AC INPUT CHARACTERISTICS
Parameter
Symbol
Min
Max
Notes
AC Input Logic High (See Figure 4)
VIH (ac)
Vref + 200 mV
AC Input Logic Low (See Figures 2 and 4)
VIL (ac)
Vref – 200 mV
1
Input Reference Peak to Peak ac Voltage
Vref (ac)
5% Vref (dc)
2
Clock Input Differential Voltage
Vdif (ac)
400 mV
VDDQ + 600 mV
3
NOTES:
1. Inputs may undershoot to – 0.5 V (peak) for up to 20% tKHKH (e.g., 2 ns at a clock cycle time of 10 ns).
2. Although considerable latitude in the selection of the nominal dc value (i.e., rms value) of Vref is supported, the peak to peak ac component
superimposed on Vref may not exceed 5% of the dc component of Vref.
3. Minimum instantaneous differential input voltage required for differential input clock operation.
VOH
VSS
50%
100%
20% tKHKH
Figure 2. Undershoot Voltage
VDDQ
VTR
VDIF
CROSSING POINT
VCP
VCM*
VSS
*VCM, the Common Mode Input Voltage, equals VTR – ((VTR – VCP)/2).
Figure 3. Differential Inputs/Common Mode Input Voltage
VIH(ac)
Vref
VIL(ac)
Figure 4. Differential Inputs/Common Mode Input Voltage
MOTOROLA FAST SRAM
MCM69L736A•MCM69L818A
9