LG 37, 39 and 42 inch LCD TV power supply unit schematic – 39LN549E, 39LN575V, 39LN5300, 39LN5700-UH,
Used semiconductors: MAP3202SIRH, NR891D, SSCIS311A, MDF11N65B[FET]
On Condition: In a moment of Power ON Signal activated, the current of 3.5V output should be limited within 40mA(Max) at LCD TV condition for stability.[Do not turn “Power ON” Signal on at the load condition of 3.5V output, more than 40mA]
Total regulation for each output circuit includes the results of input voltage variation, load variation, warm-up drift and temperature change.
Maximum input Wattage Rating: Under 85W
The following instruments shall be used for measuring ripple noise.
1. Probe having impedance ratio of 1:1.
2. Oscilloscope having frequency characteristic of 100MHz or more.
Ripple and noise are measured at the end of output cable which are added a 0.1uF ceramic capacitor and 47uF electrolytic capacitor.
Connector voltages
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Burn-in
More than 2 hours at 45℃(±5℃), Normal input voltage.
AC on/off must be test 1 time after burn-in.
80% Load of specification.
This Power Supply has above-mentioned protections.
Short circuit protection between different output terminals is not considered.
Trip point for over voltage indicates the operating point when the output voltage slowly increases.
The conditions of Over Current measurement
Multi output (3.5V,12V,24V) is nominal load state except an over current measurement.