LM87
DC Electrical Characteristics
Symbol
DAC CHARACTERISTICS
DAC Error
Parameter
(Continued)
The following specifications apply for +2.8 V
DC
≤
V
+
≤
+3.8 V
DC
, Analog voltage inputs R
S
= 510
Ω,
unless otherwise speci-
fied.
Boldface limits apply for T
A
= T
J
= T
MIN
to T
MAX
;
all other limits T
A
= T
J
= 25 ˚C.(Note 8)
Conditions
Typical
0 ˚C
≤
T
A
≤
+75 ˚C, V
+
=
3.3 V, Code = 255
V
+
= 3.3 V, 3/4 Scale,
code 192
0 ˚C
≤
T
A
≤
+75 ˚C, V, V
+
= 3.3 V, Code = 8(Note
R
L
C
L
Output Load Resistance
Output Load Capacitance
Fan RPM Error
+25 ˚C
≤
T
A
≤
+75 ˚C
−10 ˚C
≤
T
A
≤
+100 ˚C
−40 ˚C
≤
T
A
≤
+125 ˚C
Full-scale Count
FAN1 and FAN2 Nominal Input
RPM (See
Section 6.0)
Divisor = 1, Fan Count =
153 (Note 16)
Divisor = 2, Fan Count =
153 (Note 16)
Divisor = 3, Fan Count =
153 (Note 16)
Divisor = 4, Fan Count =
153 (Note 16)
8800
4400
2200
1100
V
O
= 2.5 V
+3.7
Limits
-3.3
Units
(Limits)
% (min)
%
±
3
% (max)
1250
20
Ω
(min)
pF (max)
% (max)
% (max)
% (max)
(max)
RPM
RPM
RPM
RPM
FAN RPM-TO-DIGITAL CONVERTER
±
10
±
15
±
20
255
DIGITAL OUTPUTS (NTEST_OUT)
V
OUT(1)
V
OUT(0)
Logical “1” Output Voltage
Logical “0” Output Voltage
I
OUT
=
±
3.0 mA at
V
+
= +2.8 V
I
OUT
=
±
3.0 mA at
V
+
= +3.8 V
I
OUT
= −755 µA
I
OUT
= −3 mA
V
OUT
= V
+
5
45
2.4
0.4
V (min)
V (max)
OPEN- DRAIN DIGITAL OUTPUTS (SMBData, RESET#, CI, INT#, THERM#)
V
OUT(0)
V
OUT(0)
I
OH
Logical “0” Output Voltage (SMBData)
Logical “0” Output Voltage (Others)
High Level Output Current
RESET# and Chassis Intrusion
Pulse Width
DIGITAL INPUTS: VID0–VID4, NTEST_IN, ADD/NTEST_OUT, Chassis Intrusion (CI)
V
IN(1)
V
IN(0)
V
IN(1)
V
IN(0)
V
HYST
V
IN(1)
V
IN(0)
I
IN(1)
I
IN(0)
C
IN
Logical “1” Input Voltage
Logical “0” Input Voltage
Logical “1” Input Voltage
Logical “0” Input Voltage
Input Hysteresis Voltage
Logical “1” Input Voltage
Logical “0” Input Voltage
Logical “1” Input Current
Logical “0” Input Current
Digital Input Capacitance
5
0.4
0.4
12
20
V (min)
V (min)
µA (max)
ms (min)
2.0
0.8
2.1
0.8
243
0.7 x V
+
0.3 x V
V
IN
= V
+
V
IN
= 0 V
DC
20
−12
12
+
V (min)
V (max)
V (min)
V (max)
mV
V (min)
V (max)
µA (min)
µA (max)
pF
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SMBus DIGITAL INPUTS (SMBCLK, SMBData)
Tach Pulse Logic Inputs (FAN1, FAN2)
ALL DIGITAL INPUTS
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