RDK-138 Power Integrations, RDK-138 Datasheet - Page 21
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RDK-138
Manufacturer Part Number
RDK-138
Description
KIT REF DESIGN 1.2W PS TN FAMILY
Manufacturer
Power Integrations
Specifications of RDK-138
Mfg Application Notes
LinkSwitch-TN Design Guide, AN-37
Main Purpose
AC/DC, Non-Isolated
Outputs And Type
2, Non-Isolated
Power - Output
1.2W
Voltage - Output
12V, 5V
Current - Output
80mA, 50mA
Voltage - Input
85 ~ 265VAC
Regulator Topology
Buck
Frequency - Switching
66kHz
Board Type
Fully Populated
Utilized Ic / Part
LNK304
Product
Accessories & Kits
Lead Free Status / RoHS Status
Not applicable / Not applicable
Other names
596-1197
12-Nov-2007
RDR-138 1.2 W Non Isolated Dual Output Supply
9.5 Output Ripple Measurements
9.5.1 Ripple Measurement Technique
For DC output ripple measurements, a modified oscilloscope test probe must be utilized
in order to reduce spurious signals due to pickup. Details of the probe modification are
provided in Figure 21 and Figure 22.
The 4987BA probe adapter is affixed with two capacitors tied in parallel across the probe
tip. The capacitors include one (1) 0.1 µF/50 V ceramic type and one (1) 1.0 µF/50 V
aluminum electrolytic type. The aluminum electrolytic type capacitor is polarized, so
proper polarity across DC outputs must be maintained (see below).
Probe Ground
Probe Tip
Figure 21 – Oscilloscope Probe Prepared for Ripple Measurement. (End Cap and Ground Lead Removed)
Figure 22 – Oscilloscope Probe with Probe Master (www.probemaster.com) 4987A BNC Adapter.
(Modified with Wires for Ripple Measurement, and Two Parallel Decoupling Capacitors Added)
Power Integrations
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