Analog Input Voltage Mapping

Sensor

Number

(SNUM)

Voltage Input

Input Voltage

for Nominal

Reading

(code 384 or

180h)

Maximum

Input Voltage

(code 510.5)

Register

Reading at

Maximum

Voltage

Minimum

Input Voltage

Register

Reading at

Minimum

Voltage

Resolution

0

+2.5V

2.5V

3.32V to 6V

1FFh

-0.5V to

3.26mV

00h

6.51mV

1

+1.2V

1.2V

1.6V to 6V

1FFh

-0.5V to

2.63mV

00h

5.86mV

2

+3.3V_SBY

(V+)

3.3V

4.39V to 6V

1FFh

3.0V

15Dh

8.59mV

3

+5V

5V

6.65V

1FFh

-0.5V to

6.51mV

00h

13.02mV

4

+12V

12V

15.95V to 16V 1FFh

-0.5V to

15.63mV

00h

31.25mV

2.10.4 Voltage Control (Addr: 010 010; 12h)

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

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

010 010

Voltage

Control

R/

W

1Fh

Reserved

EN4 EN3 EN2 EN1 EN0 ATE

Low Rate Function

(Read Only)

00000

11111

Bit

Type

Description

4-0

RO

Low Rate Function

This function is not supported by the LM40 and therefore this field is read only.

5

R/W

ATE (Attention Enable). When set, this bit enables an Attention Request signal to be generated by the

LM40, if one or more EN0-EN4 bits of this register are set.

0: Attention Request disabled (from enabled Temperature Sensor- default)

1: Attention Request enabled

6

R/W

EN0 (Enable Sensor 0). When this bit is set, the Voltage Sensor 0 is enabled for voltage measurements.

0: Voltage Sensor disabled (default)

1: Voltage Sensor enabled

10-7

R/W

EN1-EN4 (Enable Sensor 1-4). Same as EN0 for Voltage sensors 1-4.

0: Voltage Sensor disabled (default)

1: Voltage Sensor enabled

15-11

RO

Reserved. Will always read "0".

2.11 CONVERSION RATE (Addr: 100 000; 20h)

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

100 000

Conversion Rate

R/

W

2h

Reserved

CR1

CR0

000000

Bit

Type

Description

1-0

RO

CR0 and CR1 (Conversion Rate bits 0 and 1)

These bits control the conversion rate of the LM40 for

more details see Table Conversion Rate Control and desciption below.

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