Dc electrical characteristics, Lm87 – Rainbow Electronics LM87 User Manual
Page 5
DC Electrical Characteristics
(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)
Symbol
Parameter
Conditions
Typical
Limits
Units
(Limits)
DAC CHARACTERISTICS
DAC Error
0 ˚C
≤ T
A
≤ +75 ˚C, V
+
=
3.3 V, Code = 255
-3.3
% (min)
V
+
= 3.3 V, 3/4 Scale,
code 192
+3.7
%
0 ˚C
≤ T
A
≤ +75 ˚C, V, V
+
= 3.3 V, Code = 8(Note
±
3
% (max)
R
L
Output Load Resistance
V
O
= 2.5 V
1250
Ω (min)
C
L
Output Load Capacitance
20
pF (max)
FAN RPM-TO-DIGITAL CONVERTER
Fan RPM Error
+25 ˚C
≤ T
A
≤ +75 ˚C
±
10
% (max)
−10 ˚C
≤ T
A
≤ +100 ˚C
±
15
% (max)
−40 ˚C
≤ T
A
≤ +125 ˚C
±
20
% (max)
Full-scale Count
255
(max)
FAN1 and FAN2 Nominal Input
RPM (See Section 6.0)
Divisor = 1, Fan Count =
153 (Note 16)
8800
RPM
Divisor = 2, Fan Count =
153 (Note 16)
4400
RPM
Divisor = 3, Fan Count =
153 (Note 16)
2200
RPM
Divisor = 4, Fan Count =
153 (Note 16)
1100
RPM
DIGITAL OUTPUTS (NTEST_OUT)
V
OUT(1)
Logical “1” Output Voltage
I
OUT
=
±
3.0 mA at
V
+
= +2.8 V
2.4
V (min)
V
OUT(0)
Logical “0” Output Voltage
I
OUT
=
±
3.0 mA at
V
+
= +3.8 V
0.4
V (max)
OPEN- DRAIN DIGITAL OUTPUTS (SMBData, RESET#, CI, INT#, THERM#)
V
OUT(0)
Logical “0” Output Voltage (SMBData)
I
OUT
= −755 µA
0.4
V (min)
V
OUT(0)
Logical “0” Output Voltage (Others)
I
OUT
= −3 mA
0.4
V (min)
I
OH
High Level Output Current
V
OUT
= V
+
5
12
µA (max)
RESET# and Chassis Intrusion
45
20
ms (min)
Pulse Width
DIGITAL INPUTS: VID0–VID4, NTEST_IN, ADD/NTEST_OUT, Chassis Intrusion (CI)
V
IN(1)
Logical “1” Input Voltage
2.0
V (min)
V
IN(0)
Logical “0” Input Voltage
0.8
V (max)
SMBus DIGITAL INPUTS (SMBCLK, SMBData)
V
IN(1)
Logical “1” Input Voltage
2.1
V (min)
V
IN(0)
Logical “0” Input Voltage
0.8
V (max)
V
HYST
Input Hysteresis Voltage
243
mV
Tach Pulse Logic Inputs (FAN1, FAN2)
V
IN(1)
Logical “1” Input Voltage
0.7 x V
+
V (min)
V
IN(0)
Logical “0” Input Voltage
0.3 x V
+
V (max)
ALL DIGITAL INPUTS
I
IN(1)
Logical “1” Input Current
V
IN
= V
+
−12
µA (min)
I
IN(0)
Logical “0” Input Current
V
IN
= 0 V
DC
12
µA (max)
C
IN
Digital Input Capacitance
20
pF
LM87
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