Datasheet
Datasheet 47
Signal Quality Specifications
NOTES:
1. Unless otherwise noted, all specifications in this table apply to all Pentium III processor frequencies and
cache sizes.
2. Non-AGTL+ signals except PWRGOOD.
There are three signal quality parameters defined for both AGTL+ and non-AGTL+ signals:
overshoot/undershoot, ringback, and settling limit. All three signal quality parameters are shown in
Table 24 for the AGTL+ and non-AGTL+ signal group.
NOTES:
1. Unless otherwise noted, all specifications in this table apply to all Pentium III processor frequencies and
cache sizes.
2. These values are specified at the processor core pins.
3. Specifications are for the edge rate of 0.3 – 0.8
V
/
ns
. See Figure 16 for the generic waveform.
4. See Table 22 for maximum allowable overshoot.
5. Ringback between V
REF
+ 100 mV and V
REF
+ 200 mV or V
REF
–200 mV and V
REF
– 100 mV requires the
flight time measurements to be adjusted as described in the AGTL+ Specification (Intel
®
Pentium
®
II
Developers Manual). Ringback below V
REF
+ 100 mV or above V
REF
– 100 mV is not supported.
6. Intel recommends simulations not exceed a ringback value of V
REF
± 200 mV to allow margin for other
sources of system noise.
7. A negative value for ρ
ρ indicates that the amplitude of ringback is above V
REF
. (i.e., f = -100 mV specifies the
signal cannot ringback below V
REF
+ 100 mV).
8. φ
φ and ρρ: are measured relative to V
REF
. αα: is measured relative to V
REF
+ 200 mV.
Table 23. Signal Ringback Specifications for Signal Simulation
Input Signal Group Transition
Maximum Ringback
(with Input Diodes Present)
Unit Figure Notes
1
AGTL+ 0 → 1V
REF
+ 0.200 V 16
AGTL+ 1 → 0V
REF
– 0.200 V 16
Non-AGTL+ Signals 0 → 11.7V16 2
Non-AGTL+ Signals 1 → 00.7V16 2
PWRGOOD 0 → 1 2.00 V 16
Table 24. AGTL+ and Non-AGTL+ Signal Groups Ringback Tolerance Specifications
1, 2, 3, 4
T# Parameter Min Unit Figure Notes
α
α: Overshoot 100 mV 16 4, 8
τ
τ: Minimum Time at High 0.50 ns 16
ρ
ρ: Amplitude of Ringback –200 mV 16 5, 6, 7, 8
φ
φ: Final Settling Voltage 200 mV 16 8
δ
δ: Duration of Squarewave Ringback N/A ns 16