描述 Description

The LM2676 series of regulators are monolithic integrated circuits which provide all of the active functions for a step-down (buck) switching regulator capable of driving up to 3-A loads with excellent line and load regulation characteristics. High efficiency (>90%) is obtained through the use of a low ON-resistance DMOS power switch. The series consists of fixed output voltages of 3.3-V, 5-V, and 12-V and an adjustable output version.

The SIMPLE SWITCHER? concept provides for a complete design using a minimum number of external components. A high fixed frequency oscillator (260?kHz) allows the use of physically smaller sized components. A family of standard inductors for use with the LM2676 are available from several manufacturers to greatly simplify the design process.

The LM2676 series also has built-in thermal shutdown, current limiting and an ON/OFF control input that can power down the regulator to a low 50?μA quiescent current standby condition. The output voltage is ensured to a ±2% tolerance. The clock frequency is controlled to within a ±11% tolerance.

The new product, LMR33630, offers reduced BOM cost, higher efficiency, and an 85% reduction in solution size among many other features. See the Device Comparison Table to compare specs. Start a WEBENCH Design with LMR33630.

特性 Features

? New product available: LMR33630 36-V, 3-A, 400-kHz synchronous converter
? Efficiency up to 94%
? Simple and easy to design with (using off-the-shelf external components)
? 150-mΩ DMOS output switch
? 3.3-V, 5-V, 12-V Fixed output and adjustable (1.2 V to 37 V) versions
? 50-μA Standby current when switched OFF
? ±2% Maximum output tolerance over full line and load conditions
? Wide input voltage range: 8 V to 40 V
? 260-KHz Fixed frequency internal oscillator
? –40 to 125°C Operating junction temperature range