SMD Led Based Rechargable Chinese Led Lamp Repair
This is a chinese made SMD led based rechargeable lamp. The problem was that the battery was not charging. I opened up the circuit and found a transfromerless power supply used to charge the battery. The Circuit has a x-rated capacitor, 4 diodes to produce DC.
I powered on the device and checked for DC voltage and there was no voltage. I then suspected some issue with the rectification section build around 4 IN4007 diodes. I checked all the 4 by desoldering them from the PCB and found one to be open circuited which offered a very high resistance.
I replaced the diode with a new one. I powered on the circuit and was glad to find DC output from the bridge section. I then kept the power on for 30 mins which charged the battery and finally the lamp was brought back into life.
Take utmost care while working with AC voltage !!
In case if you have any doubt/ suggestions/ query, please leave them on the comments section below.
Tags: smd led