THMC50

REMOTE/LOCAL TEMPERATURE MONITOR AND

FAN CONTROLLER WITH SMBus INTERFACE

SLIS090 – JULY 1999

26

POST OFFICE BOX 655303

PRINCIPLES OF OPERATION

register 0x4C interrupt status register 1 mirror

power-on default <7:0> = 00h

BIT

NAME

READ/WRITE

DESCRIPTION

0

Ambient temperature error

Read only

A 1 indicates one of the ambient temperature limits has been exceeded.

1

Reserved

Read only

Undefined (reserved for remote thermal diode 2 temperature error)

2

Reserved

Read only

Undefined (reserved for remote thermal diode 2 fault)

3

Reserved

Read only

Undefined

4

GPI input

Read only

A 1 indicates that the GPI terminal is asserted. The polarity of the GPI terminal is

determined by GPI invert (bit 6) in the configuration register. For example, if GPI invert is

cleared, then this bit is 1 when the GPI terminal is high (1); this bit is 0 when the GPI

terminal is low (0). If GPI invert is set, then this bit is 1 when the GPI terminal is low (0); this

bit is 0 when the GPI terminal is high (1). Note: The state of GPI is not latched; this bit

simply reflects the state or inverted state of the GPI terminal. If this bit is 1, reading this

register does not clear it to 0.

5

Remote temperature error

Read only

A 1 indicates one of the remote thermal diode limits has been exceeded.

6

THERM input

Read only

A 1 indicates that the thermal overload (THERM) line has been asserted externally.

7

Remote diode fault

Read only

A 1 indicates either a short or open circuited fault on the remote thermal diode inputs.

register 0x13 - 0x4A value RAM

power-on default are undefined unless stated otherwise

ADDRESS

READ/WRITE

DESCRIPTION

0x13

Read/write

Programmable ambient temperature automatic trip point

≥ default 70°C. This register can only be written if the

write-once bit in the configuration register (0x40, bit 3) has not been set.

0x14

Read/write

Programmable remote thermal diode automatic trip point

≥ default 100°C. This register can only be written if the

write-once bit in the configuration register (0x40, bit 3) has not been set.

0x15

Read/write

Manufacturer’s test register

0x17

Read only

Default ambient temperature automatic trip point

≥ 70° C

0x18

Read only

Default remote thermal diode automatic trip point

≥ 100°C

0x19

Read/write

Analog output (defaults to 0x00)

0x20

N/A

Reserved (for future second remote thermal diode temperature)

0x26

Read only

Remote thermal diode temperature

0x27

Read only

Ambient temperature

0x2B

N/A

Reserved (for future second remote thermal diode high limit)

0x2C

N/A

Reserved (for future second remote thermal diode low limit)

0x37

Read/write

Remote thermal diode high limit

0x38

Read/write

Remote thermal diode low limit

0x39

Read/write

Ambient temperature high limit

0x3A

Read/write

Ambient temperature low limit

0x3E

Read only

Company ID number (0x49)

0x3F

Read only

Stepping ID number and THMC50 version number

0x44

Read/write

For manufacturer’s test use (reads or writes have unpredictable results)

0x47

Read/write

For manufacturer’s test use (reads or writes have unpredictable results)

0x4A

Read/write

For manufacturer’s test use (reads or writes have unpredictable results)

NOTE: All unspecified locations are considered as reserved and should not be accessed. Unpredictable results may occur.