LMC555: How to lessen current consumption?

ArTzy

Mastermind 19920 points

Part Number: LMC555
Other Parts Discussed in Thread: TPL5110-Q1, TPL5110

Tool/software:

Hi Experts,

I have attached the schematic and list of components:

I have not been able to do an actual test to see how much current it is drawing; it is very difficult. The circuit is integrated on a flex board that wraps around a 3v battery such as a cr2032. The components are very small, and the height of the chip components is max 1mm. so it can fit in a remove together with the battery. The battery and circuit go inside a remote control that is normally constantly transmitting. The purpose of the circuit is to shut the power from the battery to the remote when the remote is stationary for 8 seconds. Once the remote is picked up or any vibration the circuit will resume power to the remote. As long as the remote continues to be in motion the power for the remote will be active.

Let me know if you think I can somehow reduce the current to be in the teens. From the data sheet it shows 130uA current draw for the 555 timer; the battery is 220mAH. That would give approximately 60 days of battery use. If it was at 15uA, then the battery would last approximately 600 days which would be great.

I have 2 circuits that were in the remotes and after 2 months would not transmit because the battery is too low. It was a brand-new battery when I installed them.

For your assistance.

Regards,
Allan

over 1 year ago

0 Ron Michallick over 1 year ago

TI__Guru**** 171046 points

Hello Allen,

For 8 seconds delay and battery optimization, I suggest TPL5110-Q1. Typical current is 35nA

For help with this timer, click the (orange) ask a related question button, and use TPL5110-Q1 as a part number.

0 Allan Balgley over 1 year ago in reply to Ron Michallick

Prodigy 180 points

Hi Ron,

Thank you very much for your recommendation. I will try it. Will this chip work without a microcontroller? I am concerned I don't have a done signal. And it will constantly reset.

I went to this link and read the description. Its claiming 20uA and specs shows 35nA. Why the difference?

www.adafruit.com/.../3435

Thanks again Ron

0 Ron Michallick over 1 year ago in reply to Allan Balgley

TI__Guru**** 171046 points

Allan,

Here is the whole portfolio. Ask a related question (orange button near top of page) using one of these part numbers to get expert advice on these products that are not in my direct group.

Under the part numbers above, they can help you generate an automatic DONE signal or point you to a more appropriate part number. TPL5110 does use more current at power up to test the timing setting resistor, this is a one and done current.