3 ac specifications, Datasheet, Table 21. ac specifications for pci signaling – Intel GD82559ER User Manual

Page 82

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GD82559ER — Networking Silicon

76

Datasheet

10.3

AC Specifications

NOTES:

1. Switching Current High specifications are not relevant to PME#, SERR#, or INTA#, which are open drain

outputs.

2. Maximum current requirements will be met as drivers pull beyond the first step voltage (AC drive point).

Equations defining these maximums (A and B) are provided. To facilitate component testing, a maximum
current test point is defined for each side of the output driver.

Figure 25. RBIAS10 Resistance Versus Transmitter Current

Rbias10

621.5 0hm

549 Ohm

576 Ohm

Icct10

19mA

20 mA

21mA

Table 21. AC Specifications for PCI Signaling

Symbol

Parameter

Condition

Min

Max

Units

Notes

I

OH(AC)

Switching

Current High

0 < V

out

1.4

-44

mA

1

1.4 < V

out

< 0.9V

CC

-17.1(V

CC

- V

out

)

mA

1

0.7V

CC

< V

out

< V

CC

Eqn A

mA

2

(Test Point)

V

out

= 0.7V

CC

-32V

CC

mA

2

I

OL(AC)

Switching

Current Low

V

out

2.2

95

mA

1

2.2 > V

out

> 0.1V

CC

V

out

/0.023

mA

1

0.18V

CC

> V

out

> 0

Eqn B

mA

2

(Test Point)

V

out

= 0.18V

CC

38V

CC

mA

2

I

CL

Low Clamp
Current

-3 < V

in

-1

-25 + (V

in

+ 1)/

0.015

mA

3

I

CH

High Clamp
Current

V

CC

+4 > V

in

V

CC

+1

25 + (V

in

-V

CC

-1)/

0.015

mA

3

slew

RP

PCI Output Rise
Slew Rate

0.4 V to 2.4 V

1

4

V/ns

slew

FP

PCI Output Fall
Slew Rate

2.4 V to 0.4 V

1

4

V/ns

Equation A.

I

OH

= (98/V

CC

)

*

(V

out

- V

CC

)

*

(V

out

+ 0.4V

CC

), for V

CC

> V

out

> 0.7V

CC

Equation B.

I

OL

= (256/V

CC

)

*

(V

out

)

*

(V

CC

- V

out

), for 0 < V

out

< 0.18V

CC

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