MAX6615/MAX6616 19-3713 Rev 2 10/08 Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs General Description Features The MAX6615/MAX6616 monitor two temperature chan- Two Thermistor Inputs nels, either the internal die temperature and the temper- Two Open-Drain PWM Outputs for Fan-Speed ature of an external thermistor, or the temperatures of Control two external thermistors. The temperature data controls a PWM output signal to adjust the speed of a cooling Local Temperature Sensor fan, thereby minimizing noise when the system is run- Six GPIOs (MAX6616) ning cool, but providing maximum cooling when power dissipation increases. The fans tachometer output sig- Programmable Fan-Control Characteristics nals are monitored by the MAX6615/MAX6616 to detect Controlled PWM Rate-of-Change Ensures fan failure. If a fan failure is detected, the FAN FAIL Unobtrusive Fan-Speed Adjustments output is asserted. The 2-wire serial interface accepts standard system Fail-Safe System Protection TM management bus (SMBus ) write byte, read byte, OT Output for Throttling or Shutdown send byte, and receive byte commands to read the Nine Different Pin-Programmable SMBus temperature data and program the alarm thresholds. The programmable alarm output can be used to gener- Addresses ate interrupts, throttle signals, or overtemperature shut- 16-Pin and 24-Pin QSOP Packages down signals. The MAX6616 features six GPIOs to provide additional flexibility. All of the GPIOs power-up as inputs, with the exception of GPIO0, which powers up as either an input Ordering Information or an output as determined by connecting the PRESET pin to ground or V . PART TEMP RANGE PIN-PACKAGE CC MAX6615AEE -40C to +125C 16 QSOP The MAX6616 is available in a 24-pin QSOP package, while the MAX6615 is available in a 16-pin QSOP pack- MAX6616AEG -40C to +125C 24 QSOP age. Both devices operate from a single-supply voltage range of 3.0V to 5.5V, have operating temperature Functional Diagram ranges of -40C to +125C, and consume just 500A of supply current. FAN FAIL V CC Applications Desktop Computers Servers TACH1 TH1 PWM THERMISTORS PWM1 GENERATOR Power Supplies REF AND LOCAL AND TACH TACH2 TEMP SENSOR Networking Equipment COUNTER TH2 PWM2 Workstations OT SMBus SCL INTERFACE SMBus is a trademark of Intel Corp. AND LOGIC GPIO0* REGISTERS SDA GPIO5* Typical Application Circuits and Pin Configurations appear at PRESET* end of data sheet. MAX6615 MAX6616 GND ADD0 ADD1 *MAX6616 ONLY Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs ABSOLUTE MAXIMUM RATINGS All Voltages Are Referenced to GND Continuous Power Dissipation (T = +70C) A Supply Voltage (V ) ...............................................-0.3V to +6V 16-Pin QSOP (derated at 8.3mW/C CC PWM , TACH , OT, FAN FAIL............................-0.3V to +13.5V above +70C)............................................................666.7mW ADD0, ADD1, SDA, SCL ..........................................-0.3V to +6V 24-Pin QSOP (derated at 9.5mW/C All Other Pins..............................................-0.3V to (V + 0.3V) above +70C)...........................................................761.9 mW CC SDA, OT, FAN FAIL, PWM , GPIO Current....................50mA ESD Protection (all pins, Human Body Model) ....................2kV TH Current ........................................................................1mA Operating Temperature Range .........................-40C to +125C REF Current ......................................................................20mA Junction Temperature......................................................+150C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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 = 0C to +125C, unless otherwise noted. Typical values are at V = +3.3V, T = +25C.) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Supply Voltage V 3.0 5.5 V CC Standby Current Interface inactive, ADC in idle state 10 A Operating Current I Interface inactive, ADC active 0.5 1 mA S V = +3.3V, 0.15V V +0.71V (excludes CC TH External Temperature Error 1 C thermistor errors, thermistor nonlinearity) (Note1) V = +3.3V, 0C T +85C, 2.5 CC A Internal Temperature Error C V = +3.3V, 0C T +125C 4 CC A Temperature Resolution 0.125 C Conversion Time 250 ms Conversion Rate Timing Error -20 +20 % PWM Frequency Error -20 +20 % INPUT/OUTPUT Output Low Voltage V V = +3V, I = 6mA 0.4 V OL CC OUT Output High Leakage Current I 1A OH Logic Low Input Voltage V 0.8 V IL Logic High Input Voltage V 2.1 V IH Input Leakage Current 1A Input Capacitance C 5pF IN SMBus TIMING (Figures 2, 3) (Note 2) Serial Clock Frequency f 10 400 kHz SCLK Clock Low Period t 10% to 10% 4 s LOW Clock High Period t 90% to 90% 4.7 s HIGH Bus Free Time Between STOP t 4.7 s BUF and START Conditions SMBus START Condition t 90% of SCL to 90% of SDA 4.7 s SU:STA Setup Time 2 MAX6615/MAX6616