GENERAL DESCRIPTION
The AS1322A and the AS1322B are synchronous, fixed frequency, very high-efficiency DC-DC boost converters capable of supplying 3.3V at 150mA from a single AA-supply. Compact size and minimum external parts requirements make these devices perfect for modern portable devices. High-speed switching frequency (1.2MHz) and internally compensated PWM current mode design provide highly-reliable DCDC conversion, especially when driving white LEDs. The converters are available as the standard products listed in Table 1. Table 1. Standard Products Model Light Load Switching AS1322A Automatic Powersave Operation AS1322B Continuous Switching The devices contain two internal MOSFET switches: one NMOS switch and one PMOS synchronous rectifier. Anti-ringing control circuitry reduces EMI by damping the inductor in discontinuous mode, and the devices exhibit extremely low quiescent current (< 1µA) in shutdown. In shutdown mode the battery is connected to the output and VOUT is held at approximately VIN - 0.6V.
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