LTC3711 - 5-Bit Adjustable, Wide Operating Range, No RSENSE™ Step-Down Controller

The LTC®3711 is a synchronous step-down switching regulator controller for CPU power. An output voltage between 0.925V and 2.000V is selected by a 5-bit code (Intel mobile VID specification). The controller uses a valley current control architecture to deliver very low duty cycles without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in VIN and VOUT.

Discontinuous mode operation provides high efficiency operation at light loads. A forced continuous control pin reduces noise and RF interference and can assist secondary winding regulation by disabling discontinuous mode operation when the main output is lightly loaded.

Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and optional short-circuit shutdown timer. Soft-start capability for supply sequencing is accomplished using an external timing capacitor. The regulator current limit level is user programmable. Wide supply range allows operation from 4V to 36V at the input.

特点
  • 5-Bit Programmable Output Voltage: 0.925V to 2V
  • No Sense Resistor Required
  • True Current Mode Control
  • 2% to 90% Duty Cycle at 200kHz
  • tON(MIN) < 100ns
  • Supports Active Voltage Positioning
  • Extremely Fast Transient Response
  • Stable with Ceramic COUT
  • Dual N-Channel MOSFET Synchronous Drive
  • Power Good Output Voltage Monitor
  • Wide VIN Range: 4V to 36V
  • ±1% 0.8V Reference
  • Adjustable Current Limit
  • Adjustable Switching Frequency
  • Programmable Soft-Start
  • Output Overvoltage Protection
  • Optional Short-Circuit Shutdown Timer
  • Micropower Shutdown: IQ < 30µA
  • Available in 24-Lead Narrow SSOP Package
典型应用
LTC3711 Typical Application
LTC3711 Typical Application
应用
  • Power Supplies for Mobile Pentium® Processors
  • Notebook and Palmtop Computers, PDAs
封装信息
LTC3711 Package Drawing
Order Information 订购型号
器件型号封装温度价格 (以 1 ~ 99 片为批量)价格 (以 1000 片为批量) *
LTC3711EGN#PBFSSOP-24E$4.14$3.50
LTC3711EGN#TRPBFSSOP-24E$3.60
数据表
设计要点
可靠性数据
LT Journal
CAD 符号
相关产品
LTC3711 - 5-Bit Adjustable, Wide Operating Range, No Rsense Step-Down Controller
Design Solutions 10 - Active Voltage Positioning Reduces Output Capacitors
R384 Reliability Data
Feb 2001 New No Rsense Controllers Deliver Very Low Output Voltages
LTC3711 Footprints and Symbols