2.1 STATUS REGISTER

(Read Only Address 02h):

D7

D6

D5

D4

D3

D2

D1

D0

Busy

Reserved

R2TME

R1TME

RD2M

RD1M

000

Bits

Name

Description

7

Busy

When set to "1" the part is converting.

6-4

Reserved

Reports "0" when read.

3

Remote 2 TruTherm Mode

Enabled (R2TME)

When set to "1" indicates that the TruTherm Mode has been activated

for Remote diode 2. After being enabled TruTherm Mode will take at

most one conversion cycle to be fully active. This bit will be set even if

the diode is desconnected.

2

Remote 1 TruTherm Mode

Enabled (R1TME)

When set to "1" indicates that the TruTherm Mode has been activated

for Remote diode 1. After being enabled TruTherm Mode will take at

most one conversion cycle to be fully active. This bit will be set even if

the diode is disconnected.

1

Remote Diode 2 Missing (RD2M)

When set to "1" Remote Diode 2 is missing. (See Section 1.6 for

further details.) Temperature Reading is FFE0h which converts to

255.875 ˚C if unsigned format is selected or 8000h which converts to

–128.000 ˚C if signed format is selected. Note, connecting a 3904

transistor to Remote 2 inputs with TruTherm mode active may also

cause this bit to be set.

0

Remote Diode 1 Missing (RD1M)

When set to "1" Remote Diode 1 is missing. (See Section 1.6 for

further details.) Temperature Reading is FFE0h which converts to

255.875 ˚C if unsigned format is selected or 8000h which converts to

–128.000 ˚C if signed format is selected. Note, connecting a 3904

transistor to Remote 1 inputs with TruTherm mode active may also

cause this bit to be set.

2.2 CONFIGURATION REGISTER

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

D7

D6

D5

D4

D3

D2

D1

D0

0

RUN/STOP

CR1

CR0

0

R2DF

R1DF

0

Bits

Name

Description

7

Reserved

Reports "0" when read.

6

RUN/STOP

Logic 1 disables the conversion and puts the part in standby mode.

Conversion can be activated by writing to one-shot register.

5-4

Conversion Rate (CR1:CR0)

00: continuous mode 76.5 ms, 13.1 Hz (typ), when TruTherm Mode is

disabled (Diode Equation) for both remote channels; 77.8 ms, 12.9 Hz

(typ), when TruTherm Mode is enabled (Transistor Equation) for one

remote channel.

01: converts every 182 ms, 5.5 Hz (typ)

10: converts every 1 second, 1 Hz (typ)

11: converts every 2.7 seconds, 0.37 Hz (typ)

3

Reserved

Reports "0" when read.

2

Remote 2 Data Format (R2DF)

Logic 0: unsigned Temperature format (0 ˚C to +255.875 ˚C)

Logic 1: signed Temperature format (-128 ˚C to +127.875 ˚C)

1

Remote 1 Data Format (R1DF)

Logic 0: unsigned Temperature format (0 ˚C to +255.875 ˚C)

Logic 1: signed Temperature format (-128 ˚C to +127.875 ˚C)

0

Reserved

Reports "0" when read.

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

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