Table of Contents
Advertisement
www.ti.com
3 Detailed Descriptions
3.1 Connectors
This section describes the connectors on the EVM and how to properly connect, set up, and use the EVM. See
Figure 2-1
for a top view of the EVM.
VOUT
Output voltage of the converter
The VOUT connector connects to the power inductor and output capacitors. Connect the load
between VOUT connector and the GND connector right next to it to provide load current. Connect
the loading device to the board with short and thick wires to handle the large DC output current.
GND1-
Ground of the converter
GND5
The GND is connected to the PGND and AGND pins of the device, as well as the ground of the
input and output capacitors. The GND connections next to VIN, VIN_EMI, and VOUT connectors
are meant for current return path for the supply voltage and load, respectively. Connectors are
provided in pairs to allow easy and accurate sensing of voltages. Connect to supply and load
grounds with short and thick wires. Other GND connectors are for signal measurement and
probing.
VIN
Input voltage to the converter
The VIN connector connects to the input capacitors and the VIN pins of the LMR51450. Connect
the supply voltage from a power supply or a battery between VIN and GND connectors as power
input to the device. The voltage range must be higher than 3.9 V for the device to start up. VIN
higher than 6 V provides regulated 5-V output voltage. VIN must be no higher than 36 V to avoid
damaging the device. After start-up, the device stays active until VIN drops below 3.4 V. The
current limit on the supply must be high enough to provide the needed supply current. Otherwise,
the supply voltage does not maintain the desired voltage. The supply voltage must be connected
to the board with short and thick wires to handle the pulsing input current.
VIN_EMI
Input voltage to input filter of the converter
LMR51450 EVM provides the option for the use of input filter. C1, C2 and L4 are placeholders
for input filter networks to be populated. If the input filter is desired between the supply and the
LMR51450, put C1, C2, and L4 on the board and connect the supply voltage between VIN_EMI
and GND_EMI connectors. The supply voltage must be connected to the board with short and
thick wires to handle pulsing input current. The output of the filter is connected to VIN, which is
connected to the VIN pins of the LMR51450 and the input capacitors.
GND_EMI
Ground return for the input filter
This connector is the current return path for the supply connected to VIN_EMI. This connector
provides a short-loop connection to the input filter capacitors to best filter the conducted noise
generated from the PCB. Use VIN_EMI and GND_EMI connection if input filter is used and
conducted EMI test is desired.
EN
To monitor the EN pin or input EN control signal
This test point is used to monitor the voltage on the device EN pin. By default, the EN pin is
connected to Vin.
PG
To monitor the PGOOD pin
The PGOOD flag indicates whether the output voltage is within the regulation band. The PGOOD
pin of the device is an open-drain output and it is pulled up to V
resistor. This flag is high impedance when the output voltage is in regulation.
VO
This connector is provided to allow V
VI
This connector is provided to allow V
SNVU838A – OCTOBER 2022 – REVISED NOVEMBER 2022
Submit Document Feedback
to be measured more accurately.
OUT
to be measured more accurately.
IN
Copyright © 2022 Texas Instruments Incorporated
Detailed Descriptions
on this board through a pullup
OUT
LMR51450 EVM
5
Advertisement
Table of Contents
