MAX6641 19-3304 Rev 1 4/06 SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller General Description Features The MAX6641 temperature sensor and fan controller Tiny 3mm x 5mm MAX Package accurately measures the temperature of its own die and Thermal Diode Input the temperature of a remote pn junction. The device reports temperature values in digital form using a 2-wire Local Temperature Sensor serial interface. The remote pn junction is typically the Open-Drain PWM Output for Fan Drive emitter-base junction of a common-collector pnp on a CPU, FPGA, or ASIC. Programmable Fan Control Characteristics The 2-wire serial interface accepts standard System Automatic Fan Spin-Up Ensures Fan Start TM Management Bus (SMBus) write byte, read byte, send byte, and receive byte commands to read the 1C Remote Temperature Accuracy (+60C to temperature data and program the alarm thresholds. +145C) The temperature data controls a PWM output signal to Controlled Rate of Change Ensures Unobtrusive adjust the speed of a cooling fan, thereby minimizing Fan-Speed Adjustments noise when the system is running cool, but providing maximum cooling when power dissipation increases. Temperature Monitoring Begins at Power-On for The device also features an over-temperature alarm Fail-Safe System Protection output to generate interrupts, throttle signals, or shut OT Output for Throttling or Shutdown down signals. The MAX6641 operates from supply volt- ages in the 3.0V to 5.5V range and typically consumes 500A of supply current. The MAX6641 is available in a slim 10-pin MAX pack- Ordering Information age and is available over the -40C to +125C automo- tive temperature range. PIN- SMBus PKG PART PACKAGE ADDRESS CODE Applications MAX6641AUB90 10 MAX 1001 000x U10-2 Desktop Computers MAX6641AUB92 10 MAX 1001 001x U10-2 Notebook Computers MAX6641AUB94 10 MAX 1001 010x U10-2 MAX6641AUB96 10 MAX 1001 011x U10-2 Workstations Note: All devices are specified over the -40C to +125C tem- Servers perature range. Networking Equipment Industrial Pin Configuration TOP VIEW Typical Application Circuit appears at end of data sheet. I.C. 1 10 PWMOUT DXN 2 9 V CC MAX6641 DXP 3 8 SMBDATA GND 4 7 SMBCLK OT 5 6 I.C. MAX MAX is a registered trademark of Maxim Integrated Products, Inc. SMBus is a trademark of Intel Corp. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) Continuous Power Dissipation (T = +70C) A V , OT, SMBDATA, SMBCLK, PWMOUT...............-0.3V to +6V 10-Pin MAX (derate 5.6mW/C above +70C) .......... 444mW CC DXP.........................................................-0.3V to (V + 0.3V) Operating Temperature Range .........................-40C to +125C CC DXN ......................................................................-0.3V to +0.8V Junction Temperature......................................................+150C ESD Protection Storage Temperature Range ............................-65C to +150C (all pins, Human Body Model) .......2000V Lead Temperature (soldering, 10s) ............................... +300C Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = +3.0V to +5.5V, T = 0C to +125C, unless otherwise noted. Typical values are at V = 3.3V, T = +25C.) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Supply Voltage Range V 3.0 5.5 V CC Operating Current SMBDATA, SMBCLK not switching 0.5 1 mA +25C T +125C, R 1 T = +60C A 0C T +145C, R External Temperature Error V = 3.3V 3 C CC +25C T = +100C A 0C T +145C, R 4 0C T +125C A +25C T +100C -3 +3 A Internal Temperature Error V = 3.3V C CC 0C T +125C -4 +4 A 1C Temperature Resolution 8 Bits Conversion Time 200 250 300 ms PWM Frequency Tolerance -20 +20 % High level 80 100 120 Remote-Diode Sourcing Current A Low level 8 10 12 DXN Source Voltage 0.7 V I/O OT, SMBDATA, PWMOUT Output V I = 6mA 0.4 V OL OUT Low Voltage OT, SMBDATA, PWMOUT I V = 5.5V 1 A OH CC Output-High Leakage Current SMBDATA, SMBCLK Logic-Low V V = 3V to 5.5V 0.8 V IL CC Input Voltage SMBDATA, SMBCLK Logic-High V V = 3V to 5.5V 2.1 V IH CC Input Voltage SMBDATA, SMBCLK Leakage 1A Current SMBDATA, SMBCLK Input C 5pF IN Capacitance 2 MAX6641