*data = byte; return true;
If you are building a battery-powered ESP8266 or ESP32 project, the YL105 is the better datasheet choice. Part 3: The "Better" Way to Read Timing Diagrams (Critical Datasheet Section) Most users fail with the YL105 because they ignore the timing diagram. To make your YL105 perform better than a cheap library default, you must understand these values:
This article breaks down the YL105 datasheet in detail and explains exactly where, why, and how this sensor is than its more famous rivals. Part 1: What is the YL105? (A Datasheet Overview) Before we discuss "better," we need a baseline. The YL105 is a digital temperature and humidity sensor module. Unlike the raw DHT11, the YL105 comes pre-soldered onto a PCB with a built-in pull-up resistor and a filtering capacitor. Key Specifications from the YL105 Datasheet: | Parameter | Value | Why it matters | | :--- | :--- | :--- | | Operating Voltage | 3.3V to 5.5V | Better compatibility (works with 3.3V ESP32 & 5V Arduino) | | Humidity Range | 20% to 90% RH | Standard room conditions | | Humidity Accuracy | ±5% RH | Comparable to DHT11 | | Temperature Range | 0°C to 50°C | Indoor/Greenhouse focused | | Temperature Accuracy | ±2°C | Adequate for HVAC monitoring | | Sampling Rate | 1 Hz (1 reading per second) | Better stability than cheap clones | | Signal Type | Single-bus digital | Uses only 1 GPIO pin | yl105 datasheet better
The YL105 datasheet reveals a sensor that is better for 80% of hobbyist and commercial indoor projects . It is robust, forgiving, and cheap. When paired with proper timing code and a clean power supply, it rivals sensors twice its price.
When you are searching for the term you aren't just looking for pinouts and voltage ratings. You want a comparative analysis. You want to know: Why should I choose the YL105 over the DHT11, DHT22, or the AM2302? *data = byte; return true; If you are
Stop fiddling with external pull-ups and faulty libraries. Download the original YL105 datasheet, follow the timing diagrams above, and build humidity logging that just works. YL105 Arduino wiring, YL105 vs DHT22 latency, YL105 humidity calibration offset, best YL105 library GitHub
#define YL105_PIN 2 void startSignal() pinMode(YL105_PIN, OUTPUT); digitalWrite(YL105_PIN, LOW); delay(20); // Better: 20ms (exceeds 18ms requirement) digitalWrite(YL105_PIN, HIGH); delayMicroseconds(40); pinMode(YL105_PIN, INPUT); Part 1: What is the YL105
| Parameter | Symbol | Value | Your code must... | | :--- | :--- | :--- | :--- | | Start signal low time | Tbe | > 18 ms | Pull pin LOW for 20ms (not 1ms) | | Sensor response low | Trel | 80 µs | Wait for pin to go LOW | | Sensor response high | Treh | 80 µs | Wait for pin to go HIGH | | Bit "0" high time | Tbit_0 | 24-28 µs | Sample after 30 µs | | Bit "1" high time | Tbit_1 | 70-74 µs | Sample after 50 µs |