A giant, configurable ring oscillator with up to 3853 stages. To enable the ring oscillator, connect one of the output pins to the first input pin (ring_in
/ ui_in[0]
). Each output pin is connected at a different point in the ring oscillator chain, making it possible to create rings of different lengths:
Pin | Chain length |
---|---|
uo[0] | 1 |
uo[1] | 3 |
uo[2] | 5 |
uo[3] | 7 |
uo[4] | 11 |
uo[5] | 21 |
uo[6] | 51 |
uo[7] | 101 |
uio[0] | 201 |
uio[1] | 501 |
uio[2] | 1001 |
uio[3] | 2001 |
uio[4] | 3001 |
uio[5] | 3853 |
Connect one of the output pins (e.g. uio_out[5]
) to ring_in
, and measure the output frequency.
A scope / logic analyzer to measure the output frequency and the delay between different points in the inverter chain.
# | Input | Output | Bidirectional |
---|---|---|---|
0 | ring_in | len1 | len201 |
1 | len3 | len501 | |
2 | len5 | len1001 | |
3 | len7 | len2001 | |
4 | len11 | len3001 | |
5 | len21 | len3853 | |
6 | len51 | ||
7 | len101 |