STLM75

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 operation mode, OS polarity, and OS fault queue.

The configuration register allows the user to program various options such as 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 5.

Register pointers selection summary

Pointer

value (H)

P1

P0

Name

Description

Width

(bits)

Type

(R/W)

Power-

on

default

Comments

00

0

0

TEMP

Temperature

register

16

Read-

only

N/A

To store measured

temperature data

01

0

1

CONF

Configuration

register

8R/W

00

02

1

0

Hysteresis

register

16

R/W

4B00

Default = 75°C

03

1

1

Over-

temperature

shutdown

16

R/W

5000

Set point for over-

temperature shutdown

Table 6.

Configuration register format

Byte

MSB

LSB

Bit7

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

Bit0

STLM75

Reserved

0

0

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 and

Interrupt mode on page 13).

Bit 5 = must be set to '0'.

2.

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

Bit 6 = must be set to '0'.

FT0 = fault tolerance0 bit

Bit 7 = must be set to '0'. Reserved.