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