Analog shield DAC for galvo

[mitchpitch]

Is the analog shield's DAC range from -5V to 5V? My purpose is to use the shield for driving the x/y mirrors of a laser galvo.

And is there information about the update frequency of the write function?

Thanks in advance!

[jpeyron]

Hi @mitchpitch,

Here is a forum discussing the DAC range. It has a 4 Channel 16 bit 100 ks/s string DAC. The write function depends on the arduino default spi funtions as shown by the write function in the analogShield.cpp. 

thank you,

Jon

[mitchpitch]

Thanks. I saw that, too. But i was confused about the moderator's statement. He wrote about a range from 0-5V.

In the source code i found this description in the write() function

unsigned int value0 - Raw value from 0 to 65535

unsigned int value0 - Raw value from 0 to 65535 
corresponding to -5V - 5V 

 

[JColvin]

Hello @mitchpitch,

My comment was incorrect; I'll change it. The part always has an adc read of 16 bits from -5 to +5 volts. The only difference is if you choose the 16 bits to be represented as 0 to 65535 or from -32768 to 32767. The DACs also output from -5V to +5V.

Let me know if you have any questions about this.

Thanks,
JColvin