LT1738 Slew Rate Controlled Ultralow Noise DC/DC Controller

The LT™1738 is a switching regulator controller designed to lower conducted and radiated electromagnetic interference (EMI). Ultralow noise and EMI are achieved by controlling the voltage and current slew rates of an exter-nal N-channel MOSFET switch. Current and voltage slew rates can be independently set to optimize harmonic content of the switching waveforms vs efficiency. The LT1738 can reduce high frequency harmonic power by as much as 40dB with only minor losses in efficiency.

The LT1738 utilizes a current mode architecture optimized for single switch topologies such as boost, flyback and Cuk. The IC includes gate drive and all necessary oscillator, control and protection circuitry. Unique error amp circuitry can regulate both positive and negative voltages. The internal oscillator may be synchronized to an external clock for more accurate placement of switching harmonics.

Protection features include gate drive lockout for low VIN, soft-start, output current limit, short-circuit current limit-ing, gate drive overvoltage clamp and input supply undervoltage lockout

产品特点 Features

Greatly Reduced Conducted and Radiated EMI
Low Switching Harmonic Content
Independent Control of Output Switch Voltage and Current Slew Rates
Greatly Reduced Need for External Filters
Single N-Channel MOSFET Driver
20kHz to 250kHz Oscillator Frequency
Easily Synchronized to External Clock
Regulates Positive and Negative Voltages
Easier Layout Than with Conventional Switchers

参数

应用

Power Supplies for Noise Sensitive Communication Equipment
EMI Compliant Offline Power Supplies
Precision Instrumentation Systems
Isolated Supplies for Industrial Automation
Medical Instruments
Data Acquisition Systems

典型应用图

LT1738 订购信息和价格参考Package Variations and Pricing

器件型号	封装	引脚	温度	价格 (以 1 ~ 99 片为批量)	价格 (以 1000 片为批量) *
LT1738EG	SSOP	20	E	$4.85	$4.10
LT1738EG#PBF	SSOP	20	E	$4.85	$4.10
LT1738EG#TR	SSOP	20	E		$4.20
LT1738EG#TRPBF	SSOP	20	E		$4.20
LT1738IG	SSOP	20	I	$5.50	$4.65
LT1738IG#PBF	SSOP	20	I	$5.50	$4.65
LT1738IG#TR	SSOP	20	I		$4.75
LT1738IG#TRPBF	SSOP	20	I		$4.75

LT1738 数据手册及相关资料下载

数据手册(英文) : LT1738 - Slew Rate Controlled Ultralow Noise DC/DC Controller.PDF
设计要点 (英文) : DN260 - Isolated Flyback Converter Regulates Without an Optocoupler.PDF
设计要点 (英文) : DN338 - Power over Ethernet Isolated Power Supply Delivers 11.5W at 90% Efficiency.PDF
可靠性数据 : R303 Reliability Data .PDF