SE97 Datasheet, PDF (30/54 Pages) NXP Semiconductors – DDR memory module temp sensor with integrated SPD, 3.3 V

NXP Semiconductors
SE97
DDR memory module temp sensor with integrated SPD, 3.3 V
8.5.2 Lower Boundary Alarm Trip register (16-bit read/write)
The value is the lower threshold temperature value for Alarm mode. The data format is
2’s complement with bit 2 = 0.25 °C. RFU bits will always report zero. Interrupts will
respond to the presently programmed boundary values. If boundary values are being
altered in-system, it is advised to turn off interrupts until a known state can be obtained to
avoid superfluous interrupt activity.
Table 17.
Bit
Symbol
Default
Access
Bit
Symbol
Default
Access
Lower Boundary Alarm Trip register bit allocation
15
14
13
12
11
RFU
SIGN
0
0
0
0
0
R
R
R
R/W
R/W
7
6
5
4
3
LBT
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
10
9
8
LBT
0
0
0
R/W
R/W
R/W
2
1
0
RFU
0
0
0
R/W
R
R
Table 18. Lower Boundary Alarm Trip register bit description
Bit
Symbol
Description
15:13 RFU
reserved; always ‘0’
12
SIGN
Sign (MSB)
11:2
LBT
Lower Boundary Alarm Trip Temperature (LSB = 0.25 °C)
1:0
RFU
reserved; always ‘0’
8.5.3 Critical Alarm Trip register (16-bit read/write)
The value is the critical temperature. The data format is 2’s complement with
bit 2 = 0.25 °C. RFU bits will always report zero.
Table 19.
Bit
Symbol
Default
Access
Bit
Symbol
Default
Access
Lower Boundary Alarm Trip register bit allocation
15
14
13
12
11
RFU
SIGN
0
0
0
0
0
R
R
R
R/W
R/W
7
6
5
4
3
CT
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
10
9
8
CT
0
0
0
R/W
R/W
R/W
2
1
0
RFU
0
0
0
R/W
R
R
Table 20. Critical Alarm Trip register bit description
Bit
Symbol
Description
15:13 RFU
reserved; always ‘0’
12
SIGN
Sign (MSB)
11:2
CT
Critical Alarm Trip Temperature (LSB = 0.25 °C)
1:0
RFU
reserved; always ‘0’
SE97_5
Product data sheet
Rev. 05 — 6 August 2009
© NXP B.V. 2009. All rights reserved.
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