STDS75

Functional description

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3.1.2

Configuration register

The configuration register is used to store the device settings such as device operation

mode, OS/INT operation mode, OS/INT polarity, and OS/INT fault queue.

The configuration register allows the user to program various options such as conversion

resolution (see Table 7), thermostat fault tolerance, thermostat polarity, thermostat operating

mode, and shutdown mode. The user has READ/WRITE access to all of the bits in the

configuration register except the MSB (bit7), which is reserved as a “Read only” bit (see

Table 6). The entire register is volatile and thus powers-up in its default state only.

Table 6.

Configuration register format

Byte

MSB

LSB

Bit7

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

Bit0

STDS75

Reserved

RC1

RC0

FT1

FT0

POL

M

SD

Default

00000000

Keys:

SD = shutdown control bit

FT1 = fault Tolerance1 bit

1.

Indicates operation mode; 0 = comparator mode, and 1 = interrupt mode (see Comparator mode on

page 12 and Interrupt mode on page 13).

RC0 = resolution Conversion0 bit

2.

The OS/INT is active-low ('0').

RC1 = resolution Conversion1 bit

FT0 = fault Tolerance0 bit

Bit7 = must be set to '0.' Reserved

Table 7.

Programmable resolution configurations

RC1

RC0

Resolution

Conversion time

Remarks

0

0

9-bit

0.5°C

150 ms

Default resolution

0

1

10-bit

0.25°C

300 ms

1

0

11-bit

0.125°C

600 ms

1

1

12-bit

0.0625°C

1200 ms