TDK-Lambda CPFE1000F SERIES Operation Manual - 3. Ripple And Noise
CPFE1000F SERIES
POWER SUPPLY
OPERATION MANUAL
6
5 June 2013
3. Ripple and Noise
Ripple and Noise is measured according to the description below in accordance with JEITA-9131B (Sections 7.16, 7.17
and 7.18).
The measurement connection is shown in Fig. 3-1.
(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.
In general, output ripple voltage and output spike noise voltage can be reduced by increasing external capacitance.
Fig. 3-1
Output Ripple Voltage (including Spike Noise)
Measurement Method
4. Maximum Line Regulation
Maximum line regulation is defined as the maximum output voltage change when the input voltage is gradually
changed within the specification range.
5. Maximum Load Regulation
Maximum load regulation is defined as the maximum output voltage change when output load current is gradually
changed within specification range.
6. Over Current Protection (OCP)
The CPFE1000Fxx is equipped with an OCP feature; constant current limiting. The output will enter hiccup mode when
the output current is between 105 to 140% of its output current rating. OCP value is fixed and cannot be adjusted
externally.
The power supply is also protected from a short circuit on the output. If the short circuit condition lasts longer than 15
seconds, the output voltage will recover within 20 seconds after the short is removed.