INSTRUCTION MANUAL
PFE500F
Series
TDK-Lambda
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3. Maximum Ripple and Noise
This value is measured according to the description below in accordance with JEITA-9131B(Section 7.16, 7.17
and 7.18).
In the basic connection shown in Fig. 1-1, additional connection shown in Fig. 3-1 is done for measurement.
Capacitor (Ceramic Capacitor : 2.2µF and Electrolytic Capacitor : Refer to Table 1-2) must be connected within
50mm from the output terminals. Then, connect coaxial cable with JEITA attachment across the ceramic
capacitor electrodes. Use 100MHz bandwidth oscilloscope or equivalent.
Also, note that output ripple voltage and output spike noise voltage might vary depending on the wiring pattern
of the printed circuit board.
In general, output ripple voltage and output spike noise voltage can be reduced by increasing external
capacitance.
4. Maximum Line Regulation
Maximum line regulation is defined as the maximum output voltage change when input voltage is gradually
changed (Steady-State) within specification range.
5. Maximum Load Regulation
Maximum load regulation is defined as the maximum output voltage change when output load current is
gradually changed (Steady-State) within specification range.
When using power module in dynamic load mode, audible sound could be heard from the power module or large
output voltage change might occur. Make prior evaluation thoroughly before using this power module.
6. Over Current Protection (OCP)
This module is equipped with OCP function.
OCP function operates when the output current exceeds 105% of maximum DC output current of specification.
Output will automatically recover when short circuit or overload condition is released.
OCP value is fixed and cannot be adjusted externally.
Note that continuous short circuit or overload condition more than 30s, might result in power module damage.
7. Over Voltage Protection (OVP)
This module is equipped with OVP function. This value is set between 125% to 145% of nominal output voltage.
When the OVP function activates, first cut off input line and verify that boost voltage has dropped down to 20V
or less. Then, recover output by recycling input line. In other method, reset to ON/OFF control. OVP value is
fixed and cannot be set externally.
13/21
Fig. 3-1 Output Ripple Voltage (including Spike Noise) Measurement Method
+V
-V
Oscilloscope
R
C
1.5 m 50
W
Coaxial Cable
50mm
Load
+
-
Wires must be as short as possible
JEITA
Attachment
R : 50
W
C : 4700 pF
