Command Se-

lect Address

Power On Default State

Register Name

Register Function

mal

5Ch-6Fh and

F0h-FDh

Reserved for Future Use

FEh

0000 0001

1

RMID

Read Manufacturers ID

FFh

RSR

Read Stepping or Die

Revision Code

2.2 LOCAL and D1, D2 and D3 REMOTE TEMPERATURE REGISTERS (LT, D1RT, D2RT, and D3RT)

(Read Only Address 00h, 01h, 30h and 31h):

D7

D6

D5

D4

D3

D2

D1

D0

MSB

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

LSB

D7–D0: Temperature Data. One LSB = 1˚C. Two’s complement format.

2.3 STATUS REGISTERS 1 and 2

2.3.1 Status Register 1 (SR1) (Read Only Address 02h):

D7

D6

D5

D4

D3

D2

D1

D0

0

LHIGH

0

D2RHIGH

0

D2OPEN

D2CRIT

LCRIT

Power up default is with all bits “0” (zero).

D0: LCRIT: When set to a 1 indicates an Local Critical Temperature alarm.

D1: D2CRIT: When set to a 1 indicates a Remote Diode 2 Critical Temperature alarm.

D2: D2OPEN: When set to 1 indicates a Remote Diode 2 disconnect.

D4: D2RHIGH: When set to 1 indicates a Remote Diode 2 HIGH Temperature alarm.

D6: LHIGH: When set to 1 indicates a Local HIGH Temperature alarm.

D7, D5, and D3: These bits are always set to 0 and reserved for future use.

Status Register 2

2.3.2 Status Register 2 (SR2) (Read Only Address 35h):

D7

D6

D5

D4

D3

D2

D1

D0

D1RHIGH

0

D1OPEN

D3RHIGH

0

D3OPEN

D3CRIT

D1CRIT

Power up default is with all bits “0” (zero).

D0: D1CRIT, when set to 1 indicates a Remote Diode 1 Critical Temperature alarm.

D1: D3CRIT, when set to 1 indicates a Remote Diode 3 Critical Temperature alarm.

D2: D3OPEN, when set to 1 indicates a Remote Diode 3 disconnect.

D4: D3RHIGH, when set to 1 indicates a Remote Diode 3 HIGH Temperature alarm.

D5: D1OPEN, when set to 1 indicates a Remote Diode 1 disconnect.

D7: D1RHIGH, when set to 1 indicates a Remote Diode 1

HIGH Temperature alarm.

D6, and D3: These bits are always set to 0 and reserved for future use.

2.4 MANUFACTURERS ID REGISTER

(Read Address FEh) Default value 01h.

2.5 CONFIGURATION REGISTER

(Read Address 03h/Write Address 09h):

D7

D6

D5

D4

D3

D2

D1

D0

INT mask

0D1

T_CRIT_A

mask

D2

T_CRIT_A

mask

D3

T_CRIT_A

mask

Local

T_CRIT_A

mask

INT Inversion

0

Power up default is with all bits “0” (zero).

D7: INT mask: When set to 1 INT interrupts are masked.

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