Datasheet

EVAL-ADP1715/ADP1716
Rev. 0 | Page 7 of 8
GROUND CURRENT MEASUREMENTS
06309-010
SS/ADJ/TRK
µA
GND
VIN
GND EN GND
VOUT
R1
R2
C3
J1
GND
U1
C2C1
EVAL-ADP1715/ADP1716
LOAD
VOLTAGE SOURCE
CURRENT METER
Figure 10.
Figure 10 shows how the evaluation board can be connected to
a voltage source and a current meter for ground current measure-
ments. 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 the voltage source used can supply
adequate current for the expected load levels.
Follow these steps to connect to a voltage source and current meter:
1. Connect the positive terminal (+) of the voltage source to
the VIN pad on the evaluation board.
2. Connect the positive terminal (+) of the current meter to
one of the GND pads of the evaluation board.
3. Connect the negative terminal (–) of the current meter 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.
5. The voltage source can now be turned on. If J1 is inserted
(this connects EN to VIN for automatic startup), then the
regulator powers up.
GROUND CURRENT CONSUMPTION
Ground current measurements are a way of determining how
much current the regulator internal circuits are consuming
while performing the regulation function. To be efficient, the
regulator must consume as little current as possible. Typically,
the regulator consumes maximum current when supplying its
largest load level (500 mA).
Figure 11 shows typical ground
current consumption for various load levels.
0.1 1000
06309-011
I
LOAD
(mA)
I
GND
(µA)
1 10 100
0
500
450
400
350
300
250
200
150
100
50
0
Figure 11. Ground Current vs. Load Current
When the device is disabled (EN = 0 V), ground current is
reduced to less than 1 μA.
Note that larger ground current levels are observed when using
an evaluation board with R1 and R2 present.