Hi
As a newbie, my appologies if I’ve posed this Q in the wrong topic area.
I’ve been playing around with the pre-assembled board. But I’ve noticed that the DAC O/P voltage (1 & 2) only reach around 4.65V (for a DAC I/P of 255).
I’ve checked the voltage coming out of the PIC (RC1 & RC2) & it’s only about 4.69V.
Any ideas ?
Regards
Bill
The output voltage is proportional to the USB supply voltage. As you noted the microcontroller outputs are about 0.3V lower than the USB supply. This voltage loss is normal.
If you need higher voltage then one solution may be to use a self powered USB HUB.
I made a test:
Without HUB:
USB supply voltage: 5.09V
DAC output voltage: 4.70V
With HUB:
USB supply voltage: 5.15V
DAC output voltage: 4.76V
Hi Vel266 - Many thanks for such a prompt reply. That clarifies things for me; I though my board was plyaing up. I didn’t realise the relationship to the USB level, suppose I should have done.
Many Thanks
Bill