Problems with TLC5628 DAC
msh5686
Posts: 70
Hi Everyone,
I'm testing a TLC5628 DAC that I need to use for a larger project. My issue is, no matter what value I input into the DAC, the output voltage is always 1.5 times the input voltage. Looking at the data sheet for this chip, I am a little confused with the output equation. My equation I was sending to the chip you can see is commented out because I wanted to see if there would be a difference by just sending a 12 bit stream, 3 for addressing, 1 for the optional amplifier, and the last 8 being the number I want to send out from the DAC. As you can see, in this case I am sending the binary number 128 to the DAC, but the analog I get out is 1.88. Can anyone enlighten me as to my mistake? As always, thanks for the help!
TLC5628.bs2
I'm testing a TLC5628 DAC that I need to use for a larger project. My issue is, no matter what value I input into the DAC, the output voltage is always 1.5 times the input voltage. Looking at the data sheet for this chip, I am a little confused with the output equation. My equation I was sending to the chip you can see is commented out because I wanted to see if there would be a difference by just sending a 12 bit stream, 3 for addressing, 1 for the optional amplifier, and the last 8 being the number I want to send out from the DAC. As you can see, in this case I am sending the binary number 128 to the DAC, but the analog I get out is 1.88. Can anyone enlighten me as to my mistake? As always, thanks for the help!
TLC5628.bs2
bs2
580B
Comments
I realized I had the reference voltage too high. Now I have it turned down to 2.5 volts and when I send a full value to the DAC get 255 Back. Now I'm just having trouble with the addressing. The fourth bit sent is supposed to be a trigger for an p amp inside the DAC with a gain of 2 to be used. The problem I'm having is when I activate this bit, the outage does not change. Any advice would be appreciated!