> On Feb 6, 2016, at 5:31 PM, Maciej W. Rozycki <[email protected]> wrote: > >> Voltage? Recharging circuits? Current sinking capacity. It's not >> always a 1:1 mapping. > > Sure, but does it really matter in a typical battery-backed-up RAM or RTC > application seen in computers? I swapped the dead original NiCd pack for > a compatible NiMH one in my DECstation 2100 some half a year ago and the > machine seems rather happy about the replacement.
It all depends on your definition of 'typical'. In most cases, a NiMH coin cell will happily replace a NiCd one. But it's not always a 1:1 mapping. It never is if 'recharge' is uttered in the sentence. You need to spend a minute looking at the circuit before declaring MH <==> NH. It's no different than when you make any other part substitution. But when you're mucking around with something that *feeds* power into a circuit, it's worth paying a bit of attention, lest surprises come along.
