GENERAL DESCRIPTION

The LT7170/LT7170-1 are monolithic DC/DC synchronous stepdown

regulators that deliver up to 20 A of continuous output

current. The LT7170-1 option has two switching phases that are

connected to two inductors to drive a single-regulated output supply.

The quick, clean, low-overshoot switching edges deliver high

efficiency while minimizing electromagnetic interference (EMI) emissions.

The I2C-based PMBus 1.3-compliant serial interface enables

control of device functions while providing telemetry information

for system monitoring. The LT7170/LT7170-1 are supported by the

LTpowerPlay® graphical user interface (GUI) tool.

The controlled on-time valley current-mode control with 25 ns

typical minimum on-time enables a high switching frequency (fSW)

at a low output voltage (VOUT) with excellent transient response in a

small overall solution size.

VOUT, fSW, and phase are selectable using external configuration

resistors. Settings can also be set via the PMBus interface or stored

in the on-chip, three times programmable nonvolatile memory

(NVM).

To guarantee clean start-up of the powered devices, the LT7170/

LT7170-1 actively pull down the output using VSENSEP when the

output is disabled. The LT7170/LT7170-1 wait until the VOUT is less

than 0.2 V before enabling the output and beginning a soft start.

This VOUT discharge threshold is programmable from 0.2 V to 2.2 V.

The LT7170/LT7170-1 use forced-continuous switching operation.

FEATURES

► Silent Switcher® architecture: enables a compact, efficient, low

EMI solution

► PMBus/I2C serial interface

► Telemetry read back includes VOUT, IOUT, VIN, die temperature,

and faults

► Programmable voltage, current limit, sequencing, soft start

and stop, undervoltage and overvoltage, phase, frequency (up

to 4 MHz), and loop compensation

► Integrated three times programmable NVM

► Key parameters selectable by resistor

► VOUT set point range: 0.4 V to 5.5 V

► VOUT accuracy: ±0.25, 0.6 V ≤ VOUT ≤ 1.375 V

► Differential remote VOUT sense

► Fast transient response

► Wide VIN supply range: down to 2.9 V or 1.5 V with EXTVCC

► Programmable and synchronizable: 400 kHz to 4 MHz

► 24-lead (3.5 mm × 4 mm) LQFN package

APPLICATIONS

► Communications, storage, and industrial systems

► Data center and solid state drives