Intel Celeron 440 HH80557RG041512 Data Sheet

Datasheet

27

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.

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

SS

. 

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

60.4 * 0.99

60.4

60.4 * 1.01

Ω

4

50 Ω Platform termination 
Resistance

49.9 * 0.99

49.9

49.9 * 1.01

Ω

4

COMP8

60 Ω Platform termination 
Resistance

30.1 * 0.99

30.1

30.1 * 1.01

Ω

4

50 Ω Platform termination 
Resistance

24.9 * 0.99

24.9

24.9 * 1.01

Ω

4