DS18B20 digital temperature sensors are extremely popular among both electronics hobbyists and commercial manufacturers. Many applications require these sensors to be used in a waterproof, encapsulated form factor inside a protective metal sleeve. However, there are several prevalent issues with the cheap, pre-packaged sensors currently flooding the market:
- The use of substandard or counterfeit sensor ICs by suppliers (most commonly, these fake chips fail to operate correctly in the 2-wire “parasitic power” mode);
- The use of cheap wiring with a maximum temperature rating that is significantly lower than the sensor’s actual measurement range.
As a result of these supply chain issues, it can be incredibly difficult to source high-quality, reliable waterproof sensors in sufficient volumes at a reasonable price.
One highly effective solution is the custom in-house manufacturing of encapsulated sensors. This guarantees the use of authentic, high-quality ICs combined with structural materials (wires, potting compounds) that actually meet the required technical specifications. Material specifications can be carefully tailored based on the specific operating and storage environments of the final device, optimizing the balance between performance and cost. Ideally, the thermal rating of all materials used in the probe assembly should slightly exceed the maximum measurement range of the sensor itself; however, such high-temperature materials (like Teflon or silicone cables) are expensive. A more pragmatic, cost-effective approach is adopted: for specific B2B clients, custom batches are produced using materials that safely cover their exact required operating environment. For the general market, probes are manufactured with parameters that safely cover or closely match the standard measurement range of the DS18B20 chip.
