Operation
5
SNVU636 – November 2018
Copyright © 2018, Texas Instruments Incorporated
LMR36015xxxEVM User’s Guide
2
Operation
2.1
Quick Start
1. Connect the voltage supply between VIN and GND screw terminal connectors using short and thick
wires.
2. Connect the load between VOUT and GND screw terminal connectors using short and thick wires.
3. Set the supply voltage at an appropriate level between 4.2 V to 60 V. Set the current limit of the supply
to an appropriate level.
4. Turn on the power supply. With the default configuration, the EVM powers up and provides V
OUT
= 5 V.
5. Monitor the output voltage. The maximum load current must be 1.5 A with the LMR36015-Q1 device.
2.2
Efficiency Measurement
1. Connect power supply to VIN and GND screw terminal connectors and make sure the power supply
provides sufficient current.
NOTE:
There is no reverse polarity protection or fuse on the evaluation board.
2. Connect electronic load to VOUT and GND screw terminal connectors. For all power wires it is
preferable to use twisted lab wires. If the power supply wires are very long > 50 cm, solder an
additional 470-µF, 100-V bulk capacitor to posts VIN and GND. Use sufficient power wires to avoid
voltage drops, and use short sense probe connection for the measurement.
NOTE:
These sense lines are not designed to carry power.
3. To accurately sense input and output voltage use the test points VINS, VOUTS, and GNDS.
Alternatively, sense wires can be soldered directly over input capacitors C
IN1
or C
IN2
and the output
capacitors C
O1
or C
O2
.
4. Make sure the IC is enabled by having jumper J5 set to [EN-VIN] and check that test point EN is driven
high. While measuring I
Q
(unloaded input current) remove all the input and output voltage probes that
are most likely causing additional current draw.
2.3
Measure Load Transient
1. Connect power supply to VIN and GND screw terminal connectors, and make sure the power supply
can provide sufficient peak current.
NOTE:
There is no reverse polarity protection or fuse on the evaluation board.
2. Connect transient load to VOUT and GND screw terminal connectors. For all power wires use
preferable twisted lab wires. If the power supply wires are very long > 50 cm, solder an additional 470-
µF, 100-V bulk capacitor to posts VIN and GND. Use short sense probe connection for the
measurement.
3. To accurately sense the output voltage, place the scope probe directly over the output capacitors C
O1
or C
O2
. Make sure to connect scope probe GND ring directly to the output capacitor GND pad for
minimal ground loop. Ground loops can introduce ringing in observed waveforms, which is an artifact
and not present on the PCB. Alternatively, use differential probe over output capacitors C
O1
or C
O2
. Do
not use wires to differential probe and always probe directly with shortest possible pins. Make sure the
IC is enabled by having jumper J5 set to [EN-VIN] and check test point EN is driven high and not
drooping during the load transient.
