78L05:
I'll check to see what the total current is in my 5v circuit. That circuit powers the two 5mm LEDs (28mA), the ATTINY and the PIR sensor. I should be well under 100mA. I'll pick up some 1uF SMD caps for the Vout side and will use my 10uF SMD caps on the Vin side. Thx for the suggestion and confirmation for making this change!! And, thx to Eric for working so diligently on the hysteresis Arduino code!
We're almost there I believe.

 

hj john,
This the LDR << ADC count plot for this morning, looks OK to me,
E
BTW: ref the 78L05 regulator.
You are dropping from 12V to 5V at say 0.1A, that is 7V*0.1A= 0.7 Watts, check the 78L05 datasheet for its specified power limit.

 

That circuit powers the two 5mm LEDs (28mA), the ATTINY and the PIR sensor

Actually the two LEDs are on the 12 volt supply so it's just the PIR and ATtiny

 

hj john,
This the LDR << ADC count plot for this morning, looks OK to me,
E
BTW: ref the 78L05 regulator.
You are dropping from 12V to 5V at say 0.1A, that is 7V*0.1A= 0.7 Watts, check the 78L05 datasheet for its specified power limit.


View attachment 362032View attachment 362033

That's great!! Those results look ideal... I can't wait to test it on the attiny. I assume that adjusting the light/dark levels will be easy enough for me to address in the code if needed. I'll study the coding closely so I can better understand exactly what it is doing. And yes, I will check the power limit on the 78L05.
Thx again!!

 

Actually the two LEDs are on the 12 volt supply so it's just the PIR and ATtiny

Of course... I had a brain fart... LOL
Thank you for correcting me on that.

 

The 78L05 will actually be dissipating only .2 watts after sghioto pointing out my misstatement about the two 5mm LEDs being on that 5v circuit. Those are actually on the 12v circuit. It looks like the 78L05 can dissipate .5 watts, so we're good to go!!!

 

I estimate it's under 50mw.

 

I estimate it's under 50mw.

I meant .02 watts. Thx

 

Can an LM78L05 be used with my SI2321 in my reverse polarity protection circuit to replace the zener and resistor. If I can get rid of that microscopic zener, I'll be happy. This was in the datasheet (attached)

 

Can an LM78L05 be used with my SI2321 in my reverse polarity protection circuit to replace the zener and resistor. This was in the datasheet (attached)
View attachment 362057
View attachment 362059
View attachment 362060

No. The zener will begin zener action at 6.8v, 5ma and prevent over voltage to the mosfet gate.

 

No. The zener will begin zener action at 6.8v, 5ma and prevent over voltage to the mosfet gate.

Ok. Is there any zener that is larger in footprint in SMD? Or, maybe recommend a through hole. I have a few through holes to solder anyway.

 

This might be easier for me to solder to the board. I'll be using a stencil, solder paste and hot plate for the SMDs and will hand solder the through hole components:
BZX55C6V8

 

I'm hoping this is the finished schematic with PCB image (schematic file attached). Please let me know if you have any additional comments. Thx!

 

Are C1 and C2 still 100uf?

 

Are C1 and C2 still 100uf?

Yes. Is that a mistake?

 

Don't see the need for either cap as the circuit is battery powered.
C4 and C5 are sufficient.

 

This might be easier for me to solder to the board. I'll be using a stencil, solder paste and hot plate for the SMDs and will hand solder the through hole components:
BZX55C6V8

That will work.

 

Don't see the need for either cap as the circuit is battery powered.
C4 and C5 are sufficient.

As long as there is no battery charger or EMI.

 

As long as there is no battery charger or EMI.

The battery is external and charged by solar panel and controller. There should be no EMI.
I will delete C1 and C2. Thx guys

 

The battery is external and charged by solar panel and controller. There should be no EMI.
I will delete C1 and C2. Thx guys

A solar charger generates ripple, so I suggest leaving in at least C1 (the one closest to the RVP mosfet).