Nanotimer with 12 hours duty cycle for power saving

Alex Beloff

Other Parts Discussed in Thread: SN74HC4060, SN74AUP1G08, SN74LV163A, TPL5111, MSP430FR2000

I'm still pretty new to electronics so please bear with me.

I need to make an ultra low-power circuit that should provide power to the next stage for ~12 hours and remove power for the rest 12 hours (to save battery). I found TL5xxx nano timers (TPL5111 for example) which are user for power saving. But their maximum timing interval is just 2 hours. So my understanding is the max duty cycle is 2 hours which is not enough).

Since I've never done such a thing please give me an idea on what to use for such a circuit.

Also, I need to set a starting point - at what moment the duty cycles start daily. It could be just pressing a button or pre-programming time or ...anything.

Thank you.

over 4 years ago

0 Alex Beloff over 4 years ago

Intellectual 570 points

I found SN74HC4060 binary counter and its Icc = 80uA @ 6V. I will need the circuit to work from 3.7V. So I suppose supply current will still be way higher than when using nano timers.

Another option is to use SN74LV163A binary counter and SN74AUP1G08 AND gate (to count 6 times x 2 hours). This combination supposedly would have Icc about 11uA.

Well, that's what I understand reading datasheets...

Also, can I use nano timer as clock for SN74HC4060 binary counter? In this case it would count 2 hours cycles... Is this how it works?

0 Adam Siismets over 4 years ago in reply to Alex Beloff

TI__Intellectual 950 points

Hi Alex,

You are correct that the TPL5111 has a maximum time interval of 7200 seconds. You'll need to find a way other than using a single TPL5111 to reach the 12hr duty cycle you want.

Do you have any other parts of your design chosen? Could you also elaborate more on what you intend for your circuit to do? This information can help us determine a solution.

For those two other options you posted, it would be a good idea to submit an E2E post to the Logic Forum. They should have a better understanding for those applications.

Regards,

Adam Siismets

0 Alex Beloff over 4 years ago in reply to Adam Siismets

Intellectual 570 points

Hi!

I figured a more flexible would be to use MSP430FR2000 MCU because it has RTC and can be waken up by its interrupt.

The idea is to just create a module for IoT to save power consumption of the next stage.

Yes, I did post another related question to Logic forum so I will close this one for now.

Thank you!

0 Adam Siismets over 4 years ago in reply to Alex Beloff

TI__Intellectual 950 points

Good choice, Alex. I'm glad you were able to find help and a solution that works for you.

If you did want to read a little bit more about the TPL5111 though, there are some good technical articles related to the topic of low power consumption for IoT applications.

0 Alex Beloff over 4 years ago in reply to Adam Siismets

Intellectual 570 points

No, I haven't. But the link is broken.

0 Adam Siismets over 4 years ago in reply to Alex Beloff

TI__Intellectual 950 points

Odd, does it work without the hyperlink?

https://e2e.ti.com/blogs_/b/analogwire/archive/2015/03/12/extending-battery-life-for-iot-applications

Clock & timing

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Nanotimer with 12 hours duty cycle for power saving