Datasheet

UG-136 Evaluation Board User Guide
Rev. A | Page 6 of 12
GROUND CURRENT MEASUREMENT
Follow these steps to connect to a voltage source and ammeter:
Figure 9 and Fi
gure 10 show how the evaluation boards can be
co
nnected to a voltage source and an ammeter for ground current
measurements. A resistor can be used as the load for the regulator.
Ensure that the resistor has a power rating adequate to handle
the power expected to be dissipated across it. An electronic load
can be used as an alternative. Ensure that the voltage source used
can supply enough current for the expected load levels. If
voltmeters are connected at the input or output terminals,
subtract the current resulting from the shunt resistance of
the voltmeter for accurate ground current measurement.
1. Connect the positive terminal (+) of the voltage source to
the VIN pad on the evaluation board.
2. Connect the positive terminal (+) of the ammeter to the
GND pad of the evaluation board.
3. Connect the negative terminal (−) of the ammeter to the
negative (−) terminal of the voltage source.
4. Connect a load between the VOUT pad of the evaluation
board and the negative (−) terminal of the voltage source.
The voltage source can now be turned on. If J2 is inserted
(connecting EN to VIN for automatic startup), the switch
powers up.
VOLTAGE SOURCE
VIN
AMMETER
GND CURRENT
0.035
08996-006
LOAD
Figure 9. 4-Ball WLCSP Ground Current Measurement
+
-
AMMETER
+-
VOLTAGE SOURCE
LOAD
0.00112
08996-010
Figure 10. 6-Lead LFCSP Ground Current Measurement