LTC1876 High Efficiency, 2-Phase, Dual Synchronous Step-Down Switching Controller and Step-Up Regulator

The LTC®1876 is a high performance triple output switching regulator. It incorporates a dual step-down switching controller that drives all N-channel synchronous power MOSFET stages. A step-up regulator with an internal 1A, 36V switch provides the third output.

The step-down controllers minimize power loss and noise by operating the output stage of each controller out of phase. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. A RUN/SS pin for each controller provides both soft-start and an optional timed, short-circuit shutdown that can be configured to latch offone or both controllers. Current foldback provides additional short-circuit protection. In an overvoltage condition, the bottom MOSFET is latched on until VOUT returns to normal. The FCB pin can be used to inhibit Burst Mode operation or to enable regulation of a secondary output voltage.

The step-up regulator operates at 1.2MHz, allowing the use of tiny low cost capacitors and inductors. In addition,its internal 1A switch allows high current outputs to be generated. Its current mode control scheme provides excellent line and load regulation

产品特点 Features
  • Step-Down Controller
  • Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
  • Power Good Output Voltage Indicator
  • OPTI-LOOP™ Compensation Minimizes COUT
  • DC Programmed Fixed Frequency 150kHz to 300kHz
  • Wide VIN Range: 3.5V to 36V Operation
  • Very Low Dropout Operation: 99% Duty Cycle
  • Adjustable Soft-Start Current Ramping
  • Latched Short-Circuit Shutdown with Defeat Option
  • Remote Output Voltage Sense and OV Protection
  • 5V and 3.3V Standby Regulators
  • Selectable Const. Freq. or Burst Mode™ Operation
  • Step-Up Regulator
  • High Operating Switching Frequency of 1.2MHz
  • Low Internal VCESAT Switch: 400mV @ 1A, VIN = 3V
  • Wide VIN Range: 2.6V to 16V Operation
  • High Output Voltage: Up to 34V
应用
  • 3.3V Input Step-Down Converter
  • Notebook and Palmtop Computers, PDAs
  • Battery-Operated Digital Devices
典型应用图
LTC1876 典型应用
参数
LTC1876 参数
LTC1876 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) *
LTC1876EG SSOP 36 E $7.04  $5.95 
LTC1876EG#PBF SSOP 36 E $7.04  $5.95 
LTC1876EG#TR SSOP 36 E $6.05 
LTC1876EG#TRPBF SSOP 36 E $6.05 
LTC1876 数据手册及相关资料下载
  1. 数据手册(英文) : LTC1876 - High Efficiency, 2-Phase, Dual Synchronous Step-Down Switching Controller and Step-Up Regulator.PDF
  2. 设计要点 (英文) : Design Solutions 10 - Active Voltage Positioning Reduces Output Capacitors.PDF
  3. 可靠性数据 : R384 Reliability Data .PDF