FEATURES
n Quad Digitally Adjustable Analog Loops with Digital
Interface for Control and Monitoring
n Wide Input Voltage Range: 4.5V to 16V
n Output Voltage Range: 0.5V to 3.3V
n ±0.5% Maximum DC Output Error Over Temperature
n ±4% Current Readback Accuracy: 0°C to 125°C
n Integrated Input Current Sense Amplifier
n 400kHz PMBus-Compliant I2C Serial Interface
n Supports Telemetry Polling Rates Up to 125Hz
n Integrated 16-Bit ∆Σ ADC
n Parallel and Current Share Multiple Modules
n 15mm × 22mm × 8.17mm BGA Package
Readable Data:
n Input and Output Voltages, Currents, and Temperatures
n Running Peak Values, Uptime, Faults and Warnings
n Onboard EEPROM Fault Log Record
Writable Data and Configurable Parameters:
n Output Voltage, Voltage Sequencing and Margining
n Digital Soft-Start/Stop Ramp, Program Analog Loop
n OV/UV/OT, UVLO, Frequency and Phasing

APPLICATIONS
n Multi-Rail Processor Power, Configurable Core Power

DESCRIPTION
The LTM®4681 is a quad 31.25A or single 125A stepdown µModule® (power module) DC/DC regulator featuring remote configurability and telemetry-monitoring
of power management parameters over PMBus. The
LTM4681 is comprised of digitally programmable analog
control loops, precision mixed-signal circuitry, EEPROM,
power MOSFETs, inductors and supporting components.
The LTM4681’s 2-wire serial interface allows outputs
to be margined, tuned and ramped up and down at programmable slew rates with sequencing delay times. True
input current sense, output currents and voltages, output
power, temperatures, uptime and peak values are readable. Custom configuration of the EEPROM contents is not
required. At start-up, output voltages, switching frequency,
and channel phase angle assignments can be set by pinstrapping resistors. The LTpowerPlay® GUI and DC1613
USB-to-PMBus converter and demo kits are available.
The LTM4681 is offered in a 15mm × 22mm × 8.17mm
BGA package available with SnPb or RoHS compliant
terminal finish.