General Description

Micrel’s MIC2184 is a high efficiency PWM buck control IC. With its wide input voltage range of 2.9V to 14V, the MIC2184 can be used to efficiently step voltages down in 1- or 2-cell LiIon battery powered applications, as well as in fixed 3.3V, 5V, or 12V systems.

Efficiencies over 90% are achievable over a wide range of load conditions with the MIC2184’s PWM control scheme. The operating frequency can be divided by two by raising the FREQ/2 pin to VDD. This allows the user to optimize efficiency versus board space. It also allows the MIC2184 to be externally synchronized to frequencies below its nominal 400KHz.

Features

• Input voltage range: 2.9V to 14V

• >90% efficiency

• Oscillator frequency of 400kHz

• Frequency divide-by-two pin

• Frequency sync to 600kHz

• FrequOut oscillator output allows simple charge pump implementation in low voltage systems

• 1.245V reference output

• Front edge blanking

• 5Ω output driver

• Soft start

• PWM current mode control

• 1µA shutdown current

• Cycle-by-cycle current limiting

• Frequency foldback short circuit protection

• Adjustable under-voltage lockout

• 16 pin narrow-body SOIC and QSOP package options

Applications

• 3.3V to 2.5V/1.8V/1.5V conversion

• DC power distribution systems

• Wireless Modems

• ADSL line cards

• 1-and 2-cell Li Ion battery operated equipment

• Satellite Phones