EVAL-ADP1712/ADP1713/ADP1714

Rev. 0 | Page 5 of 8

OUTPUT VOLTAGE MEASUREMENTS

GND

GND

GND

GND

C1

C2

U1

C3

R1

R2

VIN

VOUT

EN

J1

EVAL-ADP1712/

ADP1713/ADP1714

SS/ADJ/BYP/TRK

+

_

VOLTAGE SOURCE

+

_

VOLTMETER

V

LOAD

Figure 7. Output Voltage Measurement

Figure 7 shows how the evaluation board can be connected to

a voltage source and a voltage meter for basic output voltage

accuracy 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 also be used as an alternative. Ensure

that the voltage source can supply enough current for the

expected load levels.

Follow these steps to connect to a voltage source and voltage meter:

1.

Connect the negative terminal (−) of the voltage source to

one of the GND pads on the evaluation board.

2.

Connect the positive terminal (+) of the voltage source to

the VIN pad of the evaluation board.

3.

Connect a load between the VOUT pad and one of the

GND pads.

4.

Connect the negative terminal (−) of the voltage meter to

one of the GND pads, and the positive terminal (+) of the

voltage meter to the VOUT pad.

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.

If the load current is large, the user needs to connect the voltage

meter as close as possible to the output capacitor to reduce the

effects of IR drops.

LINE REGULATION

For line regulation measurements, the regulator’s output is

monitored while its input is varied. For good line regulation,

the output must change as little as possible with varying input

levels. To ensure the device is not in dropout during this

an ADP1712 with fixed 3.3 V output, VIN needs to be varied

between 3.8 V and 5.5 V. This measurement can be repeated

under different load conditions. Figure 8 shows the typical line

regulation performance of an ADP1712 with fixed 3.3 V output.

3.280

3.285

3.290

3.295

3.300

3.305

5.3

3.3

3.8

4.3

4.8

Figure 8. Output Voltage vs. Input Voltage