DS18B20 1-Wire Temperature Sensors, Probes and Modules

DS18B20 digital temperature sensing: choose the actual part

Shop DS18B20 1-Wire digital thermometer ICs, stainless-tip cable probes, compact KY-001-style boards, probe-and-adapter kits and multi-channel temperature acquisition hardware. This collection preserves a broad group of related listings: it also contains empty protective sleeves, ESP8266 host accessories, finished thermostats, NTC and analog temperature alternatives, and unrelated pH/TDS or diagnostic items. A shared “Dallas 18B20” search term is a way to find the DS18B20 device family, not evidence that every selectable product is made by Dallas Semiconductor, Maxim or Analog Devices. Manufacturer, marking, provenance and authenticity require verification for the specific selected chip or assembly; listing phrases such as “original” alone do not establish them.

What a DS18B20 does, and what it does not

A DS18B20 measures temperature and communicates a digital result over a 1-Wire bus. It is not a linear analog-output LM35 or TMP36, a resistance-based NTC/PT100 probe, a humidity sensor, an I²C sensor or a Modbus instrument by itself. The device family supports addressable operation with unique identifiers and configurable conversion resolution; practical performance depends on electrical supply, bus timing, conversion wait, measurement point and the chosen physical assembly. Device literature commonly states a -55°C to +125°C sensing-element operating span, with accuracy specified for particular temperature intervals rather than as a blanket promise throughout the span. Do not transfer silicon ratings automatically to the cable jacket, encapsulant, connector, PCB or whole instrument. Some probe listings specify a narrower assembled limit such as -20°C to +80°C.

Search results sometimes mix DS18B20, DS18S20, DS1820 and “18B20” names. These names should not be treated as identical part numbers merely because a headline contains several. Confirm the marking and selected model before relying on a particular device command set, resolution or software library. A temperature reading is not humidity, dissolved-solids concentration or pH; any combined project needs separate sensors and appropriate signal interfaces.

Bare ICs versus packaged sensors

• Through-hole IC: TO-92 DS18B20 selections occur as one-, two-, five-, eight-, ten-, fifteen-, twenty-, fifty- or hundred-piece lots across different listings. The package is a loose semiconductor, not an installed waterproof probe, connectorized harness or display. Read quantity from the selected option rather than from another quantity in the product headline.
• Surface-mount alternatives: certain five-piece pages present DS18B20U MSOP-8, DS18B20Z SOP-8 and TO-92 as separate choices; other pages list SOP-8 in ten-piece form. Check footprint, pin assignment, soldering process and the exact suffix. A TO-92 photo is not proof that the chosen MSOP-8 or SOP-8 arrives in a leaded probe format.
• Mixed semiconductor menus: some “DS18B20” pages also offer LM35DZ, LM335Z, LM334Z, TMP36GT9Z, BS170, BS250, 2SK30A, KIA7042AP, DS1233, DS2431, DS2502 and DS2505 as independent variants. The selected LM35/TMP36 is an analog temperature IC; several other choices are not thermometers at all. A title listing multiple models describes possible choices, not a multipack containing every model.

Stainless-tip and lug-style cable probes

Stainless-tube probe choices range from about 0.5 m to 10 m in these listings, with common 1, 2, 3 and 5 m lengths. Some are one probe; others offer five or ten probes per selected lot, and a few pages combine length, connector version and pack quantity as separate option dimensions. Check all selected dimensions together. Some variants specify a 1 m PH2.0 connector, 2.5 mm or 2.54 mm styles, XH2.54 two- or three-position connectors, a three-pin line or bare/tinned leads. Similar connector pitch and cable color do not establish the same pinout. A 2-core probe must not be assumed to use the same supply wiring as a 3-core probe; confirm whether its documented mode is parasite-powered or uses a specific adapter before connecting a host.

Several variants offer a copper-lug probe with 4, 5, 6 or 8 mm mounting hole and selected 1 or 2 m shielded cable. These suit appropriate surface contact, subject to mounting and electrical validation; they are not mechanically interchangeable with a cylindrical immersion tip. Other products supply a 3.0 mm stainless-tube probe, a silicone-cable probe with a stated assembled temperature limit or a preterminated line. Confirm the sleeve diameter, hole size, cable sheath, lead length, probe count and mating connector against the installation.

“Waterproof” in a listing should not be read as an independently verified IP grade, unlimited immersion depth, pressure rating, food-contact suitability or chemical resistance. The metal tip, crimp, splice, cable jacket and connector may have different environmental limits. Protect exposed connections from condensation or liquid, and check the actual assembly's operating temperature rather than quoting a bare IC maximum for the whole harness. For oil or hot equipment, verify material compatibility and installation-specific limits before use.

Sensor modules, adapters and kits

Three-pin KY-001-style and other DS18B20 detection modules can place a sensor on a small PCB with pins for a controller; module listings include one-, five-, ten-, twenty- and thirty-piece selections. Verify the installed IC, pin labels, board operating voltage and whether a pull-up is already fitted. A module advertised as “DC 5V” is not automatically safe to drive a 3.3 V input without checking its data-line pull-up and the host's absolute limits.

Other listings distinguish “DS18B20 Adapter,” “Conversion module,” “Single Module,” “Individual module,” “Module,” “Module and Line,” “DS18B20 KIT,” “1M Cable Adapter,” “2M Cable Adapter” and “1 Set 1M cable.” These are different delivery levels: an adapter-only PCB might have no cabled sensor, while a cable-only selection may not include the PCB. A three-pin line module option differs from an individual probe wire. Treat the selected option and its specific bill of materials as authoritative; never infer that every option supplies both a sensor and a board because the page title says kit.

Empty stainless protective sleeves are also sold here for PT100/DS18B20 use, including 6×30, 6×50, 6×60, 6×120, 8×50 and 10×120 mm styles in selected ten-, fifty- or hundred-piece lots. Round-head and flat-head choices change the physical tube. A blind protection tube is an enclosure component, not a working sensor; confirm internal clearance, retention, sealing and thermal coupling if you intend to install your own probe.

Designing a reliable 1-Wire installation

A direct DS18B20 system needs a correctly identified data line, supply/reference arrangement and pull-up matched to the host logic voltage. Confirm exact lead orientation from the chosen package or probe documentation, not from a generic wire-color chart. Dedicated-power and parasite-power installations have different power-delivery constraints, particularly for conversions on long or heavily loaded buses. Do not presume that a two-conductor probe will work on an arbitrary three-wire breakout. Verify the controller's supported 1-Wire timing and conversion handling before committing a long harness to a site.

On a multi-drop bus, unique device addresses permit multiple sensors but do not remove cable capacitance, stub effects or interference. Plan topology, total length, connector quality, cable routing near switching loads and the pull-up for the real number of sensors. For each conversion, allow completion time at the selected resolution, check bus errors and disconnected/shorted conditions, and do not treat a stale or startup value as a valid temperature. Log the address-to-physical-location mapping so a replacement sensor does not silently become the wrong channel. A listed 10 m cable length describes the offered assembly; it does not guarantee an error-free 10 m multi-probe network on every host.

Measurement accuracy also depends on thermal installation. A stainless sleeve and cable introduce response delay and possible contact offset; a lug probe may be biased by mounting surface and ambient airflow. Test at the temperatures of interest against a suitable reference and assess self-heating, response time and repeatability. Configurable resolution is not a substitute for traceable calibration. For consequential heating or cooling equipment, use independent fault handling and overtemperature protection rather than trusting one bus reading as a safety mechanism.

RS485 acquisition and controller options

Two-channel DS18B20 collector pages offer “No terminal,” “With terminal,” “With Pin,” “No Pin” or a separate “DS18B20 Sensor” option. Eight-channel pages distinguish “Motherboard,” “Only Board,” “With DIN housing,” “1PCS 8CH Collector,” “2pcs DS18B20 Sensor” and “4PCS DS18B20 Sensor.” Sensor-only does not include the collector; board-only does not imply a probe on every input. Another selection offers 5 V or 12 V power with RS485 versus TTL232 output and TS/NO designations. Confirm the chosen board's voltage, supported probe count, terminal style, isolation claims, Modbus register map, baud settings and included sensors from its own documentation.

RS485 describes the serial electrical interface; Modbus RTU requires compatible framing and register interpretation. A direct GPIO 1-Wire sketch will not read an RS485 Modbus collector without appropriate serial hardware and software. Conversely, the collector may handle the 1-Wire sensors locally rather than exposing their raw bus. Some related converters are specifically for 10K B3950 NTC thermistors: an NTC input is not a DS18B20 1-Wire input, even if the page mentions replacement of other temperature probes. A PLC or paperless recorder requires the correct instrument protocol and power wiring, not just the right nominal temperature span.

Wireless accessories and finished devices

ESP8266 D1 mini, ESP-01 and ESP-01S multiproduct listings offer DS18B20 shields or sensor options beside DHT11/DHT22 humidity devices, SHT30/BMP180, OLED, relay, buzzer, WS2812, TF-card, battery and ESP8266 host-board variants. “D1 DS18B20,” “DS18B20” or “Relay With ESP-01S” is one selected item, not a package containing every pictured board. Read whether the controller, sensor, relay or shield actually ships. A DS18B20 measures temperature only, notwithstanding “temperature humidity” in a mixed-menu title.

Other entries include an AT89C2051 digital-temperature-controller kit, small two-wire display thermometers, AC 110/220 V thermostat models, a Tuya 220 V thermostat socket and a handheld oscilloscope/transistor tester that can identify or test DS18B20 devices. These are complete controllers, instruments or kits, not interchangeable 1-Wire probe modules. A mains thermostat's relay capacity, supply wiring and protective measures are specific to that unit; do not derive a universal mains-wiring procedure from a sensor collection.

Related measurements and misleading keyword combinations

TDS analog water-quality boards and PH4502C pH kits occur in the results. A pH menu includes “PH Module,” “PH Probe,” “Probe and Module,” “DS18B20 1m” and “Probe Module Cable” as distinct choices; a pH probe is not automatically a thermometer. TDS output is not DS18B20 digital temperature data. Another mixed probe listing presents BMP180, BMP280, BME280, BME680/BME688 and SGP30/SGP40 alternatives alongside DS18B20 and LM35DZ: these have different interfaces and measurands. A selected AHT20 transmitter supports a different temperature/humidity device from a DS18B20-only option. Use the exact option and the corresponding host interface rather than treating related search words as common specifications.

Before placing an order

1. Check the selected exact model, not just “Dallas,” “DS1820,” “18B20” or a collage of multiple IC numbers in the title. Confirm manufacturer provenance separately if it matters.
2. Identify the delivered level: bare TO-92/SOP-8/MSOP-8 IC, cabled probe, lug probe, mounted sensor module, adapter-only PCB, empty sleeve, complete kit, acquisition board, sensor-only spare or finished controller.
3. Confirm quantity, cable length, sheath, connector and pinout; “Color” often names a different device or bill of materials.
4. Match raw 1-Wire, TTL serial and RS485 Modbus to the actual host. Check supply voltage, data-line pull-up, timing, channel capacity and software support.
5. Use assembled-probe environmental limits and real installation testing. Do not treat “waterproof,” chip-level accuracy or a seller's authenticity adjective as a certified system-level guarantee.

The practical choice is the selected part that fits your electrical interface, mechanical mounting and measurement environment, not the broadest claim in a product headline.