TrueSound DCC by ZIMO can control pulsed smoke units allowing for chuff synchronized smoke generation for steam engines and load dependent smoke generation for Diesel engines.

See for yourself:
1. Steam Engine:

2. Diesel Engine

More examples on our Youtube channel

Dimensions:
Length: 2" (2 1/2" is the overall length with mounting holders)
Width: 1 1/8" (1 1/2" with mounting bars - can be cut off if not used)
Height: 1 1/8" (including the smoke funnel on top)