MAX6650EUB-T Maxim Integrated Products, MAX6650EUB-T Datasheet
MAX6650EUB-T
Specifications of MAX6650EUB-T
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MAX6650EUB-T Summary of contents
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... Supply Voltage ♦ Small Packages 10-Pin µMAX (MAX6650) 16-Pin QSOP (MAX6651) PART MAX6650EUB MAX6650EUB+ MAX6651EEE MAX6651EEE+ + Denotes a lead(Pb)-free/RoHS-compliant package. SMBus is a trademark of Intel Corp. µMAX is a registered trademark of Maxim Integrated Products, Inc. Pin Configurations appear at end of data sheet. ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V CC FB, TACH_ ..........................................................-0.3V to +13.2V All Other Pins..............................................-0. Output Voltages..........................................-0. Maximum Current Into V , GND, V ...
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Fan-Speed Regulators and Monitors with SMBus/I ELECTRICAL CHARACTERISTICS (continued 3.0V to 5.5V -40°C to +85°C, unless otherwise noted. Typical values are PARAMETER SYMBOL ADDRESS SELECT (ADD) ADD Input Low Voltage V IL(ADD) ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface TIMING CHARACTERISTICS (continued 3.0V to 5.5V -40°C to +85°C, unless otherwise noted. Typical values are PARAMETER SYMBOL Setup Time for Stop Condition t ...
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Fan-Speed Regulators and Monitors with SMBus/I PIN PIN NAME MAX6650 MAX6651 1 1 TACH0 TACH2, TACH3, — TACH1 2 4 GND 3 5 SDA 4 6 SCL 5 8 ADD — GPIO4, GPIO3 6 9 ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface SMBus 5.5V INTERFACE FAN SPEED SCL CONFIGURE SMBus SDA INTERFACE ALARM ENABLE ALARM STATUS TACH COUNT COUNT TIME GPIO DEF GPIO ...
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Fan-Speed Regulators and Monitors with SMBus ADDRESS 7 bits 0 Slave Address Figure 2a. SMBus Protocol: Write Byte Format WR S ADDRESS 7 bits 0 Slave Address S ADDRESS RD 7 bits 1 Slave Address. Repeated due to ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface 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 ...
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Fan-Speed Regulators and Monitors with SMBus/I Table 2. Command-Byte Assignments REGISTER COMMAND SPEED 0000 0000 CONFIG 0000 0010 GPIO DEF 0000 0100 DAC 0000 0110 ALARM ENABLE 0000 1000 ALARM 0000 1010 TACH0 0000 1100 TACH1 0000 1110 TACH2 0001 ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface Table 4. Configuration Byte Register BIT NAME 7 (MSB — MODE 5/12V (LSB) SCALE V CC MAX6650 MAX6651 100kΩ GPIO GPIO_ STATUS ...
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Fan-Speed Regulators and Monitors with SMBus/I Table 5. GPIO Definition Register POR MAX6650 BIT (DEFAULT) PIN STATE N (must (must be 1) N/A 5:4 11 (must be 11) 3:2 11 GPIO1 1:0 11 ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface Table 7. Alarm-Enable Register Bit Masks BIT NAME 7 (MSB — 4 GPIO2 (MAX6651 only) 3 GPIO1 2 TACH 1 MIN 0 (LSB) MAX 1 = Enabled Table 8. ...
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Fan-Speed Regulators and Monitors with SMBus 5.5V 2 SMBus/I C INTERFACE Figure 6. Fan Control with a Bipolar Transistor tion, use DAC values between 08h and B0h (see Typical Operating Characteristics ). When using the closed-loop ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface impedance of the tachometer input (150kΩ max) or the feedback input (150kΩ max). Compensation Capacitor A compensation capacitor is needed from the fan’s low side to ground to stabilize the analog ...
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Fan-Speed Regulators and Monitors with SMBus 5.5V MAX6651 Figure 8. Monitoring Multiple Fans very rough rule of thumb, 12V fans can be expected to experience problems somewhere around 1/4 to 1/2 their rated speed. Predicting Future ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface TO INT PIN ON NC Figure Application downtime. The system should be designed so that the number of fans used is one more than are actually needed. ...
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Fan-Speed Regulators and Monitors with SMBus μC SCL SDA GND Figure 10. Temperature Monitoring and Fan Control ______________________________________________________________________________________ 2 C-Compatible Interface GND ADD1 MAX1617A ADD0 DXP STBY V DXN CC SCL SDA ALERT ALERT GPIO0 FULL ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface 5.5V 2 SMBus/I C INTERFACE MAX6501 TOVER Figure 11. MAX6501 Hardware Fail-Safe MAX6501 TOVER MAX6501 TOVER MAX6501 TOVER Figure 12. MAX6501 Hardware Fail-Safe independently control each fan. ...
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Fan-Speed Regulators and Monitors with SMBus 5.5V 2 SMBus/I C INTERFACE Figure 13. Hot-Swap Application For parallel fan control while monitoring only a single fan, select the MAX6650. Synchronized Fan Control (MAX6651 Only) In systems with ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface ware control. To enter full-on mode through hardware, see the Setting Up the GPIOs section. Note that a hard- ware full-on overrides all other modes. Configure the MAX6650/MAX6651 to run in ...
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Fan-Speed Regulators and Monitors with SMBus/I The MAX6650 regulates fan speed in the following manner. The output of an internal 254kHz oscillator is divided by 128, generating a roughly 2kHz signal. This signal is divided by 1 plus the value ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface We will start with (to increase stability SCALE could be tried improve response time could be tried). Second, calculate the appropriate value ...
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Fan-Speed Regulators and Monitors with SMBus/I Synchronizing Fans GPIO2 can be configured to allow multiple MAX6651s to synchronize the speeds of the fans they are driving (Figure 14). Synchronization is accomplished by having one of the MAX6651s (or an external ...
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Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface TOP VIEW TACH0 1 GND 2 SDA 3 SCL 4 ADD 5 For the latest package outline information and land patterns www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” ...
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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 ____________________ 25 © 2010 Maxim Integrated Products ...