EVALUATION KIT AVAILABLE MAX6650/MAX6651 Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface General Description Features Closed/Open-Loop Fan-Speed Control for The MAX6650/MAX6651 fan controllers use an 2 5V/12V Fans SMBus/I C-compatible interface to regulate and moni- 2 tor the speed of 5VDC/12VDC brushless fans with built- 2-Wire SMBus/I C-Compatible Interface in tachometers. They automatically force the fans Monitors Tachometer Output tachometer frequency (fan speed) to match a prepro- Single Tachometer (MAX6650) grammed value in the Fan-Speed Register by using an Up to Four Tachometers (MAX6651) external MOSFET or bipolar transistor to linearly regu- Programmable Alert Output late the voltage across the fan. The MAX6650 regulates GPIOs the speed of a single fan by monitoring its tachometer output. The MAX6651 also regulates the speed of a sin- Hardware Full-On Override gle fan, but it contains additional tachometer inputs to Synchronize Multiple Fans monitor up to four fans and control them as a single unit Four Selectable Slave Addresses when they are used in parallel. 3V to 5.5V Supply Voltage The MAX6650/MAX6651 provide general-purpose Small Packages input/output (GPIO) pins that serve as digital inputs, 10-Pin MAX (MAX6650) digital outputs, or various hardware interfaces. Capable 16-Pin QSOP (MAX6651) of sinking 10mA, these open-drain inputs/outputs can drive an LED. To add additional hardware control, con- figure GPIO1 to fully turn on the fan in case of software Ordering Information failure. To generate an interrupt when a fault condition is detected, configure GPIO0 to behave as an active- PART TEMP RANGE PIN-PACKAGE low alert output. Synchronize multiple devices by set- MAX6650EUB -40C to +85C 10 MAX ting GPIO2 (MAX6651 only) as an internal clock output MAX6650EUB+ -40C to +85C 10 MAX or an external clock input. MAX6651EEE -40C to +85C 16 QSOP The MAX6650 is available in a space-saving 10-pin MAX6651EEE+ -40C to +85C 16 QSOP MAX package, and the MAX6651 is available in a +Denotes a lead(Pb)-free/RoHS-compliant package. small 16-pin QSOP package. Applications Pin Configurations appear at end of data sheet. RAID Desktop Computers MAX is a registered trademark of Maxim Integrated Products, Inc. Servers Networking Workstations Telecommunications Typical Operating Circuit V FAN 5V OR 12V V V CC CC 3V TO 5.5V 10k MAX6650 TACH0 SCL FAN 2 SMBus/I C INTERFACE SDA FB LED ALERT C COMP GPIO0 OUT 10F FULL ON GPIO1 ADD GND For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrateds website at www.maximintegrated.com. 19-1784 Rev 5 12/12MAX6650/MAX6651 Fan-Speed Regulators and Monitors 2 with SMBus/I C-Compatible Interface ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Operating Temperature Range ...........................-40C to +85C CC FB, TACH ..........................................................-0.3V to +13.2V Junction Temperature .....................................................+150C All Other Pins..............................................-0.3V to (V + 0.3V) Storage Temperature Range .............................-65C to +150C CC Output Voltages..........................................-0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) .................................+300C CC Maximum Current Soldering Temperature (reflow) Into V , GND, V ...................................................100mA Lead(Pb)-free..............................................................+260C CC OUT Into All Other Pins ..........................................................50mA Containing lead(Pb)....................................................+240C Continuous Power Dissipation (T = +70C) A MAX (derate 5.6mW/C above +70C) .....................444mW QSOP (derate 8.3mW/C above +70C).....................667mW Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 3.0V to 5.5V, T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C and V = 5V.) CC A A CC PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLY (V ) CC Supply Voltage V 3.0 5.5 V CC Supply Current I Full-on mode, I = 0 10 mA CC OUT OUTPUT (OUT) Output Voltage Range V I = 100A 0.3 V - 0.3 V OUT OUT CC Output Sink Current I V = 0.5V 10 mA SINK OUT Output Source Current I V = V - 1.8V 50 mA SOURCE OUT CC TACHOMETER INPUTS (TACH ) 5V fan, 0 < V < 4.5V V + 0.5 V +1.5 FB FB FB Tachometer Threshold V V TACH 12V fan, 0 < V < 9V V + 1.0 V +3 FB FB FB Tachometer Input Impedance R 0 < V < 9V 70 100 150 k TACH TACH FEEDBACK (FB) DAC Differential Nonlinearity Guaranteed monotonicity on FB (Note 1) 5 LSB Useful DAC Resolution Measured at FB (Note 1) 8 bits Feedback Input Impedance R 0 < VFB < 9V 70 100 150 k FB GENERAL-PURPOSE INPUTS/OUTPUTS (GPIO ) (Note 2) Input Low Voltage V 0.8 IL(GPIO ) V V 3.6V 2 CC Input High Voltage V V IH(GPIO ) V > 3.6V 3 CC Input Hysteresis V 200 mV HYS Pullup Resistor R 100 k GPIO Output Sink Current I V = 0.4V 10 mA GPIO GPIO 2 Maxim Integrated