[SOLVED] PIC reset while switch off AC 220V load and Transformerless power supply

[YIM bunchhat]

.....Hello friend,

I have a problem with arc of AC 220v supply while switch off AC load. I use transformerless power supply for my PIC16F as in picture below. If no AC load, PIC16F work OK. But when work with AC load and while I switch off or plug out AC load it make my PIC16F reset. So how to solve this problem to protect my PIC16F from reset, Please my expert friend?

 

[alokdaga]

try a decoupling capacitor of 0.1 near the vcc/gnd of pic

 

[YIM bunchhat]

Yes I have but I forgot drew on the picture above I have it already but it still have problem.

 

[KlausST]

Hi,

this often is a problem when no GND plane for the ucontroller is used, and/or bad decoupling of VCC and reset.

Known as EMV/EMC problem.

Klaus

 

[sankar.m8]

What AC load are you using?

 

[YIM bunchhat]

@Klaus, now I got this problem. Is there any way to solve it? I follow this circuit from Microchip why it still have problem. www.microchip.com/downloads/en/AppNotes/00954A.pdf

- - - Updated - - -

@sankar, I use with all kind AC device such as: Fan, Lamp, TV, heater....etc

 

[alokdaga]

In my opinion it is more related to noise on AC line - decoupling and smoothing should help...

 

[YIM bunchhat]

@alokdaga, could you share me circuit decoupling that you said to me. Because I also use capacitor 10nF between Vdd and Vss too

 

[alokdaga]

try putting a 10uF or 100uF in parallal to it and check -

 

[YIM bunchhat]

I have ever tried with 1000uF but still have this problem

 

[FvM]

As already mentioned in post #4, the problem may be that you don't have a "solid" ground (plane, meshed tracks). In this case, additional bypass capacitors are useless.

I also guess that the processor has external connections that possibly carry switching transients. All external signals must be filtered and optionally voltage clamped against circuit ground.

A trivial explanation would be direct noise crosstalk to the reset input.

 

[YIM bunchhat]

@Mr.FvM, So that does my circuit cannot use right? Exactly the reason that I use transformerless because I need space for mh circuit must small and it have to plug in AC main power. So that according to your hight knowledge is there any way better than transformerless to get power supply from main AC or if no so how can I do witn my circuit to solve this trouble? Please give me schema if possibl....thank you

 

[KlausST]

Hi,
Please take a photo and share it with us.
Maybe we can then find where to put filter circuit.

Klaus

 

[YIM bunchhat]

Hi
Which whould photo you want? On the first post I already take photo and share it, please look at it, it is my circuit.

 

[KlausST]

Hi,

We need to see the real wiring, not the schematic.

Klaus

 

[YIM bunchhat]

Hi Klaus,
The picture below is the real wire.

 

[FvM]

Please take a photo and share it with us.
Maybe we can then find where to put filter circuit.

It's gonna be difficult with the present layout.

 

[YIM bunchhat]

@FvM
I just change my decoupling capacitor and add capacitor 10uF follow alokadaga, it seem work ok now there is no reset any more but problem start with bluetooth it make bluetooth device disconnect and stuck.

 

[alokdaga]

no idea.... may be you need decoupling there also near the power pins of module.

 

[KlausST]

Hi,

I can't find a ground plane where all decoupling capacitors a re connected with low impedance.
Also i can't find the power switch to control the load. Do you have a complete schematic of your application?

Klaus