New Industry Products

GaN Power Integrated Circuit for Wireless Power Transfer

July 13, 2015 by Jeff Shepard

Efficient Power Conversion Corp. (EPC) announces the EPC2107 (100V) and EPC2108 (60V) eGaN® half-bridge power integrated circuits with integrated bootstrap FET, eliminating gate driver induced reverse recovery loses as well as the need for a high-side clamp. This is the first time that a bootstrap FET has been integrated in an eGaN power circuit.

Designed specifically for resonant wireless power transfer applications, these products enable rapid design of highly efficient end-user systems, setting the stage for mass adoption of wireless power transfer. In addition, these GaN power integrated circuits come in extremely small, chip-scale packages, reducing the size of the overall system. This new line of chips is lower in cost due to reduced overall component count – one GaN device versus three FETs.

The EPC2107 has a Vds of 100V, both the control FET and the sync FET have on-resistances of 240 mΩ, the bootstrap FET has an on-resistance of 2.1Ω, typical Qoss for the three FETs are, 800pC for the control FET, 1400pC for the syncFET, and 140pC for the bootstrap FET. The EPC2108 has a Vds of 60 V, both the control FET and the SyncFET has on-resistances of 150mΩ, the bootstrap FET has an on-resistance of 2.1Ω, typical Qoss for the three FETs are, 650pC for the control FET, 1000pC for the syncFET, and 100pC for the bootstrap FET.

Although there are several standards for wireless power transfer, the A4WP standard, Rezence, offers superior features and capabilities to end users – the consumer. For example, Rezence allows for spatial freedom when charging, eliminating the need for exact positioning of devices when charging. It also has an exceptional charging range, providing consumers with true ‘drop and go’ charging.

Additionally, the standard allows for charging multiple devices with different power requirements simultaneously. Another key feature is that Rezence compliant wireless power systems will charge devices in the presence of metallic objects such as keys, coins, and utensils, making it an ideal choice for automotive, retail, and household applications.

By integrating two eGaN® power FETs into an integrated power circuit, interconnect inductances and the interstitial space needed on the PCB are eliminated. Having this single integrated power component increases both efficiency (especially at higher frequencies) and power density, while reducing assembly costs to the wireless power system designer’s end product. These devices come in 1.35 mm x 1.35 mm chip-scale package for reduced size, improved switching speed, and thermal performance leading to increased power density.