INSTRUCTION MANUAL
PFE500F
Series
TDK-Lambda
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C17 : Refer to Table 1-2
Connect C17 within 50mm from the output terV and -V of the power module to stabilize operation and
to reduce output ripple noise voltage.
Note that the output ripple and line turn off characteristics of the power module might be affected by the ESR
and ESL of the electrolytic capacitor.
Also, note that output ripple voltage might vary depending on the wiring pattern of the printed circuit board.
Fluctuation in output voltage due to sudden load change or sudden input voltage change can be reduced by
increasing external output capacitor value.
Note) 1. Use low-impedance electrolytic capacitors with excellent temperature characteristics.
(Nippon
Chemi-con
LXY Series or equivalent)
(Nichicon PM Series or equivalent)
2. For module operation at ambient temperature -20 deg C or less, output ripple voltage might be affected
by ESR characteristics of the electrolytic capacitors. Increase the capacitor values shown in Table 1-1
and 1-2 according to the table below.
3. Take note of the allowable maximum ripple current of the electrolytic capacitor used. Especially,
for sudden load current changes, verify actual ripple current and make sure that allowable maximum
ripple current is not exceeded.
9/21
12V
Vout
25V 1,000uF
C17
28V
50V 470uF
48V
100V 220uF
Table 1-2 C17:Recommended external capacitance
12V
Vout
25V 1,000uF x 2 parallel
C15 , C17
28V
50V 470uF x 2 parallel
48V
100V 220uF x 2 parallel
Table 1-3 C15, C17 : Recommended external capacitance (Ambient Temperature < -20 deg C)
