Datasheet

Datasheet 27
Electrical Specifications
Table 14. 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_PU
GTLREF pull up resistor on
975X and 96x Express
Chipset family boards
124 * 0.99 124 124 * 1.01 Ω
2
2. GTLREF is to be generated from V
TT
by a voltage divider of 1% resistors (one divider for each
GTLEREF land).
GTLREF_PD
GTLREF pull down resistor
on 975X and 96x Express
Chipset family boards
210 * 0.99 210 210 * 1.01 Ω
2
GTLREF_PU
GTLREF pull up resistor on
Intel Series 3 Express
Chipset family boards
100 * 0.99 100 100 * 1.01 Ω
2
GTLREF_PD
GTLREF pull down resistor
on Intel Series 3 Express
Chipset chipset family
boards
200 * 0.99 200 200 * 1.01 Ω
2
R
TT
Termination Resistance 45 50 55 Ω
3
3. R
TT
is the on-die termination resistance measured at V
TT
/3 of the GTL+ output driver.
COMP[3:0] COMP Resistance 49.40 49.90 50.40 Ω
4
4. COMP resistance must be provided on the system board with 1% resistors. COMP[3:0] and
COMP8 resistors are to V
SS
.
COMP8 COMP Resistance 24.65 24.90 25.15 Ω
4