Altera Cyclone IV, Руководство по эксплуатации устройства

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Chapter 1: Cyclone IV Device Datasheet 1–7
Operating Conditions
December 2016 Altera Corporation Cyclone IV Device Handbook,
Volume 3
DC Characteristics
This section lists the I/O leakage current, pin capacitance, on-chip termination (OCT)
tolerance, and bus hold specifications for Cyclone IV devices.
Supply Current
The device supply current requirement is the minimum current drawn from the
power supply pins that can be used as a reference for power size planning. Use the
Excel-based early power estimator (EPE) to get the supply current estimates for your
design because these currents vary greatly with the resources used.
Table 1–6 lists the
I/O pin leakage current for Cyclone IV devices.
Bus Hold
The bus hold retains the last valid logic state after the source driving it either enters
the high impedance state or is removed. Each I/O pin has an option to enable bus
hold in user mode. Bus hold is always disabled in configuration mode.
Table 1–7 lists bus hold specifications for Cyclone IV devices.
Table 1–6. I/O Pin Leakage Current for Cyclone IV Devices
(1) , (2)
Symbol Parameter Conditions Device Min Typ Max Unit
I
I
Input pin leakage current V
I
= 0 V to V
CCIOMAX
— –10 — 10

A
I
OZ
Tristated I/O pin leakage
current
V
O
= 0 V to V
CCIOMAX
— –10 — 10

A
Notes to Table 1–6 :
(1) This value is specified for normal device operation. The value varies during device power
-
up. This applies for all V
CCIO
settings (3.3, 3.0, 2.5,
1.8, 1.5, and 1.2 V).
(2) The 10

A I/O leakage current limit is applicable when the internal clamping diode is off. A higher current can be observed when the diode is on.
Table 1–7. Bus Hold Parameter for Cyclone IV Devices (Part 1 of 2)
(1)
Parameter Condition
V
CCIO
(V)
Unit 1.2 1.5 1.8 2.5 3.0 3.3
Min Max Min Max Min Max Min Max Min Max Min Max
Bus hold
low,
sustaining
current
V
IN
> V
IL
(maximum)
8 — 12 — 30 — 50 — 70 — 70 —

A
Bus hold
high,
sustaining
current
V
IN
< V
IL
(minimum)
–8 — –12 — –30 — –50 — –70 — –70 —

A
Bus hold
low,
overdrive
current
0 V < V
IN
< V
CCIO
— 125 — 175 — 200 — 300 — 500 — 500

A
Bus hold
high,
overdrive
current
0 V < V
IN
< V
CCIO
— –125 — –175 — –200 — –300 — –500 — –500

A