Significantly reduce charge times in USB AC/DC wall chargers

Dialog Semiconductor have claimed that their iW1680 is the world’s first AC/DC rapid charge controller compatible with MediaTek’s Pump Express fast charge protocol. MediaTek’s proprietary protocol for fast charging mobile devices, including feature phones, smartphones and media tablets, Pump Express is up to 45% faster than conventional chargers.

Conventional USB chargers provide a fixed 5V supply that requires a buck converter inside the handset to convert this down to the required output voltage. With the iW1680, Dialog’s built-in, intelligent rapid charge digital algorithm communicates with MediaTek Pump Express-compatible phones and dynamically scales the output voltage of the wall charger to deliver the optimised level required by the phone at any given time. Eliminating the need for an input buck converter in the phone, this lowers the overall system cost and reduces charge times by enabling more efficient power transfer to the phone battery. Further reducing costs, the iW1680 embeds sophisticated digital analysis on the primary side of the isolated power supply within the charger. This also allows voltage scaling without the need for any intelligence on the secondary side.

Supporting power adapters up to 7.5W, the rapid charge AC/DC controller provides high active average efficiency and low no-load power consumption of less than 30mW. The iW1680 easily and efficiently drives low-cost bipolar junction transistor switches to further drive down BOM costs and reduce electromagnetic interference. Additionally, the device offers protection features including built-in output short-circuit, and output overvoltage, output over-current and over-temperature protection.

Mark Tyndall, Senior Vice President, Corporate Development & Strategy, GM Power Conversion Business Group, Dialog Semiconductor, commented: “Reducing charge time is one of the most compelling trends in smartphones, especially with the rapid and endless surge in ever more power-hungry applications. Working closely with MediaTek, we are delighted to introduce the first Pump Express-compatible AC/DC controller and bring our complementary rapid charge technologies to the China market quickly and cost effectively.”

Supplied in a 6-pin SOT23 package, Dialog's iW1680 rapid charge AC/DC controller is available now. The company is currently featuring its rapid charge AC/DC technology at Stand 7C05 in Hall 7 at Mobile World Congress in Barcelona, Spain.