ADP2102-1.875EVALZ Analog Devices Inc, ADP2102-1.875EVALZ Datasheet - Page 3

• Manufacturer Part Number: ADP2102-1.875EVALZ
• Description: BOARD EVAL FOR ADP2102-1.875
• Manufacturer: Analog Devices Inc

Specifications of ADP2102-1.875EVALZ

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 1.875V
• Current - Output: 600mA
• Voltage - Input: 2.7 ~ 5.5V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: ADP2102
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Frequency - Switching: -

EVALUATION BOARD HARDWARE
POWERING UP THE EVALUATION BOARD
The ADP2102 evaluation boards are supplied fully assembled
and tested. Before applying power to the evaluation board,
follow the procedures in this section.
Jumper JP2
Before turning on the ADP2102 evaluation board, make sure
that all the components are present, but that Jumper JP2 is
removed. Jumper JP2 enables the part.
Jumper JP1
The ADP2102 can be configured to operate in low noise
continuous conduction mode (CCM) or in power-save mode
(PSM), depending on the MODE pin polarity. If the MODE pin
is pulled high, ADP2102 operates in forced continuous conduction
mode, and if the MODE pin is pulled low, ADP2102 operates in
power-save mode.
Input Power Source
Before connecting the power source to the ADP2102 evaluation
board, make sure it 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 on the evaluation board, and the negative terminal of
the power source to the GND terminal of the evaluation 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 lead (+) of the power source to the ammeter positive (+)
connection, the negative lead (−) of the power source to the GND
terminal on the evaluation board, and the negative lead (−) of the
ammeter to the VIN terminal on the board.
Output Load
Although the ADP2102 evaluation board can sustain the sudden
connection of the load, it is possible to damage the load if it is not
properly connected. Make sure the board is turned off before con-
necting the load. If the load includes an ammeter, or if the current
is not measured, connect the load directly to the evaluation board,
with the positive (+) load connection to the VOUT terminal and
negative (−) load connection to the GND terminal. If an ammeter
is used, connect it in series with the load: connect the positive (+)
ammeter terminal to the evaluation board VOUT terminal, the
negative (−) ammeter terminal to the positive (+) load terminal,
and the negative (−) load terminal to the evaluation board GND
terminal.
Once the load is connected, make sure it is set to the proper
current before powering the ADP2102 evaluation board.
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Input and Output Voltmeters
Measure the input and output voltages with voltmeters. Make
sure that the voltmeters are connected to the appropriate
evaluation board terminals and not to the load or power source
themselves. If the voltmeters are not connected directly to the
evaluation board, the measured voltages would be incorrect due
to the voltage drop across the leads and/or connections between
the evaluation board, the power source, and/or the load.
Connect the input voltage measuring voltmeter positive termi-
nal (+) to the evaluation board VIN terminal, and the negative
(−) terminal to the evaluation board GND terminal. Connect
the output voltage measuring voltmeter positive (+) terminal
to the evaluation board VOUT terminal and the negative (−)
terminal to the evaluation board GND terminal.
Turning On the Evaluation Board
Once the power source and load are connected to the ADP2102
evaluation board, the board can be powered for operation. Slowly
increase the input power source voltage until the input voltage
exceeds the minimum input operating voltage of 2.7 V. Insert
Jumper JP2 and check to see if the output voltage rises to the regu-
lated output voltage (for example,1.2 V for the ADP2102-1.2-
EVALZ). Ensure that the minimum input supply voltage is greater
than 4.5 V for powering up the adjustable ADP2102–4-EVALZ.
The input voltage range for the 2.5 V to 3.3 V adjustable output
voltage option is from 4.5 V < V
If the load is not already enabled, enable the load; check that it is
drawing the proper current and that the output voltage maintains
voltage regulation.
MEASURING EVALUATION BOARD PERFORMANCE
Measuring Output Voltage Ripple
To observe the output voltage ripple, place an oscilloscope
probe across the output capacitor (C2) with the probe ground
lead at the negative (−) capacitor terminal and the probe tip at
the positive (+) capacitor terminal. Set the oscilloscope to ac,
20 mV/division, and 2 μs/division time base.
Measuring the Switching Waveform
To observe the switching waveform with an oscilloscope, place
the oscilloscope probe tip at the end of the inductor that is
connected to the LX pin with the probe ground at GND. Set the
oscilloscope to dc, 2 V/division, and 2 μs/division time base.
The switching waveform must alternate between 0 V and
approximately the input voltage.
Measuring Load Regulation
The load regulation must be tested by increasing the load at the
output and looking at the change in output voltage. To mini-
mize voltage drop, use short low resistance wires, especially for
heavy loads.
IN
< 5.5 V only.
EVAL-ADP2102