7 Current Limit Configuration
The TPS272C45EVM has the ability to configure both the ILIM1 and ILIM2 pins of the TPS272C45 to set a wide
range of current limits that are custom tailored to the end design. Additionally the user is able to custom tailor
the duration of time taken before the output current shuts off through the resistor connected to the ILIMD pin.
The external current limits of the TPS272C45EVM are controlled by external resistors
R13
and
R14
(ILIM1),
R2
(ILIM2), and
R3
(ILIMD). Note that these resistors are populated in the 0805 package size allowing for easy
soldering and desoldering.
The ILIM1 pin is configured in such a way that multiplexed current limits can be selected from an external
microcontroller through the BoosterPack headers. This feature can seen below in
:
Figure 7-1. Multiplexed Current Limit
With this configuration, the user can choose to enable the MOSFET
Q1
if the 10.0-kΩ resistor is desired or
enable the MOSFET
Q2
if the 4.99-kΩ resistor is desired. TI does not recommend to enable both channels
simultaneously as this would parallel both of the resistors and add an undesired capacitance to the line. If
multiplexing is not needed, the user can manually populate either the
J14
or
J15
jumpers. Please refer to the
TPS272C45 data sheet for information on how to calculate delays from relevant resistor values.
Current Limit Configuration
10
TPS272C45 Evaluation Module
SLVUBV4A – DECEMBER 2020 – REVISED DECEMBER 2021
Copyright © 2021 Texas Instruments Incorporated
