AS1322
Low Voltage, 1.2 MHz, Micropower, DC-DC Step-Up Converter - TSOT23-6
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 DC-DC conversion, especially when driving white LEDs.
The converters are available as the 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.
The AS1322 is available in a 6-pin TSOT-23 package.
Key Features
- 95% Efficiency
- Single-Cell Operation
- Delivers 150mA @ 3.3V (from Single AA Cell)
- Delivers 500mA @ 3.3V (from Two AA Cells)
- Low Start-Up Voltage: 0.85V
- High-Speed Fixed-Frequency: 1.2MHz
- Internal PMOS Synchronous Rectifier
- Automatic Powersave Operation (AS1322A)
- Continuous Switching at Light Loads (AS1322B)
- Anti-Ringing Control Minimizes EMI
- Logic Controlled Shutdown (< 1μA)
- Output Range: 2.5 to 5.0V
- 6-pin TSOT-23 Package
Applications
The AS1322 is ideal for low-power applications where ultra-small size is critical as in medical diagnostic equipment, hand-held instruments, pagers, digital cameras, remote wireless transmitters, MP3 players, LCD bias supplies, cordless phones, GPS receivers, and PC cards.
