On-Chip Power Minimization Using Serialization-Widening with Frequent Value Encoding

Table 1

Serialization may increase or decrease switching activity. Parts (a) and (b) illustrate two different 16-bit data streams passing through a conventional 8-bit bus and a serialized 4-bit bus. In example (a) switching activity decreases, while in (b) it increases.

(a) 16-bit data stream→0011 0011 0011 0011

Passing through 8-bit bus →	Data sequence	Signal	Coupling
	0000 0000	—	—
	0011 0011	4	3
	0011 0011	0	0
	Total number of transitions	4	3
Passing through 4-bit bus →	Data sequence	Signal	Coupling
	0000	—	—
	0011	2	1
	0011	0	0
	0011	0	0
	0011	0	0
	Total number of transitions	2	1

(b) 16-bit data stream→0011 1100 0011 1100

Passing through - bit bus →	Data sequence	Signal	Coupling
	0000 0000	—	—
	0011 1100	4	2
	0011 1100	0	0
	Total number of transitions	4	2
Passing through 4 bit-bus →	Data sequence	Signal	Coupling
	0000	—	—
	0011	2	1
	1100	2	2
	0011	2	2
	1100	2	2
	Total number of transitions	8	7