Rainbow Electronics MAX6641 - Manual (Page 6)

MAX6641
SMBus-Compatible Temperature Monitor with
Automatic PWM Fan-Speed Controller
6 _______________________________________________________________________________________
READ/
WRITE
REGISTER
ADDRESS
POR
STATE
FUNCTION/
NAME
D7 D6 D5 D4 D3 D2 D1 D0
R 00h 0000 0000
Read remote
(external)
temperature
MSB
(+128 °C)
(+64 °C) (+32 °C) (+16 °C) (+8°C) (+4 °C) (+2 °C)
LSB
(+1 °C)
R 01h 0000 0000
Read local
(internal)
temperature
MSB
(+128 °C)
(+64 °C) (+32 °C) (+16 °C) (+8°C) (+4 °C) (+2 °C)
LSB
(+1 °C)
R/W 02h 0000 00xx
Configuration
byte
Reserved
set to 0 Reserved
set to 0
Timeout: 0 =
enabled, 1 =
disabled
Fan
PWM
invert
Min duty
cycle:
0 = 0%,
1 = fan-
start duty
cycle
Spin-up
disable
X X
R/W 03h 0110 1110
Remote-diode
temperature
OT limit
MSB
(+128 °C)
(+64 °C) (+32 °C) (+16 °C) (+8°C) (+4 °C) (+2 °C)
LSB
(+1 °C)
R/W 04h 0101 0000
Local-diode
temperature
OT limit
MSB
(+128 °C)
(+64 °C) (+32 °C) (+16 °C) (+8°C) (+4 °C) (+2 °C)
LSB
(+1 °C)
R 05h 00xx xxxx OT status
Remote 1
= fault
Local 1 =
fault
X X X X X X
R/W 06h 00xx xxxx OT mask
Remote 1
= masked
Local 1 =
masked
X X X X X X
R/W 07h
0110 000x
(96 = 40%)
Fan-start duty
cycle
MSB
(128/240)
(64/240) (32/240) ( 16/240) (8/240) (4/240)
LSB
(2/240)
X
R/W 08h
1111 000x
(240 =
100%)
Fan maximum
duty cycle
MSB
(128/240)
(64/240) (32/240) ( 16/240) (8/240) (4/240)
LSB
(2/240)
X
R/W 09h 0000 000x
Fan target duty
cycle
MSB
(128/240)
(64/240) (32/240) ( 16/240) (8/240) (4/240)
LSB
(2/240)
X
R 0Ah 0000 000x
Fan
instantaneous
duty cycle
MSB
(128/240)
(64/240) (32/240) ( 16/240) (8/240) (4/240)
LSB
(2/240)
X
R/W 0Bh 0000 0000
Remote-diode
fan-start
temperature
MSB
(+128 °C)
(+64 °C) (+32 °C) (+16 °C) (+8°C) (+4 °C) (+2 °C)
LSB
(+1 °C)
Table 1. Register Functions