LTC3720 Datasheet PDF - Linear Technology

DESCRIPTION
The LTC®3720 is a synchronous step-down switching regulator controller for CPU power. An output voltage between 1.05V and 1.825V is selected by a 5-bit code (Intel VRM8.5 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.

FEATURES
■ 5-Bit Programmable Output Voltage: 1.05V to 1.825V (VRM8.5)
■ No Sense Resistor Required
■ 2% to 87% Duty Cycle at 200kHz
■ tON(MIN) ≤ 100ns
■ Supports Active Voltage Positioning
■ True Current Mode Control
■ 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
■ Forced Continuous Control Pin
■ Programmable Soft-Start
■ Output Overvoltage Protection
■ Optional Short-Circuit Shutdown Timer
■ Micropower Shutdown: IQ < 30µA
■ Available in 28-Lead Narrow SSOP Package

APPLICATIONS
■ Power Supplies for Pentium® Processors
■ Notebook Computers and Servers