The UCC33420EVM-080 EVM utilizes screw terminals for easily connecting to VINP and
VCC. EN connections are made through pin connectors. Connecting the appropriate
ammeters and voltmeters, as shown in Figure 4‑1, allows accurate EVM efficiency
measurements.
Connecting Test Equipment:
- Connect the VINP DC power supply
capable of 4.5V<VINP<5.5V, 1A at J1:1-2 (VINP-GNDP). With the power supply
disable, adjust the power supply to 5.0V, and set the current limit to 4A.
- Connect a power supply capable of
5V, 100mA at J2:2-1 to serve as the pull up bias for EN/FLT. With the supply
disabled, set to 3.3V/5.0V. As an option, the user can use the input power
supply as a bias supply connecting a jumper to short +VINP and EN pins at J2:1-2
(top left corner).
- Connect a variable load between
J3:1 (VCC) and J3:2 (GNDS). If using an electronic load, then set to constant
current (CC), 300mA. Leave the load disabled until the EVM is powered.
- Some electronic loads are not
able to regulate or stabilize CC when setting in the low mA range. Monitor the
input current and load currents by inserting ammeters as shown in Figure 2-1. A
current probe can be used with the oscilloscope to verify the stability of the
DC current being regulated by an electronic load.