Intel Celeron 440 HH80557RG041512 Datenbogen
Produktcode
HH80557RG041512
Datasheet
27
Electrical Specifications
2.7.3.1
GTL+ Front Side Bus Specifications
In most cases, termination resistors are not required as these are integrated into the
processor silicon. See
for details on which GTL+ signals do not include on-die
termination.
Valid high and low levels are determined by the input buffers by comparing with a
reference voltage called GTLREF.
lists the GTLREF specifications for both
50 Ohm and 60 Ohm platforms. The GTL+ reference voltage (GTLREF) should be
generated on the system board using high precision voltage divider circuits.
NOTES:
1.
1.
Unless otherwise noted, all specifications in this table apply to all processor frequencies.
2.
GTLREF is to be generated from V
TT
by a voltage divider of 1% resistors (one divider for
each GTLEREF land).
3.
R
TT
is the on-die termination resistance measured at V
TT
/3 of the GTL+ output driver.
4.
COMP resistance must be provided on the system board with 1% resistors. COMP[3:0] and
COMP8 resistors are to V
COMP8 resistors are to V
SS
.
Table 14.
GTL+ Bus Voltage Definitions
Symbol
Parameter
Min
Typ
Max
Units Notes
1
GTLREF_PU
GTLREF pull up resistor
124 * 0.99
124
124 * 1.01
Ω
GTLREF_PD
GTLREF pull down resistor
210 * 0.99
210
210 * 1.01
Ω
2, 4
R
TT
Termination Resistance
45
50
55
Ω
3
COMP[3:0]
60 Ω Platform termination
Resistance
Resistance
60.4 * 0.99
60.4
60.4 * 1.01
Ω
4
50 Ω Platform termination
Resistance
Resistance
49.9 * 0.99
49.9
49.9 * 1.01
Ω
4
COMP8
60 Ω Platform termination
Resistance
Resistance
30.1 * 0.99
30.1
30.1 * 1.01
Ω
4
50 Ω Platform termination
Resistance
Resistance
24.9 * 0.99
24.9
24.9 * 1.01
Ω
4