please help me with my problem about mcu

[crabking]

whats wrong with my project...i created 5v regulator supply connected to pic16f84a and then if i connect it to pic16f84a, the voltage regulator produce heat as well as the mcu..and if i disconnect the regulator from mcu...the regulator doesnt release heat...it is possible that my mcu has defect?

 

[ckshivaram]

the IC is getting loaded.. check if supply and gnd are not shorted... or IC has gone bad...

 

[malik_zohaib]

Agree..
Seems short to me. Check your ps, and ucontroller vcc and vss pins.

 

[bigdogguru]

Could you have reversed the polarity on the VSS and VCC pins?

 

[crabking]

thanks to all..but i checked already the vss and vdd if they are shorted...they are not shorted...i check again the temperature of mcu and still hot...

---------- Post added at 06:31 ---------- Previous post was at 06:23 ----------

please check this circuit and code if it is correct

check this image of my circuit:


here is the code:
clear
ti var byte
c var byte
z var byte
ti=100
trisb=0

open:
for z=1 to 2
portb=128
pause ti
portb=64
pause ti
portb=32
pause ti
portb=16
pause ti
next z
goto delay

open1:
for z=1 to 2
portb=128
pause ti
portb=64
pause ti
portb=32
pause ti
portb=16
pause ti
next z
goto delay3

close:
for z=1 to 2
portb=16
pause ti
portb=32
pause ti
portb=64
pause ti
portb=128
pause ti
next z
goto delay1

close1:
for z=1 to 3
portb=16
pause ti
portb=32
pause ti
portb=64
pause ti
portb=128
pause ti
next z
goto delay4

delay:
portb=0
pause 2000
goto close

delay1:
portb=0
pause 2000
goto loop
delay2:
portb=0
pause 2000
goto open1

delay3:
portb=0
pause 2000
goto close1

delay4:
portb=0
pause 2000
goto loop1
delay5:
portb=0
pause 2000
goto open

loop:
for c=0 to 11
portb=8
pause ti
portb=4
pause ti
portb=2
pause ti
portb=1
pause ti
next c
pause 2000
goto delay2

loop1:
for c=0 to 11
portb=1
pause ti
portb=2
pause ti
portb=4
pause ti
portb=8
pause ti
next c
goto delay5
end

 

[prmurthy]

Topic changed. Let us discuss on the first problem. Please tell us wheather you are feeding the power from battery or transformer. If it is through thransformer please confirm that your using a bridge to rectify the voltage. If all above yes then please check your 5V regulator it is faulty, provided that your poliraty is correct.
Thankyou

 

[crabking]

thank you..i use an multi purpose adapter..it is ok to use this kind of supply to connect to the voltage regulator circuit?

 

[prmurthy]

PLEASE REMEMBER THAT MULTI PURPOSE ADAPTERS DELIVER MORE VOLTAGE THAN REQUIRED. IF YOU SELECT 5v IT WILL DELIVER NEARLY 7V THIS IS WHY YOUR MCU IS HEATING.

Please change the voltage to something like 3 or 4.5v and measure the output voltage it should be <= 5V for MCU.

Thankyou

 

[crabking]

thank you very much for your help...

i already check the output voltage of the voltage regulator circuit..it give 5.01v but still the mcu is heating...i dont know why.

 

[prmurthy]

Use of bridge or use of 220uF 16V capacitor for input side and 10uF 16V is required in your case.

Thankyou

 

[crabking]

thank you very much..i used 470uf in the input side and 4.7uf in the output side...i will try 220uf and 10uf

 

[prmurthy]

I am 100% sure of only 2 problems.

1. Your adapter polarity is having some problem.
2. your regulator is having problem.

Alternate best fail-safe solution is use 4 1.5V AA battery without 7805 and power it to MCU. If this works then you MCU is safe and above are the only problems. But I would like to see some kind of diagram of your actaul setup other than what you showed above.

Thankyou

---------- Post added at 07:03 ---------- Previous post was at 07:02 ----------

sorry make it 3 1.5V AA cells

 

[crabking]

i have here 6 battery which is equivalent to 6v...

if the mcu is still heating..it is possible that the mcu is already damage?

 

[prmurthy]

Don't use 6V the MCU requires only 5v so use only 3 to make 4.5V. If still heats then it is MCU problem. The heat should be more than room temperature to conclude the MCU problem. I am sure the mcu cannot go bad unless you have given more than 5V to MCU.

Thankyou

 

[ckshivaram]

remove all the ICs from the board and see the VCC in the 40 Pin IC base for controller...
then put the controller without any other ICs and check the VCC and see if it gets heated.. if still it gets heated then IC is gone... if not insert other ICs one by one and find out when it gets heated , and find the fault....

 

[crabking]

thank you very much...

 

[ckshivaram]

long use of 6V damages the controller.. change the controller and give 5V if you dont have regulator....

 

[prmurthy]

Hi Sir(Shivaram)

We really don't know how his setup is. Hence I requested him to put his setup so that we can solve the problem in just one post.

Thankyou

 

[crabking]

thank you for your help and guide...

---------- Post added at 07:21 ---------- Previous post was at 07:19 ----------

i can i post the setup?the circuit design only or i will take picture of my actual design?

 

[prmurthy]

Either schematic drawing or picture any thing will do as long as it is clear.

Thankyou