LM75BDP NXP Semiconductors, LM75BDP Datasheet - Page 4

• 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
7. Functional description
LM75B_2
Product data sheet
6.2 Pin description
7.1 General operation
Table 2.
The LM75B uses the on-chip band gap sensor to measure the device temperature with
the resolution of 0.125 C and stores the 11-bit 2's complement digital data, resulted from
11-bit A-to-D conversion, into the device Temp register. This Temp register can be read at
any time by a controller on the I
conversion in progress during the read operation.
The device can be set to operate in either mode: normal or shutdown. In normal operation
mode, the temp-to-digital conversion is executed every 100 ms and the Temp register is
updated at the end of each conversion. During each ‘conversion period’ (T
100 ms the device takes only about 10 ms, called ‘temperature conversion time’ (t
to complete a temperature-to-data conversion and then becomes idle for the time
remaining in the period. This feature is implemented to significantly reduce the device
power dissipation. In shutdown mode, the device becomes idle, data conversion is
disabled and the Temp register holds the latest result; however, the device I
interface is still active and register write/read operation can be performed. The device
operation mode is controllable by programming bit B0 of the configuration register. The
temperature conversion is initiated when the device is powered-up or put back into normal
mode from shutdown.
In addition, at the end of each conversion in normal mode, the temperature data (or Temp)
in the Temp register is automatically compared with the overtemperature shutdown
threshold data (or T
stored in the Thyst register, in order to set the state of the device OS output accordingly.
The device Tos and Thyst registers are write/read capable, and both operate with 9-bit
2's complement digital data. To match with this 9-bit operation, the Temp register uses
only the 9 MSB bits of its 11-bit data for the comparison.
The way that the OS output responds to the comparison operation depends upon the OS
operation mode selected by configuration bit B1, and the user-defined fault queue defined
by configuration bits B3 and B4.
Symbol
SDA
SCL
OS
GND
A2
A1
A0
V
CC
Pin description
Pin
1
2
3
4
5
6
7
8
th(ots)
Rev. 02 — 9 December 2008
) stored in the Tos register, and the hysteresis data (or T
Description
Digital I/O. I
Digital input. I
Overtemp Shutdown output; open-drain.
Ground. To be connected to the system ground.
Digital input. User-defined address bit 2.
Digital input. User-defined address bit 1.
Digital input. User-defined address bit 0.
Power supply.
2
C-bus. Reading temperature data does not affect the
Digital temperature sensor and thermal watchdog
2
C-bus serial bidirectional data line; open-drain.
2
C-bus serial clock input.
© NXP B.V. 2008. All rights reserved.
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