MAX1617 ON Semiconductor, MAX1617 Datasheet - Page 11

• Manufacturer Part Number: MAX1617
• Description: SMBus Temperature Sensor with Internal and External Diode Input
• Manufacturer: ON Semiconductor

Status Register (Status)
NOTE: All status bits are cleared after a read operation is
performed on STATUS. The EXT_TEMP register will read +127 C
if an external diode “open” is detected.
Register Set Summary:
*NOTE: The INT_TEMP and EXT_TEMP register immediately will be updated by the A/D converter after POR. If STBY is low at power–up,
Name
INT_TEMP
EXT_TEMP
STATUS
CONFIG
CONV_RATE
INT_HLIM
INT_LLIM
EXT_HLIM
EXT_LLIM
MFR_ID
MFR_REV
CRITICAL
Busy
D[1:0]
Bit(s)
D[7]
D[7]
D[6]
D[5]
D[4]
D[3]
D[2]
The MAX1617’s register set is summarized in the following table. All registers are 8–bits wide.
INT_TEMP and EXT_TEMP will remain in POR state (0000 0000b).
**MFR_REV will sequence 01h, 02h, 03h, etc. by mask changes.
***CRITICAL only can be written via the CRIT[1:0] pins. It cannot be accessed through the SMBus port.
Flag1 Flag2 Flag3 Flag4 Flag5 Flag6
D[6]
State
POR
0
0
0
0
0
0
0
D[5]
Function
Signal A/D
converter is busy.
Interrupt flag for
INT_HLIM event
Interrupt flag for
INT_LLIM event
Interrupt flag for
EXT_HLIM event
Interrupt flag for
EXT_LLIM event
External diode
“fault” flag
Reserved —
Always returns
zero.
Description
Internal sensor temperature (2’s complement)
External sensor temperature (2’s complement)
STATUS register
CONFIG register
A/D conversion rate register
Internal high limit (2’s complement)
Internal low limit (2’s complement)
External high limit (2’s complement)
External low limit (2’s complement)
ASCII for letter “T”
Serial device revision #
CRITICAL limit (2’s complement)
D[4]
D[3]
Operation*
1 = A/D busy,
0 = A/D idle
1 = interrupt occurred,
0 = none
1 = interrupt occurred,
0 = none
1 = interrupt occurred,
0 = none
1 = interrupt occurred,
0 = none
1 = external diode fault
0 = external diode OK
N/A
D[2]
D[1]
served
http://onsemi.com
D[0]
Re-
MAX1617
11
Manufacturer’s Identification Register (MFR_ID),
8–Bits, Read Only:
Manufacturer’s Identification Register (MFR_ID)
Manufacturer’s Revision Register (MFR_REV),
8–Bits, Read Only:
Manufacturer’s Revision Register (MFR_REV)
MSB
MSB
D[7]
D[7]
D[6]
D[6]
X
X
0000 0000b*
0000 0000b*
0000 0000b
0000 0000b
0000 0010b
0101 0100b
1100 1001b
1100 1001b
POR State
0111 1111b
0111 1111b
N/A
**
D[5]
D[5]
X
X
D[4]
D[4]
X
X
D[3]
D[3]
X
X
Read
D[2]
D[2]
X
X
D[1]
D[1]
X
X
Write
***
D[0]
LSB
D[0]
LSB