Electrical Characteristics

R

122 Intel® 82845 MCH for SDR Datasheet

6.4 DC Characteristics

Table 21. DC Characteristics

Symbol Signal
Group Parameter Min Typ Max Unit Notes
I/O Buffer Supply Voltage
VCCSM (u) P C133 SDRAM I/O Voltage 3.135 3.3 3.465 V
VCC1_8 (t) 1.8V I/O Supply Voltage 1.71 1.8 1.89 V
VCC1_5 (s) Core and AGP V oltage 1.425 1.5 1.575 V
VTT (r) Host AGT L+ Termination Voltage N/A N/A 1.75 V
Reference Voltages
HVREF (d) Host Address and Data Reference
Voltage
(2/3 x VTT) – 2% 2/3 x VTT (2/3 x VTT) + 2% V
HSWING (d) Host Compensation Reference
Voltage
(1/3 x VTT) – 2% 1/3 x VTT (1/3 x VTT) + 2% V
HI_REF (j) Hub Interface Reference Voltage 0.48 x VCC1_8 1/2 x VCC1_8 0.52 x VCC1_8 V
SDREF (n) SDRAM Reference Voltage 0.49 x VCCSM 1/2 x VCCSM 0.51 x VCCSM V
AGPREF (h) AGP Reference Voltage 0.48 x VCC1_5 1/2 x VCC1_5 0.52 x VCC1_5 V
System Bus Interface
VIL (a,c) Host AGTL+ Input Low Voltage (2/3 x VTT) – 0.1 V
VIH (a,c) H ost AGTL+ Input High Voltage (2/3 x VTT) + 0.1 V
VOL (a,b) Host AGTL+ Output Low Voltage (1/3 x VTT) + 0.1 V
VOH (a,b) Host AGT L+ Output High Voltage VTT-0.1 V
IOL (a,b) Host AGTL+ Output Low Current VTTmax / 0.75Rtt mA Rttmin = 45
Rtttyp = 50
Rttmax = 55
ILEAK (a,c) Host AGTL+ Input Leakage
Current
±15 µA VOL<Vpad<
VTT
CPAD (a,c) Host AGTL+ Input Capacitance 1.0 pF
3.3 V Interface
VIL (k,m,p) Input Low Voltage SDREF – 2.0 V
VIH (k,m,p) Input High Voltage SDREF + 2.0 V
VOL (k,l) Output Low Voltage 0.4 V
VOH (k,l) Output High Voltage 2.4 V
IOL (k,l) Output Low Current 4 mA @VOL_S max
IOH (k,l) Output High Current -4 mA @VOH_S max
ILEAK (k,m,p) Input Leakage Current ±100 µA 0<Vin<VCC3_3