SBOSA15B September 2022 – January 2025 TMP1827
PRODUCTION DATA
The TMP1827 can operate as a 1-Wire® half duplex bus, either in supply or bus powered mode. The TMP1827 features a thermal sensor with an integrated 2Kb user EEPROM and SHA-256-HMAC authentication for applications requiring identification with lesser number of components due to space constraints. The device also features an integrated CRC that can be used for verifying data integrity during communication.
The bus powered mode is designed for applications working without a dedicated power supply pin and can reduce cabling costs. As the device current consumption during thermal conversion and EEPROM operations is low, the device can not require a low impedance current path, thereby reducing the need for additional FET or load switch and current limiting resistor to bypass the bus pullup resistor. The pullup resistor used during bus powered mode must be correctly sized to verify that the sufficient current can be supplied during a thermal conversion and EEPROM operation, and input pin voltage does not fall below the VIH(MIN).
Additionally, if the host must reset the device when operating in bus powered mode, the host must pull the communication line low for at least 50 ms. This allows the internal capacitor of the device to discharge and prepare the device for power-on reset.