2.8 REMOTE TEMPERATURE OFFSET REGISTERS (RTOHB and RTOLB)

(Read / Write Address 11h):

BIT

D7

D6

D5

D4

D3

D2

D1

D0

Value

SIGN

64

32

16

8

4

2

1

For RTOHB: Remote Temperature Offset High Byte. Power-on default is LHIGH = RHIGH = 0˚C. 1 LSB = 1˚C. Two’s complement

format.

(Read / Write Address 12h):

BIT

D7

D6

D5

D4

D3

D2

D1

D0

Value

0.5

0.25

0.125

0000

0

For RTOLB: Remote Temperature Offset High Byte. Power-on default is 0˚C. 1 LSB = 0.125˚C. Two’s complement format.

The offset value written to these registers will automatically be added to or subtracted from the remote temperature measurement

that will be reported in the Remote Temperature registers.

2.9 LOCAL and REMOTE T_CRIT REGISTERS (RCS and LCS)

(Read / Write Address 20h, 19h):

BIT

D7

D6

D5

D4

D3

D2

D1

D0

Value

SIGN

64

32

16

8

4

2

1

D7–D0: T_CRIT setpoint temperature data. Local power-on default is T_CRIT = 85˚C. Remote power-on default is T_CRIT =

110˚C (+126˚C actual remote diode temperature). 1 LSB = 1˚C, two’s complement format.

2.10 T_CRIT HYSTERESIS REGISTER (TH)

(Read and Write Address 21h):

BIT

D7

D6

D5

D4

D3

D2

D1

D0

Value

16

842

1

D7–D0: T_CRIT Hysteresis temperature. Power-on default is TH = 10˚C. 1 LSB = 1˚C, maximum value = 31.

2.11 FILTER and ALERT CONFIGURE REGISTER

(Read and Write Address BFh):

BIT

D7

D6

D5

D4

D3

D2

D1

D0

Value

00000

Filter Level

ALERT

Configure

D7-D3: is not defined defaults to "0".

D2-D1: input filter setting as defined the table below:

D2

D1

Filter Level

0

0

No Filter

0

1

Level 1

1

0

Level 1

1

1

Level 2

Level 2 sets maximum filtering.

D0: when set to "1" comparator mode is enabled.

2.12 MANUFACTURERS ID REGISTER

(Read Address FEh) Default value 01h.

2.13 DIE REVISION CODE REGISTER

(Read Address FFh) The LM99 version has a default value 31h or 49 decimal. The LM99-1 version has a default value of 34h or

52 decimal. This register will increment by 1 every time there is a revision to the die by National Semiconductor.

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