Chargement…
Chargement…
i_x is an 8-bit signed integer interpreted as Q4.4, so its real value is signed(i_x) / 16. o_y is an 8-bit unsigned value representing round(255 * sigmoid(x)).
The target function is sigmoid(x) = 1 / (1 + exp(-x)). The RTL must not contain an exponential calculation.
The circuit is combinational.
Partitioning
x <= -4.0, output 5.x >= 4.0, output 250.Table
| x | -4.0 | -3.5 | -3.0 | -2.5 | -2.0 | -1.5 | -1.0 | -0.5 | 0.0 | 0.5 | 1.0 | 1.5 | 2.0 | 2.5 | 3.0 | 3.5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| y | 5 | 7 | 12 | 19 | 30 | 47 | 69 | 96 | 128 | 159 | 186 | 208 | 225 | 236 | 243 | 248 |
| Signal | Direction | Width | Description |
|---|---|---|---|
i_x | Input | 8 bits | Signed Q4.4 value |
o_y | Output | 8 bits | Unsigned sigmoid, scaled from 0 to 255 |