UG-179 Datasheet, PDF (4/12 Pages) Analog Devices – Automatic PFM/PWM mode switching

UG-179
Measuring Output Voltage Ripple
To observe the output voltage ripple, place an oscilloscope probe
across the output capacitor (C3 or C4) with the probe ground
lead at the negative (−) capacitor terminal and the probe tip at
the positive (+) capacitor terminal. Set the oscilloscope to ac,
1 mV/division, and 1 μs/division time base, 20 MHz bandwidth.
The standard oscilloscope probe has a long wire ground clip.
For high frequency measurements, this ground clip picks up
high frequency noise and injects it into the measured output
ripple. Make sure to keep the ground lengths on the
oscilloscope probe as short as possible to get a clean voltage
ripple measurement.
Evaluation Board User Guide
Varying the Output voltage
The ADP2300/ADP2301 demonstration board output is preset
to 3.3 V; however, the output voltage can be adjusted to other
output voltages using the following equation:
V_OUT
=
0.800
V × _{⎜⎜⎝⎛}1 +
R₂
R₄
⎟⎟⎠⎞
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