EP2C20F256C8N Datasheet, PDF (112/470 Pages) Altera Corporation – Cyclone II Device Handbook, Volume 1

Operating Conditions
Figure 5–1. Receiver Input Waveforms for Differential I/O Standards
Single-Ended Waveform
V_ICM (2)
V_ID (1)
Positive Channel (p) = V_IH
Negative Channel (n) = V_IL
Ground
Differential Waveform (Mathematical Function of Positive and Negative Channel)
V_ID (1)
0V
V_ID (1)
p − n (3)
Notes to Figure 5–1:
(1) V_ID is the differential input voltage. V_ID = |p – n|.
(2) V_ICM is the input common mode voltage. V_ICM = (p + n)/2.
(3) The p – n waveform is a function of the positive channel (p) and the negative channel (n).
5–8
Cyclone II Device Handbook, Volume 1
Altera Corporation
February 2008