AIC1577

Features:

N-Channel MOSFET Drive
Operating Input Voltage from 4.5V to 24V
Wide Ouput Range : 0.8V to 20V
1.5% 0.8V Reference
Low Dropout Operation : 95% Duty Cycle
500KHz Fixed Constant Frequency
Low Standby Current, IQ Typically 720mA
Logic-Control Micropower Shutdown
Output Overvoltage Protection
Internal Diode for Bootstrapped Gate Drive
Current Mode Operation for Excellent Line and Load Transient Response
Available in an 8-Lead SO and MSOP Package

Application

LCD Monitor
Palmtop Computers, PDAs
Wireless Modems
On-Card Switching Regulators
DC Power Distribution Systems

Pinout

TYPICAL APPLICATION

Description

The AIC1577 is a current mode switching regulator controller that drives external N-channel power MOSFET using a fixed fre-quency architecure. It uses external divider to adjust output voltage from 0.8V to 20V with excellent line and load regulation. A maximum high duty cycle limit of 95% provides low dropout operation which extends operating time in battery-operated systems.
Switching frequency up to 500KHz are achievable thus allowing smaller sized filter components. The operating current level is user-programmable via an external current sense resistor. AIC1577 also provide output over-voltage protection under fault conditions.
A multifunction pin (ITH/RUN) allows external compensation for optimum load step re-sponse plus shutdown. Soft start can also be implemented with this pin to properly se-quence supplies. Package of AIC1577 available are in SOP8 and MSOP8 for SMD.