RDK-91 Power Integrations, RDK-91 Datasheet - Page 24

• Manufacturer Part Number: RDK-91
• Description: KIT DESIGN REF TINYSWITCH-III
• Manufacturer: Power Integrations
• Series: TinySwitch®-IIIr

Specifications of RDK-91

• Main Purpose: AC/DC, Primary Side
• Outputs And Type: 1, Non-Isolated
• Power - Output: 12W
• Voltage - Output: 12V
• Current - Output: 1A
• Voltage - Input: 85 ~ 265VAC
• Regulator Topology: Flyback
• Board Type: Fully Populated
• Utilized Ic / Part: TNY274, TNY275, TNY276, TNY277, TNY278, TNY279, TNY280
• Product: Accessories & Kits
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Frequency - Switching: -
• Other names: 596-1194

10 Thermal Performance
Temperature measurements of key components were taken using T-type thermocouples.
The thermocouples were soldered directly to a SOURCE pin of the TNY278PN device
and to the cathode of the output rectifier. The thermocouples were glued to the output
capacitor and to the external core and winding surfaces of transformer T1.
The unit was sealed inside a large box to eliminate any air currents. The box was placed
inside a thermal chamber. The ambient temperature within the large box was raised to
50 °C. The unit was then operated at full load and the temperature measurements were
taken after they stabilized for 1 hour at 50 °C.
These results show that all key components have an acceptable rise in temperature.
Figure 11 – Infrared Thermograph of Open Frame Operation, at Room Temperature.
Power Integrations
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www.powerint.com
85 VAC, 12 W Load, 22 °C Ambient
*To simulate operation inside sealed enclosure at 40 °C external ambient.
Ambient
TNY278PNP (U1)
Transformer (T1)
Output Rectifier (D7)
Output Capacitor (C10)
Item
Temperature (°C)
85 VAC
96.1
77.8
68.2
101
50
*
265 VAC
92.8
66.8
100
50
80
*
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