MAX6615 MAXIM [Maxim Integrated Products], MAX6615 Datasheet
MAX6615
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MAX6615 Summary of contents
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... The MAX6616 is available in a 24-pin QSOP package, while the MAX6615 is available in a 16-pin QSOP pack- age. Both devices operate from a single-supply voltage range of 3.0V to 5.5V, have operating temperature ranges of -40°C to +125°C, and consume just 500µA of supply current. ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs ABSOLUTE MAXIMUM RATINGS All Voltages Are Referenced to GND Supply Voltage (V ) ...............................................-0.3V to +6V CC PWM_, TACH_, OT, FAN_FAIL ............................-0.3V to +13.5V ADD0, ADD1, SDA, SCL ..........................................-0.3V to +6V ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs ELECTRICAL CHARACTERISTICS (continued +3.0V to +5.5V 0°C to +125°C, unless otherwise noted. Typical values are PARAMETER SYMBOL START Condition Hold Time t HD:STO ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs (V = +3.3V +25°C, unless otherwise noted GPIO SINK CURRENT vs. SUPPLY VOLTAGE 0.4V GPIO_ 3.0 3.5 ...
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... Fan Tachometer Input. Accepts logic-level signal from fan’s tachometer output. Can be connected to a supply voltage as high as 12V, regardless of the supply voltage. SMBus Slave Address Selection SMBus Slave Address Selection Ground. Must be connected together for MAX6615. External Thermistor Input 1. Connect a thermistor in series with a fixed resistor between REF and ground. No Connection Reference Voltage Output ...
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... GPIO PRESET input to ground SMBus Digital Interface From a software perspective, the MAX6615/MAX6616 appear as a set of byte-wide registers. Their devices use 2 a standard SMBus 2-wire/I C-compatible serial interface to access the internal registers. The MAX6615/MAX6616 6 _______________________________________________________________________________________ ACK COMMAND ACK — 8 BITS — COMMAND BYTE: SELECTS ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs HIGH LOW SMBCLK SMBDATA t t SU:STA HD:STA A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs Table 1. Temperature Data Format (High Byte and Low Byte) TEMPERATURE (°C) BINARY VALUE 140.0 127.0 25.375 25.0 0.5 0.0 <0 ture. The thermistor data in the temperature register(s) gives the ...
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... Figure 5. Driving a Fan with a PWM-to-DC Circuit V CC 4.7kΩ PWM Figure 6. Controlling a PWM Input Fan with the MAX6615/ MAX6616s’ PWM Output (Typically, the 35kHz PWM Frequency Is Used) brushless DC motor has enough time to operate. When driving a fan with a PWM-to-DC circuit as shown in Figure 5, the highest available frequency (35kHz) should be used to minimize the size of the filter capacitors ...
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... At power-on, or when the POR bit in the configuration byte register is set, the MAX6615/MAX6616 have the default settings indicated in Table 3. Some of these set- tings are summarized below: • ...
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... GPIO3, GPIO4, GPIO5 1ms Figure 8. Power-On GPIO States ______________________________________________________________________________________ The MAX6615/MAX6616 contain 32/34 internal regis- ters. These registers store temperature data, allow con- trol of the PWM outputs, determine if the devices are ADDRESS measuring from the internal die or the thermistor inputs, 0011 000 and set the GPIO as inputs or outputs ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs Table 3. Register Map POR R/W ADD FUNCTION STATE 0000 Temperature R 00h 0000 channel 1 0000 Temperature R 01h 0000 channel 2 0001 C onfi g ur ati on R/W ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs Table 3. Register Map (continued) POR R/W ADD FUNCTION STATE PWM1 instantan- 0000 R 0Dh 000x eous duty cycle PWM2 instantan- 0000 R 0Eh 000x eous duty cycle Channel 1 0000 ...
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... Selects either local or remote 2 as the source for temperature channel 2 register data. When the MAX6615/MAX6616 measure remote 2 and when the MAX6615/MAX6616 measure the internal die temperature. Set spin-up disable disable spin-up. Set to zero for normal fan spin-up. ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs zero, the duty cycle is zero below the fan-start tempera- ture and has this value when the fan-start temperature is reached. A value of 240 represents 100% duty cycle. Writing any ...
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... SELECT C Tachometer Value Registers (18h and 19h) The tachometer value registers contain the tachometer 0 0 count values for each fan. The MAX6615/MAX6616 measure the tachometer signal every 67s. It counts the 1 0 number of clock cycles between two tachometer pulses 0 ...
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... IC. However, by connecting the thermistor in series with a properly chosen resistor and using the MAX6615/MAX6616 to measure the voltage across the resistor, a reasonably linear transfer function can be obtained over a limited temperature range. Accuracy increases over smaller temperature ranges. ...
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... TH1 9 N.C. 10 REF 11 TH2 12 Typical Application Circuits V CC (5V OR 12V) 10kΩ V FAN 3.0V TO 5.5V 4.7kΩ V FAN_FAIL CC TH1 PWM1 100pF MAX6615 TACH1 REF PWM2 100pF TH2 TACH2 V CC SDA 10kΩ SCL OT GND(5) GND(10) ADD0 ADD1 Pin Configurations 24 GPIO3 GPIO4 23 22 PWM2 TACH2 ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs BETATHERM 10K3A1 THERMISTOR 1.6kΩ 1.6kΩ BETATHERM 10K3A1 THERMISTOR TO SMBus MASTER ______________________________________________________________________________________ Typical Application Circuits (continued 10kΩ V FAN 3.0V TO 5.5V 4.7kΩ V FAN_FAIL CC TH1 PWM1 100pF ...
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Dual-Channel Temperature Monitors and Fan-Speed Controllers with Thermistor Inputs (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) Maxim cannot assume responsibility for use of any ...