Revitalising a Sun Jar and the Joule Thief Revisited
As Figure 2 shows there is a small surface mount chip on the PCB. I looked this up online and finally tracked down the 6603 marking to being a dedicated solar garden light chip. However it also appears to be obsolete, so simply de-soldering this and replacing it with a new one was not an option.
Fortunately, whilst searching, I came across what appears to be the modern day version of this chip; the QX5252, which is widely available from eBay sellers – many of which are in China and remarkably cheap (prices from less than £1 for one to even less in bulk; yes, it wascheaper to buy in bulk!). Figure 3 shows the QX5252F device and a standard circuit from the datasheet.
Even a cursory comparison of the PCB in Figure 2 and the diagram in Figure 3 makes it clear that the newer component requires far fewer additional components to make the solar lampcircuit. It was clear, that if I was going to bring my sun jar back to life, I was going to have to create a new circuit around the new solar component.