TE Connectivity HTU21D (HPP845E031R1) Digital Humidity/Temperature Sensor
OEM calibrated digital relative humidity and temperature sensor in a 3 × 3 × 0.9 mm DFN package.
Original manufacturer: TE Connectivity (MEAS).
| Technology | I²C digital humidity and temperature |
|---|---|
| Manufacturer specifications | 0–100% RH; operating temperature −40 to +125°C |
| Ex rating | No ATEX/IECEx hazardous-area approval established for this OEM component. |
Official Manufacturer Data
TE original part-number page and current datasheets →
OEM sensing components are not complete certified industrial detectors; ordering suffix and hardware revisions determine exact specifications.
HTU21D — tiny DFN humidity/temperature component
The TE Connectivity HTU21D HPP845E031R1 is a calibrated digital RH/temperature component in a roughly 3 mm DFN case. It requires correct I²C host wiring and PCB humidity exposure; a fully encapsulated or heated electronics enclosure can prevent it from sampling representative air. The −40 to +125°C device temperature class is not proof of stable RH accuracy under sustained condensation. Do not treat a bare OEM chip as an industrial 4–20 mA humidity transmitter.
Source-based engineering specifications and selection
HPP845E031R1 identifies an HTU21D calibrated I²C humidity/temperature bare component packaged for automated PCB assembly. Do not silently replace this with the HTU21DF filtered-membrane variant or claim an IP67 rating for the unfiltered chip.
| Verified OEM detail | Engineering meaning |
|---|---|
| RH 0–100%; temperature −40 to +125°C overall device range | Operating limits are wider than the conditions for typical accuracy; avoid condensation and saturation claims without a system test. |
| HTU21D RH typical ±2%RH (20–80%RH); temperature typical ±0.3°C (5–60°C) | Condition-specific maker family figures, not absolute guarantees for every climate or board installation. |
| Digital I²C; selectable 8/12-bit through 12/14-bit RH/T modes; CRC/checksum; 3 × 3 × 0.9 mm DFN | Confirm conversion time/resolution, checksum handling, bus voltage and conformal-coating keep-out. |
| TE part HPP845E031R1; family includes separate HPP845E131R1 filter version | Ordering suffix specifies delivery/variant; verify exposed die vs protected-membrane construction. |
Integration and maintenance
Position the package in representative ambient airflow away from self-heating, adhesive solvents and humidifier spray. Provide moisture/condensation recovery time; the TE product status is shown as active but its individual online part page also states not currently available for direct purchase, which is not evidence of end-of-life. The device itself does not output a 4–20 mA signal or have an instrument-level Ex certificate.
Sources: TE part-specific page; TE HTU21D family technical description and variants.