Bracer
New Member
I’ve completed my One Chip Tricorder Project.
However, I’ve noticed some odd behaviors that might render this “solution” worthless.
I notice that the lights stop flashing after about 21 minutes.
This could be fixed “temporarily” by reversing the 0.1 microfarad capacitor pins which will kick the circuit back on for about 8 minutes.
I have done this experiment a couple of times and the time range to failure is rather consistent [is this a good thing ?]
The only way to get the circuit working again is to recharge the batteries.
I bought new rechargeable batteries to make sure they are not the problem.
I’ve replace the microcontroller three times to see if the problem is with the 16F628A chip only to find this similar behavior in all of them.
It cannot be the batteries because after the flashing circuit failed, the LEDs that are directly connected to the power supply via a resistor are still up and running. [Could this be the problem ?]
I am left with no choice but to believe that the problem is with the PIC-Chip.
There is nothing in my codes that contain a “stop working after 21 minutes” instruction.
I started out this project with the idea that a single chip driving all the LEDs will be less power consuming then a couple of 555 and 4017 chips, but having witnessed the circuit’s failure to continue after just 21 minutes [it doesn’t fade out slowly…it just “in your face” stop working] only to be back in action upon a full charge I am left with these disappointing questions that maybe some of the friends I have made here could help.
1:
Could it be that my power supply somehow damaged the chip ?
The voltage operating range of 16F628A is 2 to 5.5V…
I also notice something interesting, if one uses a particular 16F628A chip that is “accustomed” to working on a said voltage, it will no longer desire a lower voltage, a.k.a stops working.
This is very weird; it’s almost behaving like a spoilt brad, ha ha ha
2:
Is the 16F628A chip naturally power hungry ?
3:
Am I getting inferior 16F628A Chips ?
I mean…is some company duplicating it ?
Like 555 chips in the sense that they have more than one manufacture ?
Thanks.
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