Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Jacuzzi control board

Status
Not open for further replies.

2PAC Mafia

Member
Hi,

I´m trying to repair a jacuzzi control board which shows sensor fault at display. I have measured the sensors, I have tested the sensors are getting 5V from the board and checking the board I´ve seen the values are changing at pin 11 and 12 of TLC542CN (A/D converter) when I heat the sensors, after coming from a LM324. The problem is I don´t have data out at A/D. After checking the datasheet I see I need to get pulses at pin 18 (I/O clock) but I don´t have them. I also checked pin 19 (EOC) is H and pin 15 (CS-) is L.

Pin 18 from A/D is linked to pin 15 at PIC16C57C so my question now is about this clock signal, should it come from the microcontroller or should it come from the TLC542CN? I guess is a signal which should come from the PIC to the A/D...
 
The clock is from the uC, the best way to see which isnt behaving is pull the a/d converter then 'scope/probe the clock pin, if its then present then its the a/d if not its either the uC software isnt reading it or possibly the uC itself.
CS shoudl be low when the chips working.
EOC is end of conversion, if the converter is actually working you should see pulses here too.
Also you should have pulses at the data out pin too.
 
Thanks Dr pepper, I'll try to measure with the board installed at Yacht because when I connected the display to the motherboard I hadn't communication between microcontrollers. Customer told me he had sensor fault at display but I couldn't have that situation so now I don't know if the system should be complete connected to start working.
isnt behaving is pull the a/d converter t
Do you mean to open the line?
 
That made sense at the time, but isnt clear is it.

I meant unsolder the a/d chip altogther and see if there are clock pulses to the chip pads, my thinking is that if the a/d chip has failed it could be preventing the microcontroller from sending clock signals, if the micro is a pic then if the clock pin was shorted to ground or + its probably survived as they have current limit.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top