Features

• 2.25V to 5.5V Input Voltage Range
• ±1% Total Output Voltage Accuracy Over Temperature at V_IN = 3.3V or 5V
• Single Resistor-Programmable Output Voltage
• PMBus Compliant Serial Interface:
  Programmable Output Voltage Margining: Up to ±25% V_OUT Range with 0.1% Resolution
  Read back of Average and Peak Temperature, Current, and Voltage (25Hz Refresh Rate)
  Fault Status
• Phase-Lockable Fixed Frequency Up to 3MHz
• Less Than 1ms Power-Up Time
• Integrated 13-Bit ADC
• Optional External Reference Input
• Pin Selectable Fast-Margining of the Output Voltage
• Power Good Flag with Pin Programmable Thresholds and Filter Delay
• Differential Remote Output Voltage Sensing
• Master Shutdown Mode: <1μA Supply Current
• Clock Out for 2-Phase Operation (12A Output Current)
• Available in a Thermally-Enhanced 38-Lead 4mm × 6mm QFN Package
• Download LTpowerPlay Software

Typical Application

Description

The LTC®3815 is a high efficiency, 6A monolithic synchronous buck regulator using a phase lockable controlled on-time, current mode architecture. The output voltage is programmable from 0.4V to 72% of V_IN with a single external resistor or an external voltage reference through the reference input (REF) pin. The output voltage can be margined up or down up to ±25% with 0.1% resolution via a PMBus-compliant serial interface. The serial interface can also be used to read back fault status and both timeaveraged (~4ms) and peak input/output current, input/ output voltage and temperature. System configuration and monitoring is supported by the LTpowerPlay^® development system.

The architecture provides extremely fast transient response and allows operation at the very low on-times required to regulate low output voltages at high switching frequencies. The operating frequency is programmable from 400kHz to 3MHz with an external resistor or for noise sensitive applications, it can be synchronized to an external clock over the same range. The operating supply voltage range is from 2.25V to 5.5V making it suitable for operation from 2.5V, 3.3V or 5V rails or Lithium-Ion batteries.