MAX6620ATI+ Maxim Integrated Products, MAX6620ATI+ Datasheet
MAX6620ATI+
Specifications of MAX6620ATI+
Related parts for MAX6620ATI+
MAX6620ATI+ Summary of contents
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... Acoustics ♦ Bus Interface ♦ 3.0V to 5.5V Supply Voltage Range ♦ 250µA (typ) Operating Supply Current ♦ 3µA (typ) Shutdown Supply Current ♦ Small 5mm x 5mm Footprint PART MAX6620ATI+ 2 C-compati- + Denotes a lead-free package Exposed paddle. Applications TOP VIEW TACH1 DACFB1 ...
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Quad Linear Fan-Speed Controller ABSOLUTE MAXIMUM RATINGS VCC to GND ..........................................................-0.3V to +6.0V FAN_FAIL, SDA, SCL to GND ...............................-0.3V to +6.0V ADDR, SPINUP_START, DAC_START, WD_START, X1 GND ........................................-0. All Other Pins to GND..........................................-0.3V to +13.5V Input ...
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Quad Linear Fan-Speed Controller ELECTRICAL CHARACTERISTICS (continued -40°C to +125° 3.0V to 5.5V, unless otherwise noted. Typical values are PARAMETER SYMBOL Fan Control Accuracy (Note 4) XTAL Oscillator Startup Time X1 Input ...
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Quad Linear Fan-Speed Controller ELECTRICAL CHARACTERISTICS (continued -40°C to +125° 3.0V to 5.5V, unless otherwise noted. Typical values are PARAMETER SYMBOL Maximum Receive SCL/SDA Fall Time Minimum Receive SCL/SDA Fall Time Transmit ...
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Quad Linear Fan-Speed Controller (V = 3.3V 12V +25°C, unless otherwise noted.) CC FAN A TACH COUNT ACCURACY WITH INT CLK vs. SUPPLY VOLTAGE 2 12V FAN 1.5 1.0 0 0°C A ...
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Quad Linear Fan-Speed Controller (V = 3.3V 12V +25°C, unless otherwise noted.) CC FAN A TACH COUNT ACCURACY WITH INT CLK vs. SUPPLY VOLTAGE 2 5.0V FAN 1 0° ...
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Quad Linear Fan-Speed Controller PIN NAME 2 1 SCL I C Serial-Clock Input. Can be pulled up to 5.5V regardless of V Open-Drain SDA circuit when V Startup Watchdog Set Input. This input is sampled when power is ...
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Quad Linear Fan-Speed Controller Detailed Description The MAX6620 controls the speeds four fans using four independent linear voltage outputs. The drive voltages for the fans are controlled directly over 2 the I C interface. Each of the ...
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Quad Linear Fan-Speed Controller LOW HIGH SCL SDA t t HD:STA SU:STA A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE D = R/W BIT ...
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Quad Linear Fan-Speed Controller A master initiates communication with a slave device by issuing a START condition followed by a slave address byte. As shown in Figure 5, the slave address byte con- sists of 7 address bits and a ...
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Quad Linear Fan-Speed Controller Figure 6. Read and Write Summary ______________________________________________________________________________________ 11 ...
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Quad Linear Fan-Speed Controller nominally 12V or 5V. The drive to the fans is proportion- . See the Fan_ Target Drive Voltage Registers FAN and the Applications Information sections for more details. DAC (Voltage) Mode. In DAC ...
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Quad Linear Fan-Speed Controller ter’s bit D4 can be used to cause a fan failure to force the remaining fan speeds to 100%. The MAX6620 includes an optional I 2 tion that monitors the I C bus for transactions. When ...
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Quad Linear Fan-Speed Controller 14 ______________________________________________________________________________________ Registers Register Map ...
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Quad Linear Fan-Speed Controller ______________________________________________________________________________________ Register Map (continued) 15 ...
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Quad Linear Fan-Speed Controller BIT R/W Run run 1 = standby POR normal operation 6 R reset all registers to POR values This bit automatically resets itself and will always return a ...
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Quad Linear Fan-Speed Controller Global Configuration Register (00h)—POR = 0000 0XXX (continued) BIT R Watchdog: When active, the watchdog monitors SDA and SCL for valid I transactions between the master and the MAX6620 within the watchdog period, ...
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Quad Linear Fan-Speed Controller BIT R/W Fan 4 Fault Status: Indicates which fans have had faults detected. When a fan fault is detected, the drive to the fan is disabled and the corresponding fault bit is set. The fault bits ...
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Quad Linear Fan-Speed Controller Fan_ Configuration Registers (02h, 03h, 04h, 05h)—POR = 0XX0 0000 BIT R/W RPM/DAC DAC mode. The fan drive voltage is set by the value in the Fan_ Target Drive Voltage register RPM ...
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Quad Linear Fan-Speed Controller Fan_ Dynamics Registers (06h, 07h, 08h, 09h)—POR = 0100 1100 BIT R/W Fan_ Speed Range: The MAX6620 determines fan speed by counting the number of internal 8192Hz clock cycles (using an 11- bit counter) during one ...
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Quad Linear Fan-Speed Controller Fan_ Dynamics Registers (06h, 07h, 08h, 09h)—POR = 0100 1100 (continued) BIT R/W Fan_ DAC Rate-of-Change: The fan drive voltage (at the DACFB_ inputs) varies from 0 to full scale in 512 increments. The rate-of- change ...
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Quad Linear Fan-Speed Controller Fan_ TACH Count Registers (10h, 12h, 14h, 16h)—POR = 1111 1111 BIT R Fan_ TACH Count D10:D3: 5 Indicates the number of 8192Hz clock pulses counted during the counting period. The Fan_ TACH Count ...
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Quad Linear Fan-Speed Controller Fan_ Target TACH Count Registers (20h, 22h, 24h, 26h)—POR = 0011 1100 The Fan_ Target TACH Count consists of 11 bits con- tained in two bytes. The two bytes must be written in 2 order in ...
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Quad Linear Fan-Speed Controller Fan_ Target Drive Voltage Registers (28h, 2Ah, 2Ch, 2Eh)—POR = XXXX XXXX The Fan_ Target Drive Voltage consists of 9 bits con- tained in two bytes. The two bytes must be written in 2 order in ...
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Quad Linear Fan-Speed Controller Applications Information External Pass Transistors Match external pass transistors to the fans being used. Ensure that the pass transistor is capable of handling the maximum fan current. For best results, the pass transistor’s maximum current rating ...
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Quad Linear Fan-Speed Controller FAN_FAIL MASTER V CC ADDR DAC_START SPINUP_START WD_START (OPTIONAL CRYSTAL) Figure 7. Using Low Dropout Voltage Regulators Instead of Discrete Transistors as the Pass Devices 26 ______________________________________________________________________________________ DACOUT1 DACFB1 V FAN V ...
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Quad Linear Fan-Speed Controller Initial Settings: • Begin with the POR settings. The POR value of the fan_ DAC rate-of-change bits (4:2 of the Fan_ Dynamics register) can yield slower fan speed changes than desired. If this is the case, ...
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Quad Linear Fan-Speed Controller FAN_FAIL SDA MASTER SCL ADDR V CC DAC_START SPINUP_START WD_START X1 (OPTIONAL CRYSTAL) X2 Chip Information PROCESS: CMOS 28 ______________________________________________________________________________________ DACOUT1 DACFB1 FAN TACH1 0.1μF 0.1μF DACOUT2 DACFB2 TACH2 ...
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Quad Linear Fan-Speed Controller (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.) ______________________________________________________________________________________ Package Information 29 ...
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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. 30 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2008 Maxim Integrated Products Package Information (continued registered trademark of Maxim Integrated Products, Inc ...