LM75BDP NXP Semiconductors, LM75BDP Datasheet - Page 9

• Manufacturer Part Number: LM75BDP
• Description: IC, TEMP SENSOR, DIGITAL, 8-TSSOP
• Manufacturer: NXP Semiconductors

Specifications of LM75BDP

• Ic Output Type: Digital
• Sensing Accuracy Range: ± 3°C
• Supply Current: 100µA
• Supply Voltage Range: 2.8V To 5.5V
• Resolution (bits): 11bit
• Sensor Case Style: TSSOP
• No. Of Pins: 8
• Base Number: 75
• Temperature Sensing Range: -55°C To +125°C
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

NXP Semiconductors
LM75B_2
Product data sheet
7.4.4 Overtemperature shutdown threshold (Tos) and hysteresis (Thyst) registers
Table 9.
For 9-bit Temp data application in replacing the industry standard LM75, just use only
9 MSB bits of the two bytes and disregard 7 LSB of the LSByte. The 9-bit Temp data with
0.5 C resolution of the LM75B is defined exactly in the same way as for the standard
LM75 and it is here similar to the Tos and Thyst registers.
The only MSByte of the temperature can also be read with the use of a one-byte reading
command. Then the temperature resolution will be 1.00 C instead.
These two registers, are write/read registers, and also called set-point registers. They are
used to store the user-defined temperature limits, called overtemperature shutdown
threshold (T
At the end of each conversion the Temp data will be compared with the data stored in
these two registers in order to set the state of the device OS output; see
Each of the set-point registers contains two 8-bit data bytes consisting of one MSByte and
one LSByte the same as register Temp. However, only 9 bits of the two bytes are used to
store the set-point data in 2’s complement format with the resolution of 0.5 C.
and
Notice that because only 9-bit data are used in the set-point registers, the device uses
only the 9 MSB of the Temp data for data comparison.
Table 10.
Table 11.
When a set-point register is read, all 16 bits are provided to the bus and must be collected
by the controller to complete the bus operation. However, only the 9 most significant bits
should be used and the 7 LSB of the LSByte are equal to zero and should be ignored.
Table 12
11-bit binary
(2’s complement)
111 0011 1000
110 0100 1001
110 0100 1000
MSByte
MSByte
D8
D8
7
7
Table 11
D7
D7
6
6
shows examples of the limit data and value.
Temp register value
Tos register
Thyst register
th(ots)
D6
D6
5
5
show the bit arrangement of the Tos data and Thyst data in the data bytes.
) and hysteresis temperature (T
D5
D5
4
4
Rev. 02 — 9 December 2008
Hexadecimal value
738
649
648
D4
D4
3
3
D3
D3
2
2
…continued
D2
D2
1
1
Digital temperature sensor and thermal watchdog
D1
D1
0
0
Decimal value
LSByte
LSByte
D0
D0
200
439
440
7
7
hys
), for the device watchdog operation.
X
X
6
6
X
X
5
5
X
X
4
4
Value
25.000 C
54.875 C
55.000 C
X
X
3
3
© NXP B.V. 2008. All rights reserved.
Section
LM75B
X
X
2
2
Table 10
X
X
1
1
7.1.
9 of 29
X
X
0
0