Features • 8-bit [Sigma][Delta] ADC • Monitors 16 power supplies • Monitors 2 remote thermal diodes • Internal ambient temperature sensing • Programmable autonomous fan control based on temperature readings with fan boost support • Fan control based on 13-step lookup table • Temperature reading digital filter • 1.0°C digital temperature sensor resolution • 0.5°C temperature resolution for fan control • 2 PWM fan speed control outputs • 4 fan tachometer inputs • Dual processor thermal throttling (PROCHOT#) monitoring • Dual dynamic VID monitoring (6 VIDs per processor) • 8 general purpose I/Os: • 4 can be configured as fan tachometer inputs • 2 can be configured to connect to THERMTRIP# from a processor • 2 are standard GPIOs that could be used to monitor IERR# signal • 2 general purpose inputs that can be used to monitor SCSI termination signals • Limit register comparisons of all monitored values • 2-wire, SMBus 2.0 compliant, serial digital interface • Supports byte/block read and write • Configurable slave address (tri-level pin selects 1 of 3 possible addresses) • 2.5V reference voltage output • 56-pin TSSOP package • XOR-tree test mode Description The LM93, hardware monitor, has a two wire digital interface compatible with SMBus 2.0. Using an 8-bit [Sigma][Delta] ADC, the LM93 measures the temperature of two remote diode connected transistors as well as its own die and 16 power supply voltages. To set fan speed, the LM93 has two PWM outputs that are each controlled by up to four temperature zones. The fan-control algorithm is lookup table based. The LM93 includes a digital filter that can be invoked to smooth temperature readings for better control of fan speed. The LM93 has four tachometer inputs to measure fan speed. Limit and status registers for all measured values are included. The LM93 builds upon the functionality of previous motherboard management ASICs and uses some of the LM85's features (i.e. smart tachometer mode). It also adds measurement and control support for dynamic Vccp monitoring and PROCHOT#. It is designed to monitor a dual processor Xeon class motherboard with a minimum of external components. Key Specification Voltage Measurement Accuracy ±2% FS (max) Resolution 8-bits, 1°C Temperature Sensor Accuracy ±3°C (max) Temperature Range:   LM93 Operational 0°C to +85°C Remote Temp Accuracy 0°C to +125°C Power Supply Voltage +3.0V to +3.6V Power Supply Current 0.9 mA Applications • Servers • Workstations • Multi-Microprocessor based equipment

Also Recommended LM94▲ PI Fan Control And TruTherm(TM) Remote Diode Technology MY BRIEFCASE                                       Click any "Briefcase" icon to add an item

Typical Application *click for larger image	Block Diagram click for larger image
Typical Performance *click for larger image

Datasheet

Title		Size	Date	Other Language
	LM93 Hardware Monitor with Integrated Fan Control for Server Management	654 Kbytes	14-Apr-04

Featured Application Notes

Title		Size	Date	Other Language
	AN-1262: Application Note 1262 Four-Speed Fan Control Using Simple Remote Diode Temperature Sensor	70 Kbytes	1-Oct-02

More 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
	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

Design Tools

Title	Size	Date
SensorEval Software for Thermal Mangement Products

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM93CIMT	CMOS7	0	18406	0	0	1089000	4	309006723
LM93CIMTX	CMOS7	0	18406	0	0	1089000	4	309006723

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.

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