Swapping out a NiMh for a LiPo?

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

What the... didn't even see you used a i2c rtc in the design... I would have just did the RTC in software and omitted a chip since it doesn't even need to be that accurate.

So when the power goes out and your software RTC doesn't know what time it is when the power comes back on ... then what?

Other thing is that I probably would have added an LED that blinks while it's self-testing. Then the user wouldn't wonder why the light was on unexpectedly...

The light has an LED that indicates when it's getting power from main ... so when the lights are on and that LED is off ... yet their TV is still on ... probably a good indication that we're refreshing the battery ....

[eccerr0r]

Re: Swapping out a NiMh for a LiPo?

So when the power goes out and your software RTC doesn't know what time it is when the power comes back on ... then what?

A, isn't that what the battery is for? You have two batteries after all!
and B, does it really matter?

The light has an LED that indicates when it's getting power from main ... so when the lights are on and that LED is off ... yet their TV is still on ... probably a good indication that we're refreshing the battery ....

As long as it's clear, but this does not seem very clear. Then again for personal use it doesn't matter though.

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

A, isn't that what the battery is for? You have two batteries after all!
and B, does it really matter?

I was talking about YOUR design where you said you would have skipped the RTC chip and just implemented the RTC in software ... you usually can't battery back the microcontroller, but the RTC chips are designed for that.

And NO, I only have ONE battery.

And YES, it does matter, because I want the circuit to discharge the battery when the day starts so that it can discharge, then charge and be ready to go by sundown ... as opposed to the unit discharging the battery at 6 pm then when the power goes out at midnight, I have no lights because my SOFTWARE RTC forgot what friggin time it was when the power went out...

Why in the world would you invest all that time writing a software RTC when you get the chips for a couple of bucks?

[eccerr0r]

Re: Swapping out a NiMh for a LiPo?

You have two batteries: the CR2032 and ... the Li-ion pack!

Up to you. Your money. Could have made the board smaller, less components, and thus cheaper... BTW yes this is depending on a low power microcontroller like the atmels, attiny, etc.

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

You have two batteries: the CR2032 and ... the Li-ion pack!

Up to you. Your money. Could have made the board smaller, less components, and thus cheaper... BTW yes this is depending on a low power microcontroller like the atmels, attiny, etc.

There is no "LiIon Pack" The light itself is runs from a NiMh pack when AC is removed from the light ... maybe this will help ...

[eccerr0r]

Re: Swapping out a NiMh for a LiPo?

"wonderful" design...

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

"wonderful" design...

It works

[eccerr0r]

Re: Swapping out a NiMh for a LiPo?

and it still needs an external device to set the time...

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

and it still needs an external device to set the time...

Are you intentionally being obtuse?

[eccerr0r]

Re: Swapping out a NiMh for a LiPo?

Are you intentionally thinking your design is the world's next unicorn product?

BTW this topic has gone off topic...where's the LiPo... I think we're done.

[sam_sam_sam]

Re: Swapping out a NiMh for a LiPo?

And YES, it does matter, because I want the circuit to discharge the battery when the day starts so that it can discharge, then charge and be ready to go by sundown ... as opposed to the unit discharging the battery at 6 pm then when the power goes out at midnight, I have no lights because my SOFTWARE RTC forgot what friggin time it was when the power went out...

Why in the world would you invest all that time writing a software RTC when you get the chips for a couple of bucks?

You do not need a time keeping chip if you just a photo cell and if there is daylight then do it program and when dark then a different part of the program it does not have to difficult to unless you want to do something different

[brethin]

Re: Swapping out a NiMh for a LiPo?

He never does things the simple way

[EasyGoing1]

Re: Swapping out a NiMh for a LiPo?

You do not need a time keeping chip if you just a photo cell and if there is daylight then do it program and when dark then a different part of the program it does not have to difficult to unless you want to do something different

He never does things the simple way

My design refreshes the battery exactly once every six weeks. Power interruptions will not change the schedule, and the location of this light is in a hallway where it's fairly dark all the time ... but I wouldn't even consider doing this without an RTC chip ... I don't see what the big deal is ... trying to do something with accuracy and reliability ...

As far as cost goes, this was a personal project ... I'm not trying to market the thing .. I had fun doing it, so the cost was irrelevant.