1.11 POINTER REGISTER

(Selects which registers will be read from or written to):

P7

P6

P5

P4

P3

P2

P1

P0

0

00000

Register

Select

P0-P1: Register Select:

P1

P0

Register

0

0

Temperature (Read only) (Power-up default)

0

1

Configuration (Read/Write)

10

T

11

T

P2–P7: Must be kept zero.

1.12 TEMPERATURE REGISTER

(Read Only):

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

MSB

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

LSB

XXXXXX

X

D0–D6: Undefined

D7–D15: Temperature Data. One LSB = 0.5˚C. Two’s

complement format.

1.13 CONFIGURATION REGISTER

(Read/Write):

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

Fault Queue

O.S.

Cmp/Int

Shutdown

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.

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.

D4

D3

Number of Faults

0

0

1 (Power-up default)

01

2

10

4

11

6

D5–D7: These bits are used for production testing and must

be kept zero for normal operation.

1.14 T

(Read/Write):

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

MSB

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

LSB

XXXXXX

X

D0–D6: Undefined

D7–D15: T

default is T

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