I am probably doing something wrong. Could the pump be too much for the DAC? Do you think sending a pulse through it might be better? I was thinking about this as an alternative. If I send a pulse through at an amplitude specified by the datasheet say 3Vpp bc the operating range for pump control is 0.06 v to 2.75 v. I said 5Vpp bc it would be +/-1.5 v. I would have play with the frequency to get optimal results.
I used an Adafruit MCP4725 Breakout board for my tests.
This breakout board has a 10k pulldown resistor connected to the A0 pin.
Age unknown - but that shouldn't matter.
I am using the same DAC. Maybe using the pulldown resistor would help. I agree the age shouldn't matter. What does the A0 pin do?
The pulldown resistor is fitted as standard by Adafruit. it is used to select the I2C address.
The pulldown resistor holds the A0 pin low, and so it's I2C address is 0x62.
There are a couple of pads on the back of the PCB labelled ADDR. If you connect these pads with a ball of solder the A0 pin is taken high, and the address changes to 0x63.
Ohh this knowledge would've been helpful earlier. At least I know it now. Would this help not stressing the DAC out? Or does stressing out the board stem from another issue?
Maybe, probably not. I did not see the specification that woukd definitively answer that in the pump datasheet.
But you can test the DAC, once you've confirmed or made the changes suggested above, by simply looking at the output without the pump connected.
If your code changes the values too quickly, slow it down so you might see each voltage attained as the sequence repeats. Just crank up the delay you make after each step.
a7
Sounds good, I'll let you know how it goes.
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