Test Setup
4
Test Setup
4.1
Test Equipment
Voltage source VIN:
The input voltage source VIN must be a 0-V to 20-V variable DC source capable of
supplying 10 ADC. Connect VIN to J102 (as shown in
Voltage source V5VIN:
The input voltage source V5VIN must be a 0-V to 5-V variable DC source
capable of supplying 1 ADC. Connect V5VIN to J100 (as shown in
Multimeters:
•
V1: VIN at TP103 (Vins) and TP104 (GNDS)
•
V2: 5V at TP100 (5V) and TP101 (GND)
•
V3: Vouts at TP107 (Vouts) and TP108 (GNDS)
•
A1: VIN input current
•
A2: 5V input current
Output load:
The output load must be an electronic constant-resistance mode load capable of 0-ADC to
20-ADC at 1.35 V.
Oscilloscope:
A digital or analog oscilloscope can be used to measure the switch node waveform.
Differential probe must be used for the switch node waveform measurements. The oscilloscope should be
set for 50-
Ω
impedance, 1-GHz bandwidth, DC coupling, 50-ns/division horizontal resolution, 5-V/division
vertical resolution. When measuring the switch node waveform, place the negative probe tip on the GND
pad of the input cap and positive tip on the CSD87381P Vsw top metal (as shown in
).
Figure 2. Tip and Barrel Measurement for Vsw Waveform
Fan:
Some of the components in this EVM may approach temperatures of 60°C during operation. TI
recommends a small fan capable of 200 to 400 LFM to reduce component temperatures while the EVM is
operating. The fan needs to run when the load current is higher than 10 A.
Recommended Wire Gauge:
1. VIN to J102 (8-V to 20-V input):
The recommended wire size is 1x AWG number 14 per input connection, with the total length of wire
less than 4 ft (2 ft input, 2 ft return).
2. V5VIN to J100 (5-V input):
The recommended wire size is 1x AWG number 18 per input connection, with the total length of wire
less than 4 ft (2 ft input, 2 ft return).
3. J103 to LOAD:
The minimum recommended wire size is 2x AWG number 14, with the total length of wire less than 4 ft
(2 ft output, 2 ft return).
4
High Power Density, Low Profile NexFET™ Power Block II for Notebook
SLPU003A – February 2014 – Revised February 2014
Power Supply
Copyright © 2014, Texas Instruments Incorporated