描述 Description

The LM25117 is a synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.

特性 Features

? Emulated peak current mode control
? Wide operating range from 4.5V to 42V
? Robust 3.3A peak gate drives
? Adaptive dead-time output driver control
? Free-run or synchronizable clock up to 750kHz
? Optional diode emulation mode
? Programmable output from 0.8V
? Precision 1.5% voltage reference
? Analog current monitor
? Programmable current limit
? Hiccup mode over current protection
? Programmable soft-start and tracking
? Programmable line under-voltage lockout
? Programmable switch-over to external bias supply
? Thermal shutdown
Packages
? TSSOP-20EP (Thermally enhanced)
? LLP-24 (4mmx4mm)