CPFE1000FI SERIES
POWER SUPPLY
OPERATION MANUAL
5
19 August 2020
Fig. 2-1 Output Voltage Adjustment
by applying external voltage
Note: The Trim terminal voltage must be limited to 1.00V maximum; otherwise, the over-voltage protection circuit will
activate and shut down the output voltage.
3. Ripple and Noise
Ripple and Noise is measured according to the description below in accordance with JEITA RC-9131C (Sections 7.16,
7.17 and 7.18).
The measurement connection is shown in Fig. 3-1.
C1 (0.1µF Ceramic Capacitor), C2 (47uF Aluminum Electrolytic Capacitor) must be connected in parallel at 30cm from
the output terminals, along the load cable. Attach a maximum 1.5m 50Ω coaxial cable from the ceramic capacitor
electrodes to a filter attachment installed on the oscilloscope. The filter attachment consists of C3 (4700pF film capacitor)
in series with R (50Ω resistor). Use 100MHz bandwidth oscilloscope or equivalent.
In general, output ripple voltage and output spike noise voltage can be reduced by increasing external capacitance.
Model
Adjustment Range
Typical External Voltage Range
CPFE1000FI-12
9.6 – 14.4V
0.65 – 1.0V
CPFE1000FI-28
22.4 – 33.6V
0.65 – 1.0V
CPFE1000FI-48
38.4 – 57.6V
0.67 – 1.0V
+S
-S
+V
-V
TRIM
+
-
Load
