LTC1775 High Power No RSENSE™ Current Mode Synchronous Step-Down Switching Regulator

The LTC®1775 is a synchronous step-down switching regulator controller that drives external N-channel power MOSFETs using few external components. Current mode control with MOSFET VDS sensing eliminates the need for a sense resistor and improves efficiency. Largely similar to the LTC1625, the LTC1775 has twice the maximum sense voltage for high current applications. The frequency of a nominal 150kHz internal oscillator can be synchronized to an external clock over a 1.5:1 frequency range. Burst Mode™ operation at low load currents reduces switching losses and low dropout operation extends operating time in battery-powered systems. A forced continuous mode control pin can assist secondary winding regulation by disabling Burst Mode operation when the main output is lightly loaded. Fault protection is provided by foldback current limiting and an output overvoltage comparator. An external capacitor attached to the RUN/SS pin provides soft start capability for supply sequencing. A wide supply range allows operation from 4V (4.3V for LTC1775I) to 36V at the input and 1.19V to VIN at the output

产品特点 Features
  • Highest Efficiency Current Mode Controller
  • No Sense Resistor Required
  • 300mV Maximum Current Sense Voltage
  • Stable High Current Operation
  • Dual N-Channel MOSFET Synchronous Drive
  • Wide VIN Range: 4V to 36V
  • Wide VOUT Range: 1.19V to VIN
  • ±1% 1.19V Reference
  • Programmable Fixed Frequency with Injection Lock
  • Very Low Drop Out Operation: 99% Duty Cycle
  • Forced Continuous Mode Control Pin
  • Optional Programmable Soft Start
  • Pin Selectable Output Voltage
  • Foldback Current Limit
  • Output Overvoltage Protection
  • Logic Controlled Micropower Shutdown: IQ< 30µA
  • Available in 16-Lead Narrow SSOP and SO Packages
应用
  • Notebook Computers
  • Automotive Electronics
  • Battery Chargers
  • Distributed Power Systems
典型应用图
LTC1775 典型应用
参数
LTC1775 参数
LTC1775 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) *
LTC1775CGN SSOP 16 C $5.90  $5.00 
LTC1775CGN#PBF SSOP 16 C $5.90  $5.00 
LTC1775CGN#TR SSOP 16 C $5.06 
LTC1775CGN#TRPBF SSOP 16 C $5.06 
LTC1775CS SO 16 C $5.55  $4.65 
LTC1775CS#PBF SO 16 C $5.55  $4.65 
LTC1775CS#TR SO 16 C $4.71 
LTC1775CS#TRPBF SO 16 C $4.71 
LTC1775IGN SSOP 16 I $7.35  $6.00 
LTC1775IGN#PBF SSOP 16 I $7.35  $6.00 
LTC1775IGN#TR SSOP 16 I $6.06 
LTC1775IGN#TRPBF SSOP 16 I $6.06 
LTC1775IS SO 16 I $6.85  $5.60 
LTC1775IS#PBF SO 16 I $6.85  $5.60 
LTC1775IS#TR SO 16 I $5.66 
LTC1775IS#TRPBF SO 16 I $5.66 
LTC1775 数据手册及相关资料下载
  1. 数据手册(英文) : LTC1775 - High Power No Rsense Current Mode Synchronous Step-Down Switching Regulator.PDF
  2. 可靠性数据 : R302 Reliability Data .PDF