Hi,
I have LPCXpresso LPC1769 Rev.D board and I need to use DAC to controll some external device.
I unsoldered L1 BK1608HS220-T from LPCXpresso LPC1769 and I connected directly my reference voltage source - REF193.
I have some troubles with LPC1769 DAC. There is no output voltage as should be.
Below is a table with results (DAC Sens = 2,9297 mV/sa = 3000 mV/1024 sa):
0 sa - 17,7 mV (should be 0 V)
5 sa - 32,5 mV (should be 14,6 mV)
10 sa - 46,7 mV (should be 29,3 mV
20 sa - 75,8 mV (should be 58,6 mV)
30 sa - 104,6 mV (should be 87,9 mV)
40 sa - 134,5 mV (should be 117,2 mV)
50 sa - 163,5 mV (should be 146,5 mV)
multimeter BRYMEN BM811A
There is a chart in attachement with my DAC voltage output values...
There is some nonlinear bias/offset.
What is wrong? Do I need something else for my DAC?
