Microchip Technology MCP9800DM-DL2 Data Sheet
MCP9800/1/2/3
DS21909D-page 20
2010 Microchip Technology Inc.
5.3.3
TEMPERATURE HYSTERESIS
REGISTER (T
REGISTER (T
HYST
)
The MCP9800/1/2/3 has a 16-bit read/write
Temperature Hysteresis register that contains a 9-bit
data in two’s compliment format. This register is used
to set a hysteresis for the T
Temperature Hysteresis register that contains a 9-bit
data in two’s compliment format. This register is used
to set a hysteresis for the T
SET
limit. Therefore, the data
represents a minimum temperature limit. If the ambient
temperature drifts below the specified limit, the
MCP9800/1/2/3 asserts an alert output (refer to
temperature drifts below the specified limit, the
MCP9800/1/2/3 asserts an alert output (refer to
This register uses the nine Most Significant bits (MSbs)
and all other bits are “don’t cares”.
The power-up default value of T
and all other bits are “don’t cares”.
The power-up default value of T
HYST
register is 75°C,
or <0100 1011 0>b in binary.
REGISTER 5-4:
TEMPERATURE HYSTERESIS REGISTER (T
HYST
) – ADDRESS <
0000 0010
>b
Upper Half:
R/W-0
R/W-1
R/W-0
R/W-0
R/W-1
R/W-0
R/W-1
R/W-1
Sign
2
6
°C
2
5
°C
2
4
°C
2
3
°C
2
2
°C
2
1
°C
2
0
°C
bit 15
bit 8
Lower Half:
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
2
-1
°C
0
0
0
0
0
0
0
bit 7
bit 0
Legend:
R = Readable bit
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown