Puzzle 8 of 100

Short crossings

Goal

Connect A to Y, B to Z, and C to W. Every output must follow its input within about a third of a nanosecond of the target.

Die: 15 by 11 squares
Layers: Metal, Polysilicon, Contact
Inputs: A, B, C
Outputs: Y, Z, W

Go to the solution

New in this puzzle

Short bridges

Polysilicon slows a signal, and a longer stretch slows it more. Cross under metal with as few squares of polysilicon as you can, and carry the rest of the path in metal.

Hint

The paths of B and C cross each other and the path of A, so each crossing needs polysilicon under metal. Keep each stretch of polysilicon short and carry the rest of the path in metal. One bridge can pass under two lines.

Solution

This is the game's reference drawing for the puzzle. It meets the goal and passes the design rules. Other drawings can pass as well.

Top View of the solved die for puzzle 8, Short crossings, with the Side View below it. — Top View of the solved die, captured from the game. Paths that carry a high level at the moment shown are lit. The Side View below cuts through the row between the dashed lines.

The game window in Isometric View with the solved die for puzzle 8, Short crossings, the guide, and the scope. — The whole game window in Isometric View. The scope on the right compares each output with its target band, and the message above it confirms that the drawing passes.

Solution drawing for puzzle 8, Short crossings, drawn on a numbered grid with every layer in its game color and pattern. — The solution on the grid. Squares are numbered from the top left corner, so you can count them.

Legend

Metal49 squares
Polysilicon12 squares
Contact4 squares
Input padA, B, C
Output padY, Z, W

About the drawing

The drawing uses 54 of the die's 165 squares.
The die starts empty, so you draw every square.
4 contacts join metal to the polysilicon or active silicon under it.