IRU3038

w D w a t S ( : w h D e .e a tS h e e 4 t U c o . ) m Data Sheet No. PD94250 IRU3038 SYNCHRONOUS PWM CONTROLLER FOR TERMINATION POWER SUPPLY APPLICATIONS PRELIMINARY DATA SHEET FEATURES Synchronous Controller in 14-Pin Package Operating with single 5V or 12V supply voltage 200KHz to 400KHz operation set by an external resistor Soft-Start Function Fixed Frequency Voltage Mode 500mA Peak Output Drive Capability Uncommitted Error Amplifier available for DDR voltage tracking application 1.25V Reference Voltage Protects the output when control FET is shorted DESCRIPTION The IRU3038 controller IC is designed to provide a low cost synchronous Buck regulator for voltage tracking applications such DDR memory and general purpose on-board DC to DC converter. Modern micro processors combined with DDR memory, need high-speed bandwidth data bus which requires a particular bus termination voltage. This voltage will be tightly regulated to track the half of chipset voltage for best performance. The IRU3038 together with dual N-channel MOSFETs such as IRF7313, provide a low cost solution for such applications. This device features a programmable frequency set from 200KHz to 400KHz, under-voltage lockout for both Vcc and Vc supplies, an external programmable soft-start function as well as output under-voltage detection that latches off the device when an output short is detected. APPLICATIONS DDR memory source sink Vtt application Low cost on-board DC to DC such as 5V to 3.3V, 2.5V or 1.8...