LM2637MX

Product Summary

The LM2637MX is a motherboard power supply solution with a 5-bit programmable switching controller and two linear regulator controllers. The LM2637MX provides a comprehensive embedded power supply solution for motherboards hosting high performance MPUs such as M II., Pentium. II, K6-2 and other similar high performance MPUs. The LM2637MX incorporates a 5-bit programmable, synchronous buck switching controller and two high-speed linear regulator controllers in a 24-pin SO package. Switching Section — The switching regulator controller features a 5-bit programmable DAC, over-current and overvoltage protection, under-voltage latch-off, a power good signal, and output enable. The 5-bit DAC has a typical tolerance of 1%. There are two user-selectable over-current protection methods. One provides accurate over-current protection with the use of an external sense resistor. The other saves cost by taking advantage of the LM2637MX highside FET. The over voltage protection provides two levels of protection. The first level keeps the high-side FET off and the low-side FET on. The second provides a gate signal that can be used to fire an external SCR.

Parametrics

LM2637MX absolute maximum ratings: (1)VCC: 7V; (2)VDD: 17V; (3)Junction Temperature: 150℃; (4)Power Dissipation: 1.6W; (5)Storage Temperature: -65℃ to +150℃; (6)ESD Susceptibility: 2.5 kV; (7)Soldering Time, Temperature (10 sec.): 300℃.

Features

LM2637MX features: (1)Provides 3 regulated voltages; (2)Power Good flag and output enable; (3)Under-voltage latch-off. Switching Section; (4)Synchronous rectification; (5)5-bit DAC programmable from 3.5V to 1.3V; (6)Typical 1% DAC tolerance; (7)Switching frequency: 50 kHz to 1 MHz; (8)Two levels of over-voltage protection; (9)Two methods of over-current protection; (10)Adaptive non-overlapping FET gate drives; (11)Soft start without external capacitor Linear Section; (12)N-FET and NPN driving capability; (13)Ultra fast response speed; (14)Output voltages default to 1.5V and 2.5V yet adjustable.

Diagrams