USB Thermometer

Digital thermometer probe with USB connection, based on genuine DS18B20 1–wire sensor and USB bridge interface, provides 9-bit to 12-bit temperature measurements. Each thermometer has an unique 64-bit serial code stored inside ROM.

Perfect solution for monitoring air temperature at home, in a greenhouse or in a server room. Measurements are more accurate since the temperature sensor is not in the same housing as the USB plug. Despite sensor's wide measuring range it is advisable its usage between –20 and +85 degrees Celsius. Unit of readout value (Celsius or Fahrenheit) depends on software used.

Models (configurations)

Here are listed values of default USB thermometer configuration, depending on selected USB bridge interface: PL2303GL or CP2102N.

Plug (shell) color: indigo (blue), white or black (PL2303GL); magenta (CP2102N)
Cable length (between plug and sensor): approximate 82 cm – 2.7 ft (PL2303GL); 92 cm – 3.0 ft (CP2102N)

These values could be changed on request, e.g. put probe on longer or shorter cable, or make it waterproof (IP68) by putting the sensor inside a stainless steel or copper tube, so that the temperature of a liquid, e.g. water in a swimming pool, could be measured.

Picture of normal version (with default configuration)

picture of waterproof (stainless steel) version, picture of waterproof (copper) version

Technical data

Measuring range: −55 °C — +125 °C (−67 °F — +257 °F)
Accuracy: 0.5 °C (0.9 °F) (from −10 °C to +85 °C), 2 °C otherwise
Resolution: 0.0625 °C (0.1125 °F) at 12-bit
Data record frequency: above 750 milliseconds at 12-bit
Works under Linux™ with kernel version at least 5.5 (Debian 11+, Fedora 32+, Mageia 8+, Manjaro 20.2.1+, OpenWrt 22.03+, Raspberry Pi OS 2022-04-04+, Rosa 12+, Ubuntu 20.10+ etc.) and Windows® 7, 8, 8.1, 10 and 11. CPU architecture independent: works also on MIPS and ARM (e.g. Raspberry Pi) and Android devices (which support USB host mode).
Supported by dedicated open source software (released under MIT license) at github.com/usbtemp (C, C++, C#, node.js and python 3 libraries with examples), UTMP Basic, and wide range of third-party tools and monitoring utilities, e.g. Digitemp, owfs, LogTemp, pydigitemp, usbtemp-server.

Note: This information describes the current, 2^nd generation of USB thermometer based on PL2303GL integrated circuit available after 10^th June 2022. Product sheet of previous generation

More information

Drivers and software

Prolific (PL2303) driver for Windows (ver. 2.0.4), (ver. 1.20) (from prolific.com.tw)
Silabs CP2102N driver for Windows 11 & 10, for Windows 7 & 8 (from silabs.com)
Maxim 1-wire driver 32-bit, 64-bit (for Windows from Analog)

digitemp.exe (ver. 1.7) (from digitemp.com)
Maxim 1-wire viewer for Windows (needs Maxim 1-wire driver & Java RTE) (from Analog)
LogTemp (ver. 2.25) (needs Maxim 1-wire driver) (from MR Soft)
utmp-cli for Windows, for Linux x86-64, for Linux ARM32 (from utmp-cli latest binary release), @openSUSE

Support

Technical support is available on mail support@[this domain].

There is officially no support for PL2303TA, used in previous generation of USB thermometer, in Windows 11, but there is a workaround by using older driver (offered on this website) and disabling Windows Update driver updates.

Buy

USB Thermometer (PL2303GL, normal: indigo plug and 82 cm cable; waterproof IP68: black plug, stainless steel shell 30mm x 6mm OD, and 92 cm cable) could be ordered securely online with PayPal.

Orders with value (excl. shipping & handling) greater than 25 EUR (27 USD) will be shipped with tracking number, otherwise 1.5 EUR (1.6 USD) will be refunded and shipped as priority (airmail). Shipping is flat rate (does not depend on the number of items ordered). Having both version inside the same cart might be expressed as double amount for the shipping & handling at the checkout. Second amount (and in case of two or more orders on the same day) will be refunded after purchase at order review.

Terms of purchase

Note: 1^st generation of USB thermometer based on PL2303TA integrated circuit is still available in limited quantity for legacy applications, and older operating systems, e.g. OpenWrt 19.07, Raspbian.

For cost clarification, customizations, different USB thermometer configuration, SEPA payment or business purchase please write to sales@[this domain] to review feasibility and delivery options.