MAX6643LBBAEE+T Maxim Integrated Products, MAX6643LBBAEE+T Datasheet
MAX6643LBBAEE+T
Specifications of MAX6643LBBAEE+T
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MAX6643LBBAEE+T Summary of contents
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... Workstations Pin Configurations, Typical Operating Circuit, and Selector Guide appear at end of data sheet. µMAX is a registered trademark of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V DD PWM_OUT, OT, and FANFAIL to GND.....................-0.3V to +6V FAN_IN1 and FAN_IN2 to GND...........................-0.3V to +13.2V DXP_ to GND.........................................................-0.3V to +0.8V FULLSPD, FULLSPD, TH_, ...
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Automatic PWM Fan-Speed Controllers with ELECTRICAL CHARACTERISTICS (continued +3.0V to +5.5V - +125 C, unless otherwise noted. Typical values are PARAMETER SYMBOL DIGITAL INPUTS (FULLSPD, FULLSPD, TACHSET) Logic-Input High Logic-Input ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output PIN MAX6643 MAX6644 MAX6645 — — — — — 10, 11 10, 11 ...
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Automatic PWM Fan-Speed Controllers with PIN MAX6643 MAX6644 MAX6645 12 12 13 Detailed Description The MAX6643/MAX6644/MAX6645 measure temperature and automatically adjust fan speed to ensure optimum cooling while minimizing acoustic noise from the fan. The ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output Table 2. Setting T LOW (MAX6643 and MAX6644) TL2 TL1 High High-Z 0 High-Z High-Z High High High-Z = High impedance. There ...
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Automatic PWM Fan-Speed Controllers with T , the duty cycle may increase just a few percent HIGH above the minimum duty cycle. If the power dissipation or ambient temperature increases to a high-enough value, the duty cycle may eventually need ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output Table 3. Configuring the FAN_IN_ Inputs with TACHSET VDD TACHSET FAN_IN1 MAX6643 Tachometer MAX6644 Tachometer MAX6645 Tachometer Table 4. Setting the Overtemperature Thresholds (T ) (MAX6643 and MAX6644) OVERT OT2 OT1 0 0 ...
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Automatic PWM Fan-Speed Controllers with 1 TH1 4. FANFAIL FANFAIL ALARM 5 6 DXP2 7 GND 8 DXP1 Figure 3. MAX6644 Using Two External Transistors to Measure Remote Temperatures and Control Two 2-Wire Fans. The fan’s ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output 4.7k TO FANFAIL ALARM Figure 5. Using the MAX6645 to Monitor Two Fans 10 ______________________________________________________________________________________ V (+3.0V TO +5.5V 4. FANFAIL TACHSET PWM_OUT TACHOMETER 8 MODE ...
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Automatic PWM Fan-Speed Controllers with 4.7k TO FANFAIL ALARM 4.7k TO FANFAIL ALARM Figure 6. Using Two MAX6643s, Each Controlling a Separate Fan ______________________________________________________________________________________ Overtemperature Output V (+3.0V TO +5.5V TH1 TL2 TH2 ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output Effect of Series Resistance Series resistance in a sense diode contributes addition- al errors. For nominal diode currents of 10µA and 100µA, change in the measured voltage is 100 A 10 ...
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Automatic PWM Fan-Speed Controllers with 3) Route the DXP and GND traces parallel and close to each other, away from any high-voltage traces such as +12VDC. Avoid leakage currents from PCB conta- mination. A 20M leakage path from DXP to ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output TOP VIEW TH1 1 16 TL2 2 15 TL1 3 14 MAX6643 FANFAIL 4 13 TACHSET 5 12 FULLSPD 6 11 (FULLSPD) GND 7 10 DXP 8 9 QSOP () ARE FOR MAX6643_A ...
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Automatic PWM Fan-Speed Controllers with DXP1/(DXP) TEMPERATURE TEMPERATURE DXP2 SENSOR MAX6643 MAX6644 MAX6645 () ARE FOR MAX6643 ONLY. 1 TH1 2 TL2 4.7k 3 TL1 TO FANFAIL 4 FANFAIL ALARM 5 TACHSET 6 FULLSPD 7 GND 8 DXP ______________________________________________________________________________________ Overtemperature ...
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Automatic PWM Fan-Speed Controllers with Overtemperature Output (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 16 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, QSOP .150", .025" LEAD ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17 © 2007 Maxim Integrated Products ...