LM63

www.ti.com

SNAS190E – SEPTEMBER 2002 – REVISED MAY 2013

POWER-ON RESET (POR) DEFAULT STATES

For information on the POR default states, see REGISTER MAP IN FUNCTIONAL ORDER.

TEMPERATURE DATA FORMAT

Temperature data can only be read from the Local and Remote Temperature registers. The High, Low and

T_CRIT setpoint registers are Read/Write.

Remote temperature data is represented by an 11-bit, two's complement word with a Least Significant Bit (LSB)

equal to 0.125°C. The data format is a left justified 16-bit word available in two 8-bit registers:

DIGITAL OUTPUT

TEMPERATURE

BINARY

HEX

+125°C

0111 1101 0000 0000

7D00

+25°C

0001 1001 0000 0000

1900

+1°C

0000 0001 0000 0000

0100

+0.125°C

0000 0000 0010 0000

0020

0°C

0000 0000 0000 0000

0000

−0.125°C

1111 1111 1110 0000

FFE0

−1°C

1111 1111 0000 0000

FF00

−25°C

1110 0111 0000 0000

E700

−55°C

1100 1001 0000 0000

C900

Local Temperature data is represented by an 8-bit, two's complement byte with an LSB equal to 1°C:

DIGITAL OUTPUT

TEMPERATURE

BINARY

HEX

+125°C

0111 1101

7D

+25°C

0001 1001

19

+1°C

0000 0001

01

0°C

0000 0000

00

−1°C

1111 1111

FF

−25°C

1110 0111

E7

−55°C

1100 1001

C9

OPEN-DRAIN OUTPUTS

The SMBDAT, ALERT, and PWM outputs are open-drain outputs and do not have internal pullups. A “High” level

will not be observed on these pins until pullup current is provided by an internal source, typically through a pullup

resistor. Choice of resistor value depends on several factors but, in general, the value should be as high as

possible consistent with reliable operation. This will lower the power dissipation of the LM63 and avoid

temperature errors caused by self-heating of the device. The maximum value of the pullup resistor to provide the

2.1 V high level is 88.7 k

Ω.

Copyright © 2002–2013, Texas Instruments Incorporated

Submit Documentation Feedback

13

Product Folder Links: LM63