The following specifications apply for +4.25 V

fied. Boldface limits apply for T

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 8)

(Note 9)

(Limits)

FAN RPM-TO-DIGITAL CONVERTER

FAN1 and FAN2 Nominal Input

RPM (See

Section 6.0)

Divisor = 1, Fan Count = 153

(Note 12)

8800

RPM

Divisor = 2, Fan Count = 153

(Note 12)

4400

RPM

Divisor = 3, Fan Count = 153

(Note 12)

2200

RPM

Divisor = 4, Fan Count = 153

(Note 12)

1100

RPM

FAN3 Design Nominal Input RPM

Fan Count = 153 (Note 12)

4400

RPM

Internal Clock Frequency

+25˚C

≤ T

22.5

20.2

kHz (min)

24.8

kHz (max)

−10˚C

≤ T

22.5

19.1

kHz (min)

25.9

kHz (max)

DIGITAL OUTPUTS (VID4/NTEST, NMI/IRQ)

V

OUT(1)

Logical “1” Output Voltage

I

2.4

V (min)

V

OUT(0)

Logical “0” Output Voltage

I

0.4

V (max)

ISA D0–D7 DIGITAL OUTPUTS

V

OUT(1)

Logical “1” Output Voltage

I

2.4

V (min)

V

OUT(0)

Logical “0” Output Voltage

I

0.4

V (max)

I

OUT

V

0.005

1

µA (max)

V

−0.005

−1

µA (min)

OPEN DRAIN DIGITAL OUTPUTS (Power Switch Bypass, SDA, RESET, SMI, Chassis Intrusion)

V

OUT(0)

Logical “0” Output Voltage

I

0.4

V (min)

I

OH

High Level Output Current

V

0.1

100

µA (max)

RESET and Chassis Intrusion

45

20

ms (min)

Pulse Width

DIGITAL INPUTS: SMI__IN, VID0–VID3, VID4/NTEST, BTI, CS, A0, A1, A2, Mode Control and Interface Inputs (IORD, IOWR,

SYSCLK), Data Lines (D0–D7), Chassis Intrusion, and Tach Pulse Logic Inputs (FAN1, FAN2, FAN3)

V

IN(1)

Logical “1” Input Voltage

2.0

V (min)

V

IN(0)

Logical “0” Input Voltage

0.8

V (max)

SERIAL BUS DIGITAL INPUTS (SCL, SDA)

V

IN(1)

Logical “1” Input Voltage

0.7xV

CC

V (min)

V

IN(0)

Logical “0” Input Voltage

0.3xV

CC

V (max)

ALL DIGITAL INPUTS EXCEPT FOR BTI

I

IN(1)

Logical “1” Input Current

V

−0.005

−1

µA (min)

I

IN(0)

Logical “0” Input Current

V

0.005

1

µA (max)

C

IN

Digital Input Capacitance

20

pF

BIT DIGITAL INPUT

I

IN(1)

Logical “1” Input Current

V

1

10

µA (max)

I

IN(0)

Logical “0” Input Current

V

−500

−2000

µA (max)

C

IN

Digital Input Capacitance

20

pF

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