Temp-Log 7 Click Board™

How Does The Temp-Log 7 Click Board™ Work?

The Temp-Log 7 Click Board™ is based on the TMP1826, a digital output temperature sensor from Texas Instruments designed for thermal management and protection applications. The TMP1826 features an integrated 2-kbit user EEPROM that allows the host to store application data in increments of 64 bits. With a user-programmable 256-bit page size write protection to avoid accidental overwrite, the EEPROM can be used as non-volatile, read-only memory. The TMP1826 also features an integrated CRC that may be used for ensuring data integrity during communication. It consists of an internal thermal BJT (NIST traceable factory-programmed non-erasable), a high-resolution analog-to-digital converter (ADC), and a data processing circuit in one package. The voltage is digitized and converted to a 16-bit temperature result in degrees Celsius, giving a digital output with outstanding accuracy of up to ±0.1°C (typical)/±0.3°C (maximum) and temperature resolution of 7.8125m°C, typical over a temperature range of –20°C to +85°C.

This Click board™ communicates with MCU using the 1-Wire interface that, by definition, requires only one data line (and ground) for communication with MCU. The 1-Wire communication line is routed to the SMD jumper labelled GP SEL, which allows routing of the 1-Wire communication either to the GP0 pin or the GP1 pin of the mikroBUS™ socket. These pins are labelled, respectively, the same as the SMD jumper positions, making the selection of the desired pin simple and straightforward. The TMP1826 can operate as a 1-Wire half-duplex bus in supply or bus-powered mode. Selection is made by positioning the SMD jumper marked VDD SEL to the appropriate position labelled VCC or GND. With the jumper set on the VCC position, the TMP1826 is powered by the same supply as this Click board™ or bus powered with the jumper set on the GND position where the device is supplied parasitically from the 1-Wire bus.

Also, the TMP1826 can be configured to operate in various one-shot temperature-conversion modes, such as basic one-shot, auto, and stacked conversion modes. Each conversion mode has a single temperature sample, but the host can enable 8 sample averages in the device for improved accuracy. Depending on the user application case, the TMP1826 also provides user and application configurable address modes. These modes exist alongside the standard device address and are useful for applications requiring faster access and device position identification. One of the ways of setting the address is through the R9 resistor, which, depending on the value of the resistor, provides the possibility of using one of 16 addresses.

The TMP1826 also includes advanced features like a programmable alarm function and three digital I/O pins on an unpopulated header, configurable for general purposes or to identify the device's position on a shared bus. An alarm (interrupt) signal, routed to the ALR pin of the mikroBUS™ socket, is alarming when a specific temperature event occurs that depends on the value of the temperature reading relative to programmable limits.

The Temp-Log 7 Click Board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout of the Temp-Log 7 Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

ONBOARD SETTINGS AND INDICATORS

TEMP-LOG 7 CLICK ELECTRICAL SPECIFICATIONS