Operating the 22W LYTSwitch-1 at 26W

4 posts / 0 new

Hi There,

For our application we would like to use the LYTSwitch-1 at 26W however it is rated @ 22W .
Is there anyway to overcome this limitation ?

Kind regards,

Extremely good heatsinking ...

I make a design as per RDR-290, 36V, 2.1Amp.

but I got the only 3volt output and voltage increasing by .1v till to 6Volt.

Please suggest the about problem.

rdr290_75w_36v.pdf6.53 MB

Hi dsahani,

Here's my suggestions:

1. Kindly check the BP pin voltage waveform. The BP pin voltage will tell you whether the LinkSwitch-PH is properly biased or not. The BP pin voltage should be around 6.4V DC when it's externally biased from the auxiliary winding of the transformer but since since you only have 6V at the output, the BP pin will be supplied from the Drain pin of the IC, in which case it should be around 5.9V DC.
2. If the BP pin voltage is good, then check the waveform of the voltage across Drain-to-Source of LinkSwitch-PH IC. This will tell you what is the switching state of the internal MOSFET which is causing your output to be low. Perhaps, it's in auto-restart mode. If so, you may check and adjust the value of your biasing resistor on the FB pin. Refer to Figure 5 on the Datasheet of LinkSwitch-PH to guide you on selecting proper values for your FB pin resistor.