LM96194CISQ/NOPB National Semiconductor, LM96194CISQ/NOPB Datasheet - Page 15

• Manufacturer Part Number: LM96194CISQ/NOPB
• Description: IC TRUTHERM HDWR MONITOR 48-LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®, TruTherm®r

Specifications of LM96194CISQ/NOPB

• Function: Fan Control, Temp Monitor
• Topology: ADC (Sigma Delta), Comparator, Fan Control, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 85°C, External Sensor
• Output Type: SMBus™
• Output Alarm: No
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-LLP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM96194CISQTR

Transient VID values caused by line-to-line skew are ignored
by the LM96194. See the VRM/VRD specifications for the
worst case line-to-line skew.
The LM96194 averages the VID values over a sampling win-
dow to determine the average voltage that the VID input was
indicating during the sampling window. At the completion of
a voltage conversion cycle the LM96194 performs limit com-
parisons based on average VID values and not instantaneous
values. The upper limit is determined by adding the upper limit
offset to the average voltage indicated by VID. The lower limit
is determined by subtracting the lower limit offset from aver-
age voltage indicated by VID. If the AD_IN4 voltage falls
outside the upper and lower limits, an error event is generat-
ed. Dynamic and static comparisons are performed once
every 100 ms. The averaging time interval is 1.5 ms.
If at any time during the Vccp sampling window, the VID code
indicates that the VRD/VRM should turn off its output, the dy-
namic Vccp checking is disabled for that sample.
The comparison accuracy is ±25 mV, therefore the compari-
son limits must be set to include this error. Since the Vccp
voltage may be in the process of settling to a new value (due
to a VID change), this settling should be taken into account
when setting the upper and lower limit offsets.
The LM96194 has a limitation on the upper limit voltage for
dynamic Vccp checking. The upper limit cannot exceed
1.5875V. If the sum of the voltage indicated by VID and the
upper offset voltage exceed 1.5875, the upper limit checking
is disabled.
Pin 17 has a dual purpose. When VRD10 mode is selected
they can be used as general purpose inputs whose state is
reflected the BMC and Host Error Status registers. In the other
VRD modes they are used as a VID6 input.
12.10 MONITORING ANALOG TEMPERATURE SENSORS
The AD_IN8 reading can be routed to the fan control logic to
facilitate the use of external temperature sensors such as the
LM60. When these inputs are used for temperature sensing
the digital output returned is in signed format, that is the MSb
is inverted.
The following table lists critical parameters necessary for con-
verting the binary data to temperature.
The following table lists the equations to use for converting
the AD_IN8 Digital Value (DV) to a temperature value.
The following table lists the ideal values generated when us-
ing the LM60 at different temperatures.
Input V NOM
AD_
IN8
Input
AD_IN8
0
25
30
35
Temp
(¼ scale)
0.309
LM60 Equation
(DV + 40.18) × 0.7725
0.424
0.5803
0.6115
0.6428
LM60
Ideal
Vout
1.2360
256) V
Scale
(code
Full
-40.18
-8
-1
5
code V
1.2288
254.5
Decimal
Signed
AD_IN8 Reading
LM50 Equation
(DV + 24.44) × 0.4828
/LSb
mV
4.8 0.7725 0.4828
LM60
D8
F8
FF
5
/LSb
deg
Signed
Hex
LM50
/LSb
deg
15
The following table lists the expected ideal digital values when
using the LM50.
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
0
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
Temp
Temp
0.6740
0.7053
0.7365
0.7678
0.7990
0.8303
0.8615
0.8928
0.9240
0.9553
0.9865
1.0178
1.0490
1.0803
1.1115
1.1428
1.1740
1.2053
1.2365
0.5
0.7500
0.8000
0.8500
0.9000
0.9500
1.0000
1.0500
1.1000
1.1500
1.2000
1.2500
1.3000
1.3500
1.4000
1.4500
1.5000
1.5500
1.6000
1.6500
1.7000
1.7500
1.8000
LM60
LM50
Ideal
Ideal
Vout
Vout
12
18
25
31
37
44
50
57
63
70
76
83
89
96
102
109
115
122
127
-24.44
27
38
48
58
69
79
89
100
110
121
127
127
127
127
127
127
127
127
127
127
127
127
Decimal
Decimal
Signed
Signed
AD_IN8 Reading
AD_IN8 Reading
C
12
19
1F
25
2C
32
39
3F
46
4C
53
59
60
66
6D
73
7A
7F
E8
1B
26
30
3A
45
4F
59
64
6E
79
7F
7F
7F
7F
7F
7F
7F
7F
7F
7F
7F
7F
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Signed
Signed
Hex
Hex