■Overview
The AN8049SH is a three-channel PWM DC-DC converter control IC that features low-voltage operation.
This IC can form a power supply that provides two step up outputs and one step-down or polarity inverted output  with a minimal number of external components. The AN8049SH features the ability to operate from a supply voltage as low as 1.8 V, and thus can be operated from two dry-batteries.

■Features
•Wide operating supply voltage range: 1.8 V to 14 V
•High-precision reference voltage circuit
  —VREFpin voltage: ±1%
  — Error amplifier: ±1.5%
•Surface mounting package for miniaturized and thinner power supplies Package: SSOP-24D
  0.5-mm lead pitch
  7.8 mm ×6.8 mm ×t1.9 mm
•Supports control over a wide output frequency range: 20 kHz to 1 MHz
•On/off (sequence control) pins provided for each channel for easy sequence control setup
•The negative supply error amplifier supports 0-volt input.
  Common-mode input voltage range: −0.1 V to VCC −1.4 V
  This allows the number of external components to be reduced by two resistors.
•Fixed duty factor: 86% However, the duty can be adjusted to anywhere from 0% to 100% with an external resistor.
•Timer latch short-circuit protection circuit (charge current: 1.1 µA typical)
•Low input voltage malfunction prevention circuit (U.V.L.O.) (operation start voltage: 1.67 V typical)
•Standby function (active-high control input, standby mode current: 1 µA maximum)
•Alternate package versions also available.
  Part No.: AN8049FHN
  Package: QFN-24
              0.5-mm lead pitch
              5.4 mm ×4.4 mm ×t0.8 mm

■Applications
•Electronic equipment that requires a power supply system