management (forced air, running at low frequency etc) should be followed to ensure that the temperature is not exceeded. The EVM is not suitable for transient measurements as it is an open loop board. In addition to ordering the EVM, designers can get started faster using PSpice and TINA-TI models for the LMG5200 to simulate the performance and switching frequency advantages of this technology. Prototype samples of the GaN power stage are available to purchase in the TI Store. The LMG5200 is priced at $50 each with a maximum purchase of 10 units. The LMG5200 EVM is available for $299. More in the upcoming PEE issue.