EP3C16E144C8N Datasheet, PDF (8/34 Pages) Altera Corporation – 1. Cyclone III Device Datasheet

1–8
Chapter 1: Cyclone III Device Datasheet
Electrical Characteristics
Example 1–1 shows you the example to calculate the change of 50 I/O impedance
from 25°C at 3.0 V to 85°C at 3.15 V:
Example 1–1.
R_V = (3.15 – 3) × 1000 × –0.026 = –3.83
R_T = (85 – 25) × 0.262 = 15.72
Because R_V is negative,
MF_V = 1 / (3.83/100 + 1) = 0.963
Because R_T is positive,
MF_T = 15.72/100 + 1 = 1.157
MF = 0.963 × 1.157 = 1.114
R_final = 50 × 1.114 = 55.71 
Pin Capacitance
Table 1–9 lists the pin capacitance for Cyclone III devices.
Table 1–9. Cyclone III Devices Pin Capacitance
Symbol
Parameter
Typical – Typical –
QFP
FBGA
Unit
C_IOTB
Input capacitance on top/bottom I/O pins
7
C_IOLR
Input capacitance on left/right I/O pins
7
C_LVDSLR
Input capacitance on left/right I/O pins with dedicated
LVDS output
8
6
pF
5
pF
7
pF
C_VREFLR
(1)
C_VREFTB
(1)
C_CLKTB
Input capacitance on left/right dual-purpose VREF pin
when used as V_REF or user I/O pin
Input capacitance on top/bottom dual-purpose VREF pin
when used as V_REF or user I/O pin
Input capacitance on top/bottom dedicated clock input
pins
21
23 ⁽²⁾
7
21
pF
23 ⁽²⁾
pF
6
pF
C_CLKLR Input capacitance on left/right dedicated clock input pins
6
5
pF
Notes to Table 1–9:
(1) When VREF pin is used as regular input or output, a reduced performance of toggle rate and t_CO is expected due to
higher pin capacitance.
(2) C_VREFTB for EP3C25 is 30 pF.
Cyclone III Device Handbook
Volume 2
July 2012 Altera Corporation