19-1227; Rev 1; 6/97
KIT ATION EVALU E L B A IL AVA
High-Speed Step-Down Controllers with Synchronous Rectification fo...
19-1227; Rev 1; 6/97
KIT ATION EVALU E L B A IL AVA
High-Speed Step-Down Controllers with Synchronous Rectification for CPU Power
____________________________Features
o Better than ±1% Output Accuracy Over Line and Load o 90% Efficiency o Excellent Transient Response o Resistor-Programmable Fixed Switching Frequency from 100kHz to 1MHz o Over 35A Output Current o Digitally Programmable Output from 1.1V to 3.5V in 100mV Increments (MAX1624) o Resistor-Adjustable Output down to 1.1V (MAX1625) o Remote Sensing o Adjustable AC Loop Gain (MAX1624) o GlitchCatcher™ Circuit for Fast Load-Transient Response (MAX1624) o Power-Good (PWROK) Output o Current-Mode Feedback o Digital Soft-Start o Strong 2A Gate Drivers o Current-Limited Output
_______________General Description
The MAX1624/MAX1625 are ultra-high-performance, step-down DC-DC controllers for CPU power in high-end computer systems. Designed for demanding applications in which output
voltage precision and good transient response are critical for proper operation, they deliver over 35A from 1.1V to 3.5V with ±1% total accuracy from a +5V ±10% supply. Excellent dynamic response corrects output transients caused by the latest dynamically clocked CPUs. These controllers achieve over 90% efficiency by using synchronous rectification. Flying-capacitor bootstrap circuitry drives inexpensive, external N-channel
MOSFETs. The switching frequency is resistor programmable from 100kHz to 1MHz. High switching frequencies allow the use of...