Tiny battery chargers deliver 50% greater power density

By Gina Roos, editor-in-chief

Texas Instruments (TI) has claimed the smallest buck-boost battery charger ICs with the introduction of the BQ25790 and BQ25792 devices. These buck-boost battery chargers integrate power-path management for maximum power density and universal and fast charging at up to 97% efficiency. They also provide 10× lower quiescent current through USB Type-C and USB Power Delivery (PD) ports in small personal electronics, portable medical devices, and building automation applications.

Touted as the industry’s first multi-cell buck-boost battery chargers with less than 1 µA of quiescent current, the BQ25790 and BQ25792 deliver at least 5× longer shelf life than competitive devices through a dual ship mode and shutdown function that delivers up to 10× lower quiescent current. Combined with an extremely low battery FET resistance of 8 mΩ, engineers can further maximize battery runtime for applications that require long periods of operation, said TI.

Offering 50% greater power density and 3× faster charging for USB Type-C, USB PC, and wireless dual-input charging, the BQ25790 and BQ25792 offer the flexibility to charge batteries with one to four cells in a series and up to 5 A of charging current across the full input-voltage range (3.6 V to 24 V) for USB Type-C and USB PD applications. The chargers’ integrated dual-input selector supports multiple power sources, including wireless, USB, barrel jack, and solar charging while delivering the industry’s fastest charge — 97% efficiency at 30 W, according to TI.

The chargers deliver 155 mW/mm² (100 W/in.² ) of power — up to 2× more than competitive devices, said TI, which helps engineers reduce solution size and bill of materials (BOM). In addition, the buck-boost chargers are claimed to be the industry’s first to fully integrate the following components: switching MOSFETs, a battery FET, current-sensing circuits and a dual-input selector.

The BQ25790 (2.9 × 3.3-mm, 56-pin WCSP) and the BQ25792 (4 × 4-mm, 29-pin QFN) chargers are available from TI and authorized distributors. Pricing starts at $2.99 and $2.99, respectively, in quantities of 1,000. The BQ25790EVM evaluation module is available on TI.com for $149.