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1 Background
The TPS65400 is an integrated power management unit (PMU) optimized for applications that require small form
factor and high-power conversion efficiency, enabling small space-constrained equipment with high-ambient
operating temperature without cooling. The TPS65400 provides high-power efficiency at a system level by
enabling a single-stage conversion from an intermediate distribution bus with an optimized combination of
regulators.
The TPS65400 consists of four high-current buck-switching regulators (SW1, SW2, SW3, and SW4) with
integrated FETs. The switching power supplies are intended for powering high-current digital circuits such as
the processor, FPGA, ASIC, memory, and digital I/Os. SW1 and SW2 support 4 A each, and SW3 and SW4
support 2 A each. Each regulator’s switching frequency is independently adjustable up to 2.2 MHz.
Current limit programmability on each switcher enables optimization of inductor ratings for a particular
application configuration not requiring the maximum current capability. The TPS65400 can be powered from
a single-input voltage rail between 4.5 and 18 V, making it suitable for applications running off a 5- or 12-V
intermediate power distribution bus. Sequencing requirements can be met using the individual enable pins or by
programming the sequence through the I
2
C bus into the onboard EEPROM. Output voltages can be set through
external resistor networks and VREF can be programmed from 0.6 to 1.87 V in 10-mV steps. All control and
status info can be accessed through a PMBus-compatible I
2
C bus.
The TPS65400 provides a high level of flexibility for monitoring and control through the I
2
C bus while providing
the option of programmability through the use of external components and voltage levels for systems not using
I
2
C. As there are many possible options to set the converters,
presents the performance specification
summary for the EVM.
The evaluation module is designed to provide access to the features of the TPS65400. Some modifications can
be made to this module to test performance at different input and output voltages for bucks. Please contact the
TI Field Applications group for advice on these matters.
As there are many possible options to set the converters,
presents the performance specification
summary for the EVM.
Table 1-1. Summary of Performance
Test Conditions
Performance
VIN = 4.5 to 18 V
fsw = 500 kHz (25°C ambient)
Buck1, 1.8 V, up to 4 A
Buck2, 3.3 V, up to 4 A
Buck3, 1.2 V, up to 2 A
Buck4, 2.5 V, up to 2A
Background
2
TPS65400 Buck Converter Evaluation Module User's Guide
SLVUAC4A – OCTOBER 2014 – REVISED MAY 2021
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