LM2720

OBSOLETE LM2720 www.ti.com SNVS081B – MAY 2004 – REVISED MARCH 2009 LM2720 5-Bit Programmable, High Frequency Multi-phase PWM Controller Check for Samples: LM2720 FEATURES 1 2 Ultra Fast Load Transient Response Enables All Surface-Mount-Design Selectable 2, 3, 4 Phase Operation Clock Frequency from 40 kHz to 10 MHz Precision Load Current Sharing 5-bit Programmable from 3.5V to 1.3V VID Code Compatible to VRM 8.X Specification Output Voltage is 2.0V for VID Code 11111 Selectable Internal or External Clock Digital 16-Step Soft Start Input Under-Voltage Lock-Out, Over-Current Protection Open-Drain Power Good Signal Output APPLICATIONS Servers and Workstations High Current, Ultra-Fast Transient Microprocessors DESCRIPTION The LM2720 provides an attractive solution for power supplies of high power microprocessors exhibiting ultra fast load transients. Compared to a conventional single-phase supply, an LM2720 based multi-phase supply distributes the thermal and electrical loading among components in multiple phases and greatly reduces the corresponding stress in each component. The LM2720 can be programmed to control either a 3-phase converter or a 4-phase converter. Phase shift among the phases is 120° in the case of three phase and 90° with four-phase. Because the power channels are out of phase, there can be significant ripple cancellation for both the input and output current, resulting in reduced input and output capacitor size. Due to the nomi...