A6983 Buck Regulators

STMicroelectronics' A6983 is an easy-to-use synchronous monolithic step-down regulator capable of delivering up to 3 A_DC to the load. The wide input voltage range makes the device suitable for a broad range of applications. The A6983 is based on a peak current mode architecture and is packaged in a QFN16 (3 mm x 3 mm) with internal compensation, thus minimizing design complexity and size. The low consumption mode (LCM) is designed for applications active during car parking, so it maximizes the efficiency at the light load with the controlled output voltage ripple. The low noise mode (LNM) makes the switching frequency constant and minimizes the output voltage ripple overload current range, meeting the low noise application specification like car audio.

The A6983 allows the switching frequency to be selected in the 200 kHz to 2.3 MHz range with an optional spread spectrum for improved EMC. The EN pin provides enable/disable functionality. The typical shutdown current is 2 μA when disabled. The device is enabled as soon as the EN pin is pulled up and the internal 1.3 ms soft-start takes place. The A6983 features a Power Good open collector that monitors the FB voltage. Pulse-by-pulse current sensing on both power elements implements effective constant current protection, and thermal shutdown prevents thermal runaway.