LM75
1.0 Functional Description
1.11 POINTER REGISTER
(Continued)
(Selects which registers will be read from or written to):
P7
0
P6
0
P5
0
P4
0
P3
0
P2
0
P1
P0
Register
Select
P0-P1: Register Select:
P1
0
0
1
1
P2–P7: Must be kept zero.
1.12 TEMPERATURE REGISTER
(Read Only):
D15
MSB
D14
Bit 7
D13
Bit 6
D12
Bit 5
D11
Bit 4
D10
Bit 3
D9
Bit 2
D8
Bit 1
D7
LSB
D6
X
D5
X
D4
X
D3
X
D2
X
D1
X
D0
X
P0
0
1
0
1
Register
Temperature (Read only) (Power-up default)
Configuration (Read/Write)
T
HYST
(Read/Write)
T
OS
(Read/Write)
D0–D6: Undefined
D7–D15: Temperature Data. One LSB = 0.5˚C. Two’s
complement format.
1.13 CONFIGURATION REGISTER
(Read/Write):
D7
0
D6
0
D5
0
D4
Fault Queue
D3
D2
O.S.
Polarity
Power up default is with all bits “0” (zero).
D0: Shutdown: When set to 1 the LM75 goes to low power
shutdown mode.
D1: Comparator/Interrupt mode: 0 is Comparator mode, 1 is
Interrupt mode.
D2: O.S. Polarity: 0 is active low, 1 is active high. O.S. is an
open-drain output under all conditions.
D4
0
0
1
1
D3
0
1
0
1
2
4
6
D3–D4: Fault Queue: Number of faults necessary to detect
before setting O.S. output to avoid false tripping due to
noise. Faults are determind at the end of a conversion.
Conversions take about 100 ms, typically, to complete.
D1
Cmp/Int
D0
Shutdown
Number of Faults
1 (Power-up default)
D5–D7: These bits are used for production testing and must
be kept zero for normal operation.
1.14 T
HYST
AND T
OS
REGISTER
(Read/Write):
D15
MSB
D14
Bit 7
D13
Bit 6
D12
Bit 5
D11
Bit 4
D10
Bit 3
D9
Bit 2
D8
Bit 1
D7
LSB
D6
X
D5
X
D4
X
D3
X
D2
X
D1
X
D0
X
D0–D6: Undefined
D7–D15: T
HYST
Or T
OS
Trip Temperature Data. Power up
default is T
OS
= 80˚C, T
HYST
= 75˚C.
11
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