General Description
The MIC2141 is a micropower boost switching regulator that can operate from 3- or 4-cell nickel-metal-hydride batteries or a single Li-ion cell. This regulator employs a constant 330kHz, fixed 18% duty-cycle, gated-oscillator architecture.
The MIC2141 can be used in applications where the output voltage must be dynamically adjusted. The device features a control signal input which is used to proportionally adjust the output voltage. The control signal input has a gain of 6, allowing a 0.8V to 3.6V control signal to vary a 4.8V to 22V output.
The MIC2141 requires only three external components to operate and is available in a tiny 5-lead SOT-23 package for space and power-sensitive portable applications. The MIC2141 draws only 70µA of quiescent current and can operate with an efficiency exceeding 85%.
FEATUREs
• Implements low-power boost, SEPIC, or flyback
• 2.5V to 14V input voltage
• 330kHz switching frequency
• <2µA shutdown current
• 70µA quiescent current
• 1.24V bandgap reference
• typical output current 1mA to 10mA
• SOT-23-5 Package
APPLICATIONs
• LCD bias supply
• CCD digital camera supply