T1 controller with Low voltage battery

Even I have concluded T1 controller project, still I would like to try to expand battery life with low voltage type PIC.

As you may see my other blog, only 3V battery (CR2032) can let IC-705 to TUNE mode, so I tried to find a suitable PIC in my junk box and found 12LF1822 (Power source 1.8V - 3.6V,  30nA at sleep mode).

I suppoce this voltage is out of Spec for 705, but it still works.

I checked battery current, and it result was as below.

Connected T1-Controller-705 and switch off conditon of 705
  Previous　1076μA　　→　　New　34μA

Disconnected T1,Controller and 705 (just before sleep mode)
  Previous   29.3μA　　→　　New　4.4μA

Sleep mode (I could not measure it, so the info from the Spec sheet)
  12F683：　350nA,　　　12LF1822：　　30nA

For your reference, I attached Circuit diagram and Program. The logic of the program is not changed, but 12(L)F1822 is newer from 12F683, and its port name etc. is different, I adjusted that part. In the diagram, I changed a value of resistance that is connected to MOS FET for reducing current consumption.

ダウンロード - t1_controller_version12_201118.pdf

ダウンロード - t1_cont_for_705_ver12.txt

ダウンロード - t1_cont_for_705_ver12.x.production.hex

You can see how it works in YouTube below.

https://youtu.be/XlGSX1shtb0

There is a precaution. If you disconnect T1 and Controller while 705 is a Power On condition, the controller will make 705 to TUNE mode and the 705 will start to transmit radio signal. To avoid this kind of problems, please turn off 705 before it disconnect from T1 and/or controller.

I tried to this experiment with my set, so even if you copy this set as above, it doesn't guarantee its function. So please try it by your own risk.

Thank you for reading, and please have a great day!