Data Sheet
Preliminary
PowerPC 970FX
Figure 3-6. Post-IAP Eye Opening
V
/2
BIT
V
EYE
V
REF-SSB
V
EYE
V
/2
BIT
T
EYE
T
BIT
The reference level for VEYE is VREF-SSB. Horizontal (TEYE) eye opening is a function of the bit time (TBIT) and the
earliness of the bus clock transition relative to the slowest data signal.
Table 3-15. Eye-Size Requirements
Eye
Requirement
(ps)
Bit Rate
(Mb/s)
CPU Bus
Ratio
CPU Core
(MHz)
Step Time
(ps)
V
EYE
(Minimum)
Bit Time (ps)
Eye/Bit Time
400
450
500
500
666
666
866
1066
3
3
3
2
3
2
2
2
1200
1350
1500
1000
1998
1332
1732
2132
31.9
31.9
31.9
31.9
27.8
31.9
31.9
26.0
863
797
744
744
605
625
544
465
2500
2222.2
2000
34.5%
34.5%
37.2%
37.2%
40.3%
41.6%
47.1%
49.6%
150mv
150mv
150mv
150mv
150mv
150mv
150mv
150mv
2000
1501.5
1501.5
1154.7
938.1
Electrical and Thermal Characteristics
Page 29 of 74
October 14, 2005
IBM [ IBM ]
