18-12-2016, 10:18 AM
That's a complicated method, Nick 
If you don't have a schematic, then the easiest thing to do is use a bench PSU set to just below the value of the battery. Perhaps via a 1k "safety" resistor if worried. OK, there are exceptions, but the vast majority of bench power supplies are series regulators that only sink current, so they won't attempt to charge or discharge the battery in that state.
Here we have a schematic. So here, I'd just connect a ~5V PSU to "MEM PWR" - across C16 - as D4 prevents the battery from being charged. Simple
One minor concern with the 4700uF capacitor: the amount of instantaneous current that could flow somewhere it shouldn't... Sure it wouldn't hurt the battery, but I'd be tempted to use a safety resistor in series with it.
If you don't have a schematic, then the easiest thing to do is use a bench PSU set to just below the value of the battery. Perhaps via a 1k "safety" resistor if worried. OK, there are exceptions, but the vast majority of bench power supplies are series regulators that only sink current, so they won't attempt to charge or discharge the battery in that state.
Here we have a schematic. So here, I'd just connect a ~5V PSU to "MEM PWR" - across C16 - as D4 prevents the battery from being charged. Simple
One minor concern with the 4700uF capacitor: the amount of instantaneous current that could flow somewhere it shouldn't... Sure it wouldn't hurt the battery, but I'd be tempted to use a safety resistor in series with it.
