Hey folks a friend has given me a number of workshop lamps, containing 204 led's. They work from a small switching regulator control from a 6 pin SOT23 package, which in turn controls a triac.
In the couple I have checked atm the fet is short circuit, but also the transitor acting as a 5V regulator has also failed. I am obviously concerned the SOT23 has more than likely also failed, so would like to source a replacement part.
The SOT23 does not seem to follow standard pin out of usual buck regulators and other similar I.C.'s and I am struggling to find the exact type! I have traced the circuit and worked out the Pins to have the following functions - bear in mind I might be looking at the I.C. upside down as there is no identifying mark...
pin1 = +V / EN Pin4 = +V / EN *note these two pins connect directly to the 5V reg circuit so not sure which is which!
pin2 = connected via cap to ground Pin5 = Ground
pin3 = feedback? Pin6 = output to triac
Pin3 is connected to pin of triac which then is connected to ground via low ohms resistor array.
So has anyone got any ideas as to where to look for this part. Tried searching for buck regulators, switching regulators etc. etc. but they all come out with a different pin layout i.e. supply pins being the middle pins! And most of the I.C.'s found are designed for slightly different applications...
Frustrating!
In the couple I have checked atm the fet is short circuit, but also the transitor acting as a 5V regulator has also failed. I am obviously concerned the SOT23 has more than likely also failed, so would like to source a replacement part.
The SOT23 does not seem to follow standard pin out of usual buck regulators and other similar I.C.'s and I am struggling to find the exact type! I have traced the circuit and worked out the Pins to have the following functions - bear in mind I might be looking at the I.C. upside down as there is no identifying mark...
pin1 = +V / EN Pin4 = +V / EN *note these two pins connect directly to the 5V reg circuit so not sure which is which!
pin2 = connected via cap to ground Pin5 = Ground
pin3 = feedback? Pin6 = output to triac
Pin3 is connected to pin of triac which then is connected to ground via low ohms resistor array.
So has anyone got any ideas as to where to look for this part. Tried searching for buck regulators, switching regulators etc. etc. but they all come out with a different pin layout i.e. supply pins being the middle pins! And most of the I.C.'s found are designed for slightly different applications...
Frustrating!
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