Match the reference to the application.
The host supports the documented DHT22 frame and timing. Check the temperature and humidity requirements together with the installed airflow path.
Review the specification →GUILCOR · Digital sensing
DHT22 / AM2302
digital temperature and humidity sensor
DHT22 commonly refers to the AM2302 temperature and humidity family. Its timed data frame includes both readings and a checksum, allowing the host to reject a corrupted transfer before displaying a value.
Understand the reference
Validate the checksum before using the two channels.
The frame contains humidity, signed-magnitude temperature and an 8-bit additive checksum. A valid checksum establishes transfer consistency, not calibration or that the physical conditions have settled.
SELECTION / YOUR APPLICATION
Is DHT22 / AM2302 the right starting point?
Review DHT11 alongside DHT22 / AM2302.
Compare the humidity and temperature channels, host interface, electrical requirements and installation. The enclosure and exposure of the sensing opening are part of the selection.
Explore DHT11 →Keep the complete specification together.
Keep the exact device and host-driver references. Check commands, data conversion, connector and protective opening as well as the required measurement interval.
Prepare your enquiry →These links support a specification review. They do not establish interchangeable parts or availability of a complete assembly.
Interactive application guide
Decode and validate a measurement frame.
Enter five bytes in hexadecimal, in transmission order. The supplied example is the manufacturer example. Negative temperature uses a sign bit, not a signed two-complement word.
Relative humidity
Temperature
Frame integrity
Enable JavaScript to use this guide.
checksum = (byte0 + byte1 + byte2 + byte3) mod 256
Technical reference
Reference details for the application.
| Interface | Timed single-data-line transfer; not UART |
|---|---|
| Reference supply | AM2302 manual: 3.3 to 5.5 V |
| Read interval | At least 2 seconds; observe startup and freshness requirements |
| Frame / coding | 5 bytes; 0.1 °C and 0.1 % RH encoded steps |
| Operating interval | −40 to +80 °C; humidity limits and errors depend on conditions |
Apply the limits to the right component.
The sensing IC, finished probe and host electronics have separate requirements. Cable insulation, sealing, connector, supply and mounting may impose a narrower operating range. A temperature step is not an accuracy guarantee, and an electronic conversion time is not a thermal response time.
Use airflow and material selection suitable for humidity sensing. Condensation, contamination and board heating affect the result; the small encoded step is not the accuracy specification.
Wiring and integration
Specify the electrical interface and sensing path.
Device connections
Use the AM2302 timing and release the data line as required. Match the pullup and host voltage. Respect the minimum read interval and remember that the transfer can represent the previous measurement.
Host and installation checks
Match the electrical levels and the actual protocol at both ends. Confirm signal direction, grounding, pinout and any required transceiver. The interface name alone does not determine cable length, immunity or sensor accuracy.
Plan startup, conversion completion, timeout and recovery. Check integrity information where provided and retain the time of the last valid acquisition. Successful communication does not prove that the physical measurement has settled.
Acquisition sequence
Make each reading traceable.
Discover
Confirm the part, interface, supply and measurement mode.
Convert
Issue the device-specific command and satisfy its timing and power needs.
Validate
Read the correct registers, check CRC where provided and reject invalid or stale results.
Use
Apply the correct decoder or compensation, units and application limits.
Measurement quality
Separate electrical behaviour from thermal performance.
Accuracy and calibration
Choose the error limit over the actual operating interval. Add installation and readout effects. Define any calibration and periodic verification required by the application; factory calibration does not establish a universal no-maintenance policy.
Response and mounting
A sheath, potting material and mounting contact change how fast the sensing element follows the medium. Verify response in the intended flow and installation, rather than using conversion time as the finished-probe response.
Power and self-heating
Average dissipation depends on supply, conversion duty and surrounding electronics. Test the assembled probe at the intended reading rate. Do not assume a universal self-heating offset from the interface name.
Form factor library
Choose your probe format.
Choose the shape and mounting for the measurement point. These are GUILCOR probe families and a design service; confirm the compatible element, dimensions, cable and complete assembly for the selected reference.
Frequently asked questions
Questions before specifying the assembly.
Can the sensor be read continuously as fast as the host can poll?
No. The cited AM2302 manual requires at least 2 seconds between reads. Respect startup timing and distinguish the previous measurement from a newly completed one.
Are serial sensor interfaces interchangeable?
No. Match the electrical levels, protocol, timing and commands for the actual reference. Similar connector shapes or wire counts do not establish compatibility.
Does the interface determine measurement accuracy?
No. The sensor, conversion circuit, calibration and installation determine the measurement performance. Specify these separately from the communication interface.
What should I send for a probe quotation?
Send the reference and full ordering code, measured quantities, operating interval, error and response requirements, mounting drawing, cable and connector, host interface and quantity.
Technical sources
Continue with the reference documents.
GUILCOR / YOUR ENQUIRY
Define your DHT22 / AM2302 enquiry.
Describe both the electrical interface and the air reaching the sensor. Include the enclosure, airflow and exposure conditions when requesting an assembled probe.
Missing a reference or datasheet?
Send the component marking, equipment reference and any photographs or documents you have. These provide a starting point for identifying what must be confirmed.
The outline helps prepare your enquiry. Copying it does not send a request.
FOUR DETAILS THAT MOVE THE DISCUSSION FORWARD
01
Device and host
Exact device or module, interface, host or driver, supply and logic levels, addressing or wiring and measurement commands.
02
Measurement conditions
Temperature and humidity intervals, required accuracy and update rate, airflow, condensation risk, contamination and any additional measured quantities.
03
Assembly and connection
Sensing opening or filter, enclosure and ventilation, mounting location, nearby heat sources, connector and cable arrangement.
04
Project and validation
Sample and production quantities, target delivery, calibration or documentation needs, and the checks required before approval.