Evaluation Board User Guide UG-179
Rev. 0 | Page 3 of 12
USING THE EVALUATION BOARD
The ADP2300/ADP2301 evaluation boards are fully assembled
and tested. Before applying power to the evaluation boards, follow
the procedures in this section.
JUMPER SETTING
Jumper J5 enables the part. Connect a jumper between Position 1
and Position 2 to enable the part. Connect a jumper between
Position 2 and Position 3 to disable the part. Leave Jumper J5
open to obtain an approximately 7.8 V V
IN
start-up voltage.
Table 1. Jumper J5 (EN) Setting
State Function
High Enable the part
Low Disable the part
Open Program the V
IN
start-up voltage to be about 7.8 V
INPUT POWER SOURCE CONNECTION
Before connecting the power source to the ADP2300/ADP2301
evaluation board, make sure that the evaluation board is turned off.
If the input power source includes a current meter, use that
meter to monitor the input current. Connect the positive terminal
of the power source to the VIN terminal (J1) on the evaluation
board, and the negative terminal of the power source to the
GND terminal (J3) of the board. If the power source does not
include a current meter, connect a current meter in series with
the input source voltage. Connect the positive terminal of the
power source to the current meter’s positive lead (+), the negative
terminal of the power source to the GND terminal (J3) on the
evaluation board, and the negative lead (−) of the current meter
to the VIN terminal (J1) on the board.
OUTPUT LOAD CONNECTION
Make sure that the board is turned off before connecting the load.
If the load includes a current meter, or if the current is not
measured, connect the load directly to the demonstration board
with the positive (+) load connection to the VOUT terminal (J2)
and negative (−) load connection to the GND terminal (J4). If a
current meter is used, connect it in series with the load; connect
the positive (+) current meter terminal to the evaluation board
VOUT terminal (J2), the negative (−) current meter terminal to
the positive (+) load terminal, and the negative (−) load terminal to
the evaluation board GND terminal (J4).
INPUT AND OUTPUT VOLTMETER CONNECTIONS
Measure the input and output voltages with voltmeters. Make
sure that the voltmeters are connected to the appropriate test
point on the board. If the voltmeters are not connected to the
right test point, the measured voltages will be incorrect due to
the voltage drop across the leads and/or connections between
the board, the power source, and/or the load.
Connect the input voltage measuring the voltmeter’s positive
terminal (+) to the input capacitor (C2) positive terminal and the
negative (−) terminal to the input capacitor (C2) negative
terminal.
Connect the output voltage measuring the voltmeter’s positive (+)
terminal to the output capacitor (C3 or C4) positive terminal
and the negative (−) terminal to the output capacitor (C3 or C4)
negative terminal.
POWER ON THE EVALUATION BOARD
When the power source and load are connected to the ADP2300/
ADP2301 evaluation board, they can be powered up for operation.
If the input power source voltage goes higher than 7.8 V with
Jumper J5 open, the output voltage goes up to 3.3 V.
MEASURING EVALUATION BOARD PERFORMANCE
Measuring the Switching Waveform
To observe the switching waveform with an oscilloscope, place
the oscilloscope probe tip at the end of inductor connected to
the SW pin with the probe ground at GND. Set the scope to dc,
5 V/division, and 1 μs/division time base. The switching waveform
should alternate between 0 V and approximately the input voltage.
Measuring Load Regulation
Load regulation should be tested by increasing the load current
at the output and measuring the output voltage across the output
capacitor (C3 or C4).
Measuring Line Regulation
Vary the input voltage and measure the output voltage at a fixed
output current. The input voltage can be measured across the
input capacitor (C2), and the output voltage can be measured
across the output capacitor (C3 or C4).
Measuring Efficiency
The efficiency, η, is measured by comparing the input power
with the output power.
ININ
OUTOUT
IV
IV
×
×
=η
Measuring Inductor Current
The inductor current is measured by removing one end of the
inductor from the pad on the board and using a wire connected
between the pad and the inductor. Then a current probe is used
to measure the inductor current.
