The MAX31820 ambient temperature sensor provides 9-bit to 12-bit Celsius temperature measurements with ±0.5°C accuracy over a +10°C to +45°C temperature range. Over its entire -55°C to +125°C operating range, the device has ±2.0°C accuracy. The device communicates over a 1-Wire® bus that, by definition, requires only one data line (and ground) for communication with a central microprocessor. In addition, the device can derive power directly from the data line (“parasite power”), eliminating the need for an external power supply. Requiring so few pins enables the device to be placed in a 3-pin TO-92 package. The form factor of this package allows the device to be placed above the board and thus measure the ambient temperature of a system, as opposed to the board temperature that a surface-mount package would measure. Each MAX31820 has a unique 64-bit serial code, which allows multiple MAX31820 devices to function on the same 1-Wire bus. Therefore, it is simple to use one microprocessor to control many devices distributed over a large area.ApplicationsAny Thermally Sensitive SystemConsumer ProductsHVAC Environmental ControlsIndustrial SystemsProcess Monitoring and Control SystemsTemperature Monitoring Systems Inside Buildings, Equipment, or MachineryThermometersThermostatic Controls

The MAX6639 monitors its own temperature and one external diode-connected transistor or the temperatures of two external diode-connected transistors, typically available in CPUs, FPGAs, or GPUs. The 2-wire serial interface accepts standard System Management Bus (SMBus) write byte, read byte, send byte, and receive byte commands to read the temperature data and program the alarm thresholds. Temperature data can be read at any time over the SMBus, and three programmable alarm outputs can be used to generate interrupts, throttle signals, or overtemperature shutdown signals.The temperature data is also used by the internal dual-PWM fan-speed controller to adjust the speed of up to two cooling fans, thereby minimizing noise when the system is running cool, but providing maximum cooling when power dissipation increases. Speed control is accomplished by tachometer feedback from the fan, so that the speed of the fan is controlled, not just the PWM duty cycle. Accuracy of speed measurement is ±4%.The MAX6639 is available in 16-pin QSOP and 16-pin thin QFN 5mm x 5mm packages. It operates from 3.0V to 3.6V and consumes just 500µA of supply current.ApplicationsDesktop ComputersNetworking EquipmentNotebook ComputersProjectorsServers

The DS1626 and DS1726 digital thermometers/thermostats provide temperature measurements and stand-alone thermostat capability over a -55°C to +125°C range. The DS1626 offers ±0.5°C accuracy from 0°C to +70°C and the DS1726 has ±1°C accuracy from -10°C to +85°C. The resolution of the measured temperature is user selectable from 9 to 12 bits. Communication with the DS1626 and DS1726 is achieved through a 3-wire serial bus.The DS1626 and DS1726 offer thermostatic functionality with three dedicated thermostat outputs (THIGH, TLOW, and TCOM), and overtemperature (TH) and undertemperature (TL) user-programmable thresholds stored in on-chip EEPROM. For stand-alone thermostat operation, TH and TL can be programmed prior to installation, and the DS1626/DS1726 can be configured to automatically begin taking temperature measurements at power-up. Table 1, in the full data sheet, summarizes the user-accessible registers. Figure 1, in the full data sheet, shows a functional diagram.ApplicationsAny Space-Constrained Thermally Sensitive ApplicationConsumer ProductsIndustrial ControlsThermostatic Controls

The DS1626 and DS1726 digital thermometers/thermostats provide temperature measurements and stand-alone thermostat capability over a -55°C to +125°C range. The DS1626 offers ±0.5°C accuracy from 0°C to +70°C and the DS1726 has ±1°C accuracy from -10°C to +85°C. The resolution of the measured temperature is user selectable from 9 to 12 bits. Communication with the DS1626 and DS1726 is achieved through a 3-wire serial bus.The DS1626 and DS1726 offer thermostatic functionality with three dedicated thermostat outputs (THIGH, TLOW, and TCOM), and overtemperature (TH) and undertemperature (TL) user-programmable thresholds stored in on-chip EEPROM. For stand-alone thermostat operation, TH and TL can be programmed prior to installation, and the DS1626/DS1726 can be configured to automatically begin taking temperature measurements at power-up. Table 1, in the full data sheet, summarizes the user-accessible registers. Figure 1, in the full data sheet, shows a functional diagram.ApplicationsAny Space-Constrained Thermally Sensitive ApplicationConsumer ProductsIndustrial ControlsThermostatic Controls

Board Mount Temperature Sensors Remote Temperature Switch

The DS7505 low-voltage (1.7V to 3.7V) digital thermometer and thermostat provides 9-, 10-, 11-, or 12-bit digital temperature readings over a -55°C to +125°C range with ±0.5°C accuracy over a -0°C to +70°C range. A 9-bit resolution mode is software compatible with the LM75.The DS7505 thermostat has a dedicated open-drain output (O.S.) and programmable fault tolerance, which allows the user to define the number of consecutive error conditions that must occur before O.S. is activated. There are two thermostatic operating modes that control thermostat operation based on user-defined trip points (TOS and THYST) that are stored in EEPROM registers.ApplicationsAny Thermally Sensitive SystemCellular Base StationsMedical EquipmentNetworking EquipmentOffice Equipment

The DS7505 low-voltage (1.7V to 3.7V) digital thermometer and thermostat provides 9-, 10-, 11-, or 12-bit digital temperature readings over a -55°C to +125°C range with ±0.5°C accuracy over a -0°C to +70°C range. A 9-bit resolution mode is software compatible with the LM75.The DS7505 thermostat has a dedicated open-drain output (O.S.) and programmable fault tolerance, which allows the user to define the number of consecutive error conditions that must occur before O.S. is activated. There are two thermostatic operating modes that control thermostat operation based on user-defined trip points (TOS and THYST) that are stored in EEPROM registers.ApplicationsAny Thermally Sensitive SystemCellular Base StationsMedical EquipmentNetworking EquipmentOffice Equipment

This low-voltage (1.7V to 3.7V) digital thermometerand thermostat provides 9, 10, 11, or 12-bit digitaltemperature readings over a -55°C to +125°C rangewith ±2°C accuracy over a -25°C to +100°C range. Atpower-up, the DS75LX defaults to 9-bit resolution forsoftware compatibility with the LM75. Communicationwith the DS75LX is achieved through a simple 2-wireserial interface. Three tri-state address pins allow upto 27 DS75LX devices to operate on the same 2-wirebus, which greatly simplifies distributed temperature-sensingapplications.The DS75LX thermostat has a dedicated open-drainoutput (O.S.) and programmable fault tolerance,which allow the user to define the number ofconsecutive error conditions that must occur beforeO.S. is activated. There are two thermostaticoperating modes that control thermostat operationbased on user-defined trip-points (TOS and THYST).ApplicationsAny Thermally Sensitive SystemCellular Base StationsServersTelecom Switches and Routers

This low-voltage (1.7V to 3.7V) digital thermometerand thermostat provides 9, 10, 11, or 12-bit digitaltemperature readings over a -55°C to +125°C rangewith ±2°C accuracy over a -25°C to +100°C range. Atpower-up, the DS75LX defaults to 9-bit resolution forsoftware compatibility with the LM75. Communicationwith the DS75LX is achieved through a simple 2-wireserial interface. Three tri-state address pins allow upto 27 DS75LX devices to operate on the same 2-wirebus, which greatly simplifies distributed temperature-sensingapplications.The DS75LX thermostat has a dedicated open-drainoutput (O.S.) and programmable fault tolerance,which allow the user to define the number ofconsecutive error conditions that must occur beforeO.S. is activated. There are two thermostaticoperating modes that control thermostat operationbased on user-defined trip-points (TOS and THYST).ApplicationsAny Thermally Sensitive SystemCellular Base StationsServersTelecom Switches and Routers

The MAX6695/MAX6696 are precise, dual-remote, and local digital temperature sensors. They accurately measure the temperature of their own die and two remote diode-connected transistors, and report the temperature in digital form on a 2-wire serial interface. The remote diode is typically the emitter-base junction of a common-collector PNP on a CPU, FPGA, GPU, or ASIC.The 2-wire serial interface accepts standard system management bus (SMBus) commands such as Write Byte, Read Byte, Send Byte, and Receive Byte to read the temperature data and program the alarm thresholds and conversion rate. The MAX6695/MAX6696 can function autonomously with a programmable conversion rate, which allows control of supply current and temperature update rate to match system needs. For conversion rates of 2Hz or less, the temperature is represented as 10 bits + sign with a resolution of +0.125°C. When the conversion rate is 4Hz, output data is 7 bits + sign with a resolution of +1°C. The MAX6695/MAX6696 also include an SMBus timeout feature to enhance system reliability.Remote temperature sensing accuracy is ±1.5°C between +60°C and +100°C with no calibration needed. The MAX6695/MAX6696 measure temperatures from -40°C to +125°C. In addition to the SMBus active-low ALERT output, the MAX6695/MAX6696 feature two overtemperature limit indicators (active-low OT1 and active-low OT2), which are active only while the temperature is above the corresponding programmable temperature limits. The active-low OT1 and active-low OT2 outputs are typically used for fan control, clock throttling, or system shutdown.The MAX6695 has a fixed SMBus address. The MAX6696 has nine different pin-selectable SMBus addresses. The MAX6695 is available in a 10-pin µMAX® and the MAX6696 is available in a 16-pin QSOP package. Both operate throughout the -40°C to +125°C temperature range.ApplicationsDesktop ComputersNotebook ComputersServersTest and Measurement EquipmentWorkstations