2.5 DEVICE ID (Addr: 000 010; 02h)

Reg

Add

Register

Name

R/

W

P

O

R

Val

Bit

15

MSb

Bit

14

Bit

13

Bit

12

Bit

11

Bit

10

Bit

9

Bit

8

Bit

7

Bit

6

Bit

5

Bit

4

Bit

3

Bit

2

Bit

1

Bit

0

LSb

000 010 Device ID

R

22h

RevID

DeviceID

0000000000100010

The device ID is defined by the manufacturer of the device and is unique for each device produced by a manufacturer. Bits 15-11

identify the revision number of the die and will be incremented upon revision of the device.

Bit

Type

Description

10-0

RO

DeviceID (Device ID Value) A fixed value that identifies the device.

15-11

RO

RevID (Revision ID Value) A fixed value that identifies the device revision.

2.6 CAPABILITIES FIXED (Addr: 000 011; 03h)

Reg

Add

Register

Name

R/

W

P

O

R

Val

Bit

15

MSb

Bit

14

Bit

13

Bit

12

Bit

11

Bit

10

Bit

9

Bit

8

Bit

7

Bit

6

Bit

5

Bit

4

Bit

3

Bit

2

Bit

1

Bit

0

LSb

000 011

Capabilities

Fixed

R

21h

Reserved

FuncDescriptor2

FuncDescriptor1

0000000000100001

The value of this register defines the capabilities of the LM40. The LM40 supports two functions, that of Temperature

Measurement type (Function 1) and Voltage-Only Measurement type (Function 2). Please refer to the SensorPath specification

for further details on other FuncDescriptor values.

2.7 DEVICE STATUS (Addr: 000 100; 04h)

This register is set to the reset value by a Device Reset.

Reg Add

Register Name

R/

W

P

O

R

Val

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

LSb

000 100

Device Status

R

0h

BER

Res

ERF2

ERF1

Res

SF2

SF1

00

0

Bit

Type

Description

0RO

SF1 (Status Function 1) This bit is set by a Function Event within Function 1. Event details are function

dependent and are described within the function. SF1 is cleared by Device Reset or by handling the event

within the Temperature Measurement Function (see Section 2.9 for further details).

0: Status flag for Function 1 is inactive (no event).

1: Status flag for Function 1 is active indicating that a Function Event has occurred.

1RO

SF2 (Status Function 2) Same as SF1 for Function 2, Voltage-Only Measurement Function. (see Section

2.10 for further details)

3-2

RO

Reserved. Will always read "0".

4RO

ERF1 (Error Function 1) This bit is set in response to an error indication within Function 1. ERF1 is cleared

by Device Reset or by handling the error condition within the Temperature Measurement Function (see

Section 2.9 for further details).

0: No error occurred in Function 1.

1: Error occurred in Function 1.

5RO

ERF2 (Error Function 2) Same as ERF1 for Function 2, Voltage-Only Measurement Function. (see Section

2.10 for further details)

6RO

Reserved. Will always read "0".

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