140-W GaN charger shrinks in size

GaN Systems has released a new turnkey 140-W AC/DC charger reference design with a USB PD3.1, single-port Type-C output. The GaN charger design is 40% lighter and 50% smaller compared to silicon-based chargers, and it provides an ultra-high power density of 23 W/in³, said the company.

(Source: GaN Systems)

The new reference design joins GaN Systems’ portfolio of 65-W, 100-W, and 250-W turnkey charger solutions for the consumer electronics market. Applications include smartphones, PCs, and other personal devices.

The 140-W GaN charger is a complete turnkey solution with complete documentation. The fast charger offers a high-frequency, two-stage power topology with a bridgeless totem pole PFC and dual-switch QR flyback topology. It offers a higher than 94% peak efficiency and an input voltage range of 90 V to 64 VAC. Standby power is <120 mW. System protection includes OVP, OCP, and SCP.

The reference design includes two power conversion stages – a bridgeless totem pole power factor correction (BTP-PFC) and dual switch quasi-resonant (DS-QR) flyback – as shown in the block diagram. Click for a larger image. (Source: GaN Systems)

In addition to supporting the USB PD3.1 fast charging protocol, other protocol support includes PPS, QC5.0, AFC, and UFCS. It passes EN55032 Class B for conducted and radiated EMI and meets the IEC 62368-1 touch temperature requirement.

The design uses the company’s GS-065-011-1-L 650-V enhancement-mode GaN-on-silicon power transistor in a 5 × 6 mm PDFN package with bottom-side cooling. Key specs include an R_DS(on) of 150 mΩ, high switching frequency of >1 MHz, and gate drive requirements from 0 V to 6 V. Other features include fast and controllable fall and rise times, reverse conduction capability, and zero reverse recovery loss.

GaN transistors allow chargers to operate more efficiently with less power loss and heat, said the company. This enables the use of smaller components packaged much closer together for smaller charger designs with more power than larger models.