Array-divider cell circuit: build and simulate it online
One cell of a restoring array divider: subtract, then keep the old bit if the subtraction borrowed.
Build the array-divider cell in the free online simulator — it checks your circuit automatically.
What you need
- 3 logic switches labelled S, M, Bin
- 2 probes labelled R, Bout
- 2 XOR gates
- a 2:1 multiplexer
Step by step
- Inputs and outputs. From the Logic section of the library, drop digital inputs (0/1 boxes) or logic switches for the inputs, and digital outputs or probes for the outputs; give each its label in the inspector (the checker finds them by label). Switches S (remainder bit), M (divisor bit), Bin; Probes R (result bit), Bout
- A full subtractor. D = S ⊕ M ⊕ Bin, Bout = S̄M + S̄Bin + M·Bin. 2 XOR, NOT, AND, OR
- The restore multiplexer. If the cell borrowed, the subtraction did not fit: pass S through instead of D. A 2:1 mux with Bout on its select. Multiplexer (1 select line): D0 = D, D1 = S, S0 = Bout
- Prove it. All 8 rows.
Truth table
| S | M | Bin | R | Bout |
|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 |
| 0 | 0 | 1 | 0 | 1 |
| 0 | 1 | 0 | 0 | 1 |
| 0 | 1 | 1 | 0 | 1 |
| 1 | 0 | 0 | 1 | 0 |
| 1 | 0 | 1 | 0 | 0 |
| 1 | 1 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 | 1 |
Frequently asked questions
How do you build a array-divider cell?
One cell of a restoring array divider: subtract, then keep the old bit if the subtraction borrowed. In short: inputs and outputs, then a full subtractor, then the restore multiplexer, then prove it.
What is the truth table of a array-divider cell?
It has 3 inputs (S, M, Bin) and 2 outputs (R, Bout), so 8 rows. The full table is on this page; the Embedded Lab checks all of them against your circuit.
What parts do you need for a array-divider cell?
2 XOR gates; a 2:1 multiplexer — plus logic switches for the inputs and probes for the outputs.
Can I simulate a array-divider cell online for free?
Yes. Open it in the BitForBytes Embedded Lab, a free browser-based circuit and logic simulator: drag in the gates, wire them, and press "Check my circuit" — every input combination is simulated and marked for you. No download or sign-up needed.
Part of DSD 27 · Dividers in the free BitForBytes digital system design course.