- on Power Supplies
- Published in issue 7/2001 on page 0
More and more electronic devices are portable and run off batteries. It is no surprise, then, that so many flat batteries find their way into the bin — and often far too early. When a set of batteries can no longer run some device — for example, a flashgun - the cells are not necessarily completely discharged. If you put an apparently unserviceable AA-size cell into a radio-controlled clock with an LCD display it will run for months if not years. Of course not every partially discharged cell can be put in a clock. The circuit presented here lets you squeeze the last Watt-second out of your batteries, providing a bright ‘night light’ — for free!