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5 years, 9 months ago.
LPC1768 DAC Voltage Reference
Is there anyway to alter the DAC voltage reference on the LPC1768? I'd like to reference it to 2v.
2 Answers
5 years, 9 months ago.
Not easily, most of the mbed boards tie this directly to Vcc.
On the standard LPC1768 board you could remove L1, this feeds power from the 3.3V supply yo the ADC/DAC reference pins. You could then supply your own +2V reference voltage to the positive side of C14.
Short of cutting PCB traces there is no way to change the DAC reference voltage without changing the ADC reference.
Or you could just the values you feed to the DAC or put a divider on the output (ideally an active one so you keep the output nice and low impedance). Not ideal but easier to implement.