The following specifications apply for +2.8 V

+

≤ +3.8 V

+

≤ +5.75 V

IN0-IN6 R

25˚C.(Note 7)

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 8)

(Note 9)

(Limits)

FAN RPM-to-DIGITAL CONVERTER

Fan RPM Error

+25˚C

≤ T

% (max)

−10˚C

≤ T

% (max)

−25˚C

≤ T

% (max)

Full-scale Count

255

(max)

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

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)

−25˚C

≤ T

22.5

18

kHz (min)

27

kHz (max)

DIGITAL OUTPUTS: A0/NTEST_OUT, INT

V

OUT(1)

Logical “1” Output Voltage

I

V

at V

2.4

V (min)

V

OUT(0)

Logical “0” Output Voltage

I

V

at V

0.4

V (max)

OPEN DRAIN OUTPUTS: GPO, RST_OUT/OS, CI

V

OUT(0)

Logical “0” Output Voltage

I

at V

I

0.4

V (min)

I

OH

High Level Output Current

V

+

0.1

100

µA (max)

RST_OUT/OS, CI

30

10

ms (min)

Pulse Width

OPEN DRAIN SERIAL BUS OUTPUT: SDA

V

OUT(0)

Logical “0” Output Voltage

I

V

+

= +5.75V, I

at V

0.4

V (min)

I

OH

High Level Output Current

V

+

0.1

100

µA (max)

DIGITAL INPUTS: A0/NTEST_Out, A1-A2, BTI, CI (Chassis Intrusion), INT_IN, and NTEST_IN/Reset_IN

V

IN(1)

Logical “1” Input Voltage

2.0

V (min)

V

IN(0)

Logical “0” Input Voltage

0.8

V (max)

SERIAL BUS INPUTS (SCL, SDA) and FAN TACH PULSE INPUTS (FAN1, FAN2)

V

IN(1)

Logical “1” Input Voltage

0.7xV

+

V (min)

V

IN(0)

Logical “0” Input Voltage

0.3xV

+

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

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