A ring oscillator (ca. 500kHz) produces a square-wave signal available at UA[0]. A 3-bit R-2R DAC produces a dc voltage availabel at UA[1].
Enable the respective blocks, and enable the transmission gates to connect the block outputs to UA[0] and UA[1], respectively. The DAC voltage can be changed by setting the digital inputs accordingly.
# | Input | Output | Bidirectional |
---|---|---|---|
0 | {‘IN[2:0]’: ‘Digital input for DAC’} | {‘UA[0]’: ‘Ringo output (if TG enabled)’} | not used |
1 | {‘IN[3]’: ‘Enable TG for DAC output to UA[1]’} | {‘UA[1]’: ‘DAC output (if TG enabled’} | n/a |
2 | {‘IN[4]’: ‘Not used’} | n/a | n/a |
3 | {‘IN[5]’: ‘Enable TG for ringo output to UA[0]’} | n/a | n/a |
4 | {‘IN[6]’: ‘Enable ringo’} | n/a | n/a |
5 | {‘IN[7]’: ‘Short UA[0] and UA[1] for testing’} | n/a | n/a |
6 | n/a | n/a | n/a |
7 | n/a | n/a | n/a |