Features • Directly senses die temperature of remote ICs • Senses temperature of remote diodes • SMBus compatible interface, supports SMBus Timeout • Register readback capability • 7 bit plus sign temperature data format • 2 address select lines enable 9 LM84s to be connected to a single bus Description The LM84 is a remote diode temperature sensor, Delta-Sigma analog-to-digital converter, and digital over-temperature detector with an SMBus™ interface. The LM84 senses its own temperature as well as the temperature of a target IC with a diode junction, such as a Pentium® II processor or a diode connected 2N3904. A diode junction (semiconductor junction) is required on the target IC's die. A host can query the LM84 at any time to read the temperature of this diode as well as the temperature state of the LM84 itself. A T_CRIT_A# interrupt output becomes active when the temperature is greater than a programmable comparator limit, T_CRIT. The host can program as well as read back the state of the T_CRIT register. Three state logic inputs allow two pins (ADD0, ADD1) to select up to 9 SMBus address locations for the LM84. The sensor powers up with default thresholds of 127°C for T_CRIT. Key Specification Supply Voltage 3.0V - 3.6V Supply Current 1 mA (max) Local Temperature Accuracy ±1.0°C (typ) Remote Diode Temperature Accuracy   +60°C to +100°C ±3°C (max) 0°C to +125°C ±5°C (max) Applications • System Thermal Management • Personal Computers • Electronic Test Equipment • Office Electronics • HVAC

Also Recommended LM95213▲ Dual Remote Diode Input LM95214▲ Quad Remote Diode Input LM95233▲ Dual Channel With TruTherm Support LM95234▲ Quad Channel With TruTherm Support LM95235▲ Smaller Package With TruTherm Support MY BRIEFCASE                                       Click any "Briefcase" icon to add an item

Datasheet

Title		Size	Date	Other Language
	LM84 Diode Input Digital Temperature Sensor with Two-Wire Interface	168 Kbytes	2-Mar-01	日本語

Featured Application Notes

Title		Size	Date	Other Language
	AN-1155: Application Note 1155 A Simple Software I2C Routine for the COP8	82 Kbytes	15-May-04

More Application Notes

Title		Size	Date	Other Language
	AN-1260: Application Note 1260 Autonomous Fan Control for Processor Systems Using the LM85	74 Kbytes	10-Mar-04
	AN-1262: Application Note 1262 Four-Speed Fan Control Using Simple Remote Diode Temperature Sensor	70 Kbytes	1-Oct-02

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Standard Pack Size
LM84BIMQA/NOPB LM84BIMQA RoHS	SSOP	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 1776 AVNET-EM Worldwide 255 DIGIKEY Worldwide 185 FARNELL Europe and Asia 205 FUTURE Worldwide 490 TAYLOR Americas 360	$1.61 each at 1K+ pcs	rail of 95
LM84BIMQAX/NOPB LM84BIMQAX RoHS	SSOP	Full production Lead Time: 8 weeks	Distributor Region Qty DIGIKEY Worldwide 0 FUTURE Worldwide 1100	$1.61 each at 1K+ pcs	reel of 2500

Obsolete Versions

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM84CIMQA	NONE	NONE	04 Mar 2003
LM84CIMQAX	NONE	NONE	04 Mar 2003

Design Tools

Title	Size	Date
LMxx - Windows 95/98 VXD drivers with stand alone application for talking to temperature sensors or hardware monitors on a mother board	1366 Kbytes	28-Jul-2003

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM84BIMQA	CS065	2	38968	52	0	4402000	1	1249079519
LM84BIMQAX	CS065	2	38968	52	0	4402000	1	1249079519

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.

Obsolete Versions

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM84CIMQA	NONE	NONE	04 Mar 2003
LM84CIMQAX	NONE	NONE	04 Mar 2003