8055 No Analog power on output

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1

Hi Guys, I have a 8055 board and I was planning to connect it to a temperature sensor but when I attempted to turn the analog power on it didnt work. I clicked set all analog channels and the leds didnt even come on. This was a pre built board so there shouldnt be a problem in the soldering. Ive checked and everything else is okay power to the digital outputs and even the analog input picks up voltage oway

Any Help ? Thanks in advance

2

This is very strange.

  • All digital outputs work: You can set the LEDs LD1…LD8 on and off.
  • All digital inputs work: You can see this in the user interface (Inputs check boxes) by pressing the test buttons Inp1…Inp5.
  • Analog input works: You can see the movement of the AD1 and AD2 bars when you adjust the trimmers ATT1 and ATT2 in test mode. (Jumpers SK2 and SK3 placed.)
  • But - You can’t get the LEDs LD9 and LD10 lit when moving the sliders DA1 and DA2 or pressing “Set All Analog” button?

If this is the case there have to be something strange in the analog (PWM) output section of the board…

3

Yep, checked it all, only the analog outputs dont work. I ran a multimeter over the connections to check for a link through the resistors. no faults found in any resitors so i can only assume its one of the chips.

Also checked tried a different power cable in case there was a fault in supplying the full power to the board.

4

Next you may check the voltage on pins 12 and 13 of IC3 (against GND).
Adjust the analog outputs and look the voltages. - What values you get?

5

0.0 to 0.3 when both are on. Might have found the fault

6

Seems faulty.
Should be about 4.7V when the analog outputs are on.