Aldi/Ferrex finale (Patreon)

ALDI/Ferrex PCB trilogy finale

And finally the 20V tool PCB for the 20/40V battery pack system. This shares the same complex power management system as the others for ultra low standby current. It's quite perplexing. I think two of the inputs are analogue for voltage monitoring. An unexpected feature of this module is that it doesn't control the tool directly, but just sits between it and the battery. When the tool is used this module detects the load, wakes up and switches on the MOSFETs to allow the tool to be powered fully. The bulk of the circuitry is to allow the module to sleep when not needed. If woken, the unit remains awake while the load is present, but quickly shuts down into a sleep mode again. During sleep the processor is powered down completely and other sections of circuitry are also deactivated. Although you can trick the tool into running by putting a 10K resistor between negative and the central thermistor contact, it will lose the ability to sense if a non-compatible battery pack is low, so may over discharge the pack if it doesn't have its own internal under-voltage shutoff. Mid-play video-adverts are annoying in technical videos, so I don't enable them. If you appreciate that and enjoy my content then you can help support the channel with a contribution of a dollar or two a month on Patreon. That also lets you critique the (advert free) videos before they are released, gives a more direct means of communication with me and also gives access to the regular relaxed Patreon live streams. https://www.patreon.com/bigclive #ElectronicsCreators