User guide

AC Electrical Characteristics
The following specifications apply for V
DD
= 3.0 VDC to 3.6 VDC, and all analog source impedance R
S
=50Ω unless other-
wise specified in the conditions. Boldface limits apply for T
A
=T
MIN
to T
MAX
; all other limits T
A
= +25˚C.
Symbol Parameter Conditions
Typical
(Note 7)
Limits
(Note 8)
Units
(Limit)
TACHOMETER ACCURACY
Fan Control Accuracy
±
10 % (max)
Fan Full-Scale Count 65535 (max)
Fan Counter Clock Frequency 90 kHz
Fan Count Update Frequency 1.0 Hz
FAN PWM OUTPUT
Frequency Accuracy
±
10 % (max)
Digital Electrical Characteristics
Symbol Parameter Conditions
Typical
(Note 7)
Limits
(Note 8)
Units
(Limit)
V
IH
Logical High Input Voltage 2.1 V (min)
V
IL
Logical Low Input Voltage 0.8 V (max)
I
IH
Logical High Input Current V
IN
=V
DD
0.005 +10 µA (max)
I
IL
Logical Low Input Current V
IN
= GND −0.005 −10 µA (max)
C
IN
Digital Input Capacitance 20 pF
SMBus Logical Electrical Characteristics
The following specifications apply for V
DD
= 3.0 VDC to 3.6 VDC, and all analog source impedance R
S
=50Ω unless other-
wise specified in the conditions. Boldface limits apply for T
A
=T
MIN
to T
MAX
; all other limits T
A
= +25˚C.
Symbol Parameter Conditions
Typical
(Note 7)
Limits
(Note 8)
Units
(Limit)
SMBDAT OPEN-DRAIN OUTPUT
V
OL
Logic Low Level Output Voltage I
OL
=4mA 0.4 V (max)
I
OH
High Level Output Current V
OUT
=V
DD
0.03 10 µA (max)
SMBDAT, SMBCLK INPUTS
V
IH
Logical High Input Voltage 2.1 V (min)
V
IL
Logical Low Input Voltage 0.8 V (max)
V
HYST
Logic Input Hysteresis Voltage 320 mV
LM63
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