Archive Entry

Choose-n Arbiter

OTHERCOMBother-combinationalOTHERCOMB007Archived Feb 15, 2026

✅Tested & Functional

Authors:RCS_33

Endorsed by:mattbatwings

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Chooses n true bitDefinition: Guide to data storage sizes: **Bit**: The smallest unit of data, representing a 0 or a 1 in binary. Abbreviated as b **Nibble**: One hexadecimal 'digit,' representing either **4 bits** or the 16 ...s out of a k-wide bit vector based on left/right sided priority. if there are at least n set bits in the vector, the arbiter guarantees to choose n of them

Input:

1. bit vector to choose from
2. bit vector to disable a choosing layer

Output: n bit vectors of length k with at most 1 set bit

Speed: (ceil of the fraction)

1. 1t per k/5 (wire delay)
2. 2t per n (no base delay)

Size:

1. 3-wide tileable per k
2. 4-wide tileable per n
3. 5 high

Use cases: -> comes in handy when wanting to choose multiple entries in a set recursively to convert some of the bandwidth to througput -> if you want to design OoO Cores, you will properbly need this a lot

Notes:

1. since stackDefinition: LIFO: A data structure where the last input is outputted first (LIFO, Last in first out). For example, when the numbers 1, 2, 3, 4 are inputted in that order, they are outputted in the reverse ord...ing might be confusing, I marked the region to stack with gold blocks
2. the design is optimal in both speed and size. This is the 5th Iteration, trust me. (There is also a Vertical Version with equal Timings)

Schematic Content: n = 4 k = 10 (2 modules. Each module consists of 4 normal layers and 1 repeater layer)