Counterfeit DS18B20 temperature sensors

DS18B20 temperature sensor counterfeit vs. real
On the left, a relabeled transistor; on the right, an actual DS18B20.

As anyone who’s wanted to measure temperature with a Raspberry Pi knows, it doesn’t offer analog input. This means that the TMP36 sensor which is commonly used with the Arduino doesn’t work. The most popular option for the Pi then is the DS18B20, which is a digital sensor that utilizes the 1-wire interface and is natively supported by the Pi. It’s considerably more expensive than the TMP36, and as is the case when a component is expensive and in-demand, it’s prone to counterfeiting. I recently experienced this firsthand.

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