AN727

The Si9167 is a high-frequency synchronous dc-to-dc switching buck regulator, with an operating range suitable for two-cell Li+ battery-powered applications. Capable of operation up to 2 MHz, the Si9167 can be used to supply power amplifiers and to power up baseband circuits in satellite phones. Its high operating frequency reduces the size of inductor and capacitor components, while its low on-resistance internal driver ensures maximum power conversion efficiency. Additional features include an integrated input undervoltage lockout, power on reset, integrated soft start, light load pulse skipping mode selection, synchronization, clock output for master-slave configuration of multiple regulators, uncommitted power-good comparator, and over temperature protection. An output power in excess of 2 W at 3.6 VO is possible in 0.3 square inches.