MAX6640AEE Maxim Integrated Products, MAX6640AEE Datasheet
MAX6640AEE
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MAX6640AEE Summary of contents
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... Fan-Speed Measurement Accuracy ♦ Temperature Monitoring Begins at POR for Fail- Safe System Protection ♦ OT and THERM Outputs for Throttling or Shutdown ♦ Measures Temperatures Up to +150°C ♦ Tiny 5mm x 5mm 16-Pin TQFN and QSOP Packages PART MAX6640AEE MAX6640ATE 16 SCL 15 SDA PWM2 1 14 ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V CC PWM1, PWM2, TACH1, and TACH2 to GND ......-0.3V to +13.5V DXP1 and DXP2 to GND ..........................-0.3V to +(V DXN to GND ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller ELECTRICAL CHARACTERISTICS (continued +3.0V to +3.6V 0°C to +125°C, unless otherwise noted. Typical values are PARAMETER SYMBOL DIGITAL INPUTS AND OUTPUTS Output Low ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller (V = 3.3V +25° STANDBY SUPPLY CURRENT vs. SUPPLY VOLTAGE 3.0 3.5 4.0 4.5 5.0 SUPPLY ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller (V = 3.3V +25° PWMOUT FREQUENCY vs. DIE TEMPERATURE -40 - TEMPERATURE (°C) PIN NAME TQFN QSOP Open-Drain Output ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Block Diagram V CC MAX6640 DXP1 PWM TEMPERATURE GENERATOR DXN PROCESSING BLOCK BLOCK DXP2 SMBus INTERFACE AND SDA REGISTERS SCL GND Write Byte Format S ADDRESS WR 7 bits Slave Address: ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller HIGH LOW SCL SDA SU:STA HD:STA SU:DAT A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 1. Temperature Data Byte Format TEMP (°C) TEMP (°C) 241 +241 240 +240 126 +126 25 +25 1.50 1 0.00 0 updated, thereby preventing reading the temperature register data from ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller the FANFAIL status bits and the output. The MAX6640 measures the fan speed again after 2s. The MAX6640 asserts FANFAIL if it detects the fan fault again. In RPM mode (either ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller TACH T T MIN-5 MIN 0xFFh TACH MAX TACH A+1 TACH MIN Figure 4. Tachometer Target Calculation bit 0 is equal to zero, the fan will be completely ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 3. Register Map REGISTER READ/ POR NO. FUNCTION WRITE STATE ADDRESS 0000 Temperature R 00h 0000 channel 1 0000 Temperature R 01h 0000 channel 2 0000 R 02h Status byte ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 3. Register Map (continued) REGISTER READ/ POR NO. FUNCTION WRITE STATE ADDRESS Fan 1 0000 R/W 12h configuration 0000 2b Fan 1 0100 R/W 13h configuration 0001 3 Fan 2 ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 3. Register Map (continued) REGISTER READ/ POR NO. FUNCTION WRITE STATE ADDRESS 0011 Fan 1 target W 26h 1100 duty cycle 0000 Fan 2 current R 27h 0000 duty cycle ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 4. Fan Duty-Cycle Rate-of-Change REGISTER 10h NOMINAL RATE OR 14h D[6:4] OF CHANGE (s) 000 0 001 0.0625 010 0.125 011 0.25 100 0.5 101 1 110 2 111 4 ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 7. Temperature Step Size FAN CONTROL TEMPERATURE D[3:2] STEP SIZE (° Fan 1 and 2 Configuration 2b (12h and 16h) The following registers select the tachometer ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 9. Tachometer Pulses per Revolution TACHOMETER PULSES PER D[7:6] REVOLUTION Applications Information Fan-Drive Circuits A variety of fan-drive circuit configurations can be used with the MAX6640 ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller V CC 4.7kΩ PWM1 3V TO 5.5V 4.7kΩ TACH1 TACH OUTPUT Figure 8. High-Side PWM Drive with “Keep-Alive” Supply V CC 100kΩ 3.3V 4.7kΩ 100kΩ PWM1 2.2μ 4.7kΩ ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller Table 10. Summary of Fan-Drive Options FIGURE DESCRIPTION 6 High-side PWM drive 7 Low-side PWM drive 8 High-side PWM drive with keep-alive supply 9 High-side linear supply 10 4-wire fan with ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller The transistor must be a small-signal type with a rela- tively high forward voltage; otherwise, the ADC input voltage range can be violated. The forward voltage at the highest expected temperature ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller CPU GPU TO CLOCK THROTTLE 20 ______________________________________________________________________________________ 5V 3.0V TO 3.6V V TACH1 CC DXP1 DXN PWM1 DXP2 PWM2 MAX6640 SDA TO SMBus MASTER SCL TACH2 3.3V TO 5.5V ALERT OT ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information 21 ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information (continued) ...
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Temperature Monitor with Dual Automatic PWM Fan-Speed Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information (continued) 23 ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 24 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products REVISION DESCRIPTION is a registered trademark of Maxim Integrated Products, Inc ...