Intel Celeron D Processor 300 Sequence

Datasheet 31
Electrical Specifications
2.13 GTL+ FSB Specifications
Termination resistors are not required for most GTL+ signals, as these are integrated into the
processor silicon.
Valid high and low levels are determined by the input buffers which compare a signal’s voltage
with a reference voltage called GTLREF.
Table 2-17 lists the GTLREF specifications. The GTL+ reference voltage (GTLREF) should be
generated on the system board using high precision voltage divider circuits.
§
Table 2-17. GTL+ Bus Voltage Definitions
Symbol Parameter Min Typ Max Units Notes
1
NOTES:
1. Unless otherwise noted, all specifications in this table apply to all processor frequencies.
GTLREF
Bus Reference
Voltage
(0.98 * 0.67) * V
TT
0.67 * V
TT
(1.02 * 0.67) * V
TT
V
2, 3, 4
2. The tolerances for this specification have been stated generically to enable the system designer to calculate the minimum
and maximum values across the range of V
TT
.
3. GTLREF should be generated from V
TT
by a voltage divider of 1% resistors or 1% matched resistors.
4. The V
TT
referred to in these specifications is the instantaneous V
TT
.
R
PULLUP
On die pullup for
BOOTSELECT
signal
500 — 5000 Ω
5
5. These pull-ups are to V
TT
.
R
TT
Termination
Resistance
54 60 66 Ω
6
6. R
TT
is the on-die termination resistance measured at V
TT
/2 of the GTL+ output driver.
COMP[1:0] COMP Resistance 59.8 60.4 61 Ω
7
7. COMP resistance must be provided on the system board with 1% resistors. COMP[1:0] resistors are to V
SS
. COMP[3:2]
resistors are to V
TT
. COMP[5:4] resistors are to V
TT
.
COMP[3:2] COMP Resistance 99 100 101 Ω
7
COMP[5:4] COMP Resistance 59.8 60.4 61 Ω
7