MAX6641AUB92+ Maxim Integrated Products, MAX6641AUB92+ Datasheet
MAX6641AUB92+
Specifications of MAX6641AUB92+
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MAX6641AUB92+ Summary of contents
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... Servers Networking Equipment Industrial Typical Application Circuit appears at end of data sheet. µMAX is a registered trademark of Maxim Integrated Products, Inc. SMBus is a trademark of Intel Corp. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) OT, SMBDATA, SMBCLK, PWMOUT...............-0. DXP .........................................................…-0. DXN ......................................................................-0.3V to +0.8V ESD Protection (all pins, Human Body Model) ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller ELECTRICAL CHARACTERISTICS (continued +3.0V to +5.5V +125 C, unless otherwise noted. Typical values are PARAMETER SYMBOL SMBus-COMPATIBLE TIMING (Note 1) (See ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller (V = 3.3V +25 C, unless otherwise noted REMOTE TEMPERATURE ERROR vs. POWER-SUPPLY NOISE FREQUENCY +80 C, 250mV SQUARE WAVE APPLIED ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller PIN NAME 1, 6 I.C. Internally Connected. Must be connected to GND. Combined Remote-Diode Cathode Connection and A/D Negative Input. Connect the cathode of the 2 DXN remote-diode-connected transistor to DXN. Combined ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Table 1. Register Functions READ/ REGISTER POR FUNCTION/ WRITE ADDRESS STATE NAME Read remote (external) R 00h 0000 0000 temperature Read local R 01h 0000 0000 (internal) temperature Configuration R/W 02h 0000 ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Table 1. Register Functions (continued) READ/ REGISTER POR FUNCTION/ WRITE ADDRESS STATE NAME Local-diode R/W 0Ch 0000 0000 fan-start temperature R/W 0Dh 0000 xxxx configuration Duty-cycle R/W 0Eh 101x xxxx rate of ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Write Byte Format S ADDRESS WR 7 bits Slave address: equiva- lent to chip-select line of a 3-wire interface Read Byte Format S ADDRESS WR ACK 7 bits Slave address: equivalent to ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller LOW HIGH SMBCLK SMBDATA t t HD:STA SU:STA A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Table 2. Configuration Byte Definition (02h) BIT NAME 7 — 6 — 5 TIMEOUT 4 FAN PWM INVERT 3 MIN DUTY CYCLE 2 SPIN-UP DISABLE 1 — 0 — Set bit D7 ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Fan Instantaneous Duty Cycle (0Ah) Read the fan instantaneous duty-cycle register to deter- mine the duty cycle at PWMOUT at any time. The POR state of the fan instantaneous duty-cycle register is ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller Table 5. PWM Frequency Select (10h) PWM FREQUENCY SELECT A SELECT B (Hz 100 X 35k frequency setting is used for controlling fans that have ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller The frequency-select register controls the frequency of the PWM signal. When the PWM signal modulates the power supply of the fan, a low PWM frequency (usually 33Hz) should be used to ensure ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller The duty cycle is limited to the value in the fan maxi- mum duty-cycle register. If the duty-cycle value is larg- er than the maximum fan duty cycle, it can be set ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller The effects of the ideality factor and series resistance are additive. If the diode has an ideality factor of 1.002 and series resistance the total offset can be cal- ...
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SMBus-Compatible Temperature Monitor with Automatic PWM Fan-Speed Controller GND 10 mils DXP 10 mils DXN GND Figure 9. Recommended DXP-DXN PC Traces Twisted-Pair and Shielded Cables Use a twisted-pair cable to connect the remote sensor for remote-sensor distance longer than ...
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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 © 2006 Maxim Integrated Products ...