• 简体中文
• English

LM75B: Digital temperature sensor and thermal watchdog

The LM75B is a temperature-to-digital converter using an on-chip band gap temperature sensor and Sigma-Delta A-to-D conversion technique with an overtemperature detection output. The LM75B contains a number of data registers: Configuration register (Conf) to store the device settings such as device operation mode, OS operation mode, OS polarity and OS fault queue; temperature register (Temp) to store the digital temp reading, and set-point registers (Tos and Thyst) to store programmable overtemperature shutdown and hysteresis limits, that can be communicated by a controller via the 2-wire serial I²C-bus interface. The device also includes an open-drain output (OS) which becomes active when the temperature exceeds the programmed limits. There are three selectable logic address pins so that eight devices can be connected on the same bus without address conflict.

The LM75B can be configured for different operation conditions. It can be set in normal mode to periodically monitor the ambient temperature, or in shutdown mode to minimize power consumption. The OS output operates in either of two selectable modes: OS comparator mode or OS interrupt mode. Its active state can be selected as either HIGH or LOW. The fault queue that defines the number of consecutive faults in order to activate the OS output is programmable as well as the set-point limits.

The temperature register always stores an 11-bit two’s complement data giving a temperature resolution of 0.125 °C. This high temperature resolution is particularly useful in applications of measuring precisely the thermal drift or runaway. When the LM75B is accessed the conversion in process is not interrupted (that is, the I²C-bus section is totally independent of the Sigma-Delta converter section) and accessing the LM75B continuously without waiting at least one conversion time between communications will not prevent the device from updating the Temp register with a new conversion result. The new conversion result will be available immediately after the Temp register is updated.

The LM75B powers up in the normal operation mode with the OS in comparator mode, temperature threshold of 80 °C and hysteresis of 75 °C, so that it can be used as a stand-alone thermostat with those pre-defined temperature set points.

LM75B: Product Block Diagram

sot1069-2_3d

Data Sheets (1)

Application Notes (3)

Users Guides (3)

Brochures (2)

Package Information (4)

Packing (4)

Supporting Information (4)

IBIS Model

• LM75B IBIS model (REV 1.0) ibs LM75B_3_3V 9/16/2014
• LM75BDP IBIS model (REV 1.0) ibs LM75BDP 9/19/2012

Ordering Information

Package Information

Product ID	Package Description	Outline Version	Reflow/Wave Soldering	Packing	Product Status	Part NumberOrdering code(12NC)	Marking	Chemical Content	RoHS / Pb Free / RHF	LeadFree Conversion Date	EFR	IFR(FIT)	MTBF(hour)	MSL	MSL LF
LM75BDP		SOT505-1	Reflow_Soldering_Profile	Reel 13" Q1/T1	Active	LM75BDP,118 (9352 858 36118)	LM75B	LM75BDP		Always Pb-free	0.0	2.0	5E8	1	1
LM75BDP/DG		SOT505-1	Reflow_Soldering_Profile	Reel 13" Q1/T1	Active	LM75BDP/DG,118 (9352 933 85118)	LM75B	LM75BDP/DG		Always Pb-free	0.0	2.0	5E8	1	1
LM75BD		SOT96-1	SO-SOJ-REFLOW SO-SOJ-WAVE SO-SOJ-REFLOW SO-SOJ-WAVE	Reel 13" Q1/T1	Active	LM75BD,118 (9352 858 37118)	LM75BD	LM75BD		Always Pb-free	0.0	2.0	5E8	1	1
				Bulk Pack	Active	LM75BD,112 (9352 858 37112)	LM75BD	LM75BD		Always Pb-free	0.0	2.0	5E8	1	1
LM75BGD		SOT996-2		Reel 7" Q3/T4, Reverse	Active	LM75BGD,125 (9352 882 39125)	75B	LM75BGD		Always Pb-free	0.0	2.0	5E8	1	1
LM75BTP		SOT1069-2		Reel 7" Q2/T3	Active	LM75BTP,147 (9352 965 01147)	M75	LM75BTP		Always Pb-free	0.0	2.0	5E8	1	1