Yl105 Datasheet

YL105 Datasheet: A Complete Guide to the 5V Single-Channel Relay Module

Introduction

In the world of electronics and microcontroller projects (Arduino, Raspberry Pi, ESP8266, STM32), the ability to control high-power devices—such as lamps, motors, solenoids, and pumps—using low-power logic signals is essential. The YL105 is one of the most popular and widely available single-channel relay modules designed precisely for this purpose.

YL‑105 (typical module) — key specs

• Function: Digital temperature & humidity sensor module (often based on SHT1x/SHT2x or DHT series in clones; confirm variant)
• Supply voltage: 3.3–5.5 V (commonly 5 V tolerant)
• Interface: Digital single-wire or two-wire serial (depends on underlying IC)
• Typical current draw: idle <1 mA, measurement pulses higher (tens of mA peak)
• Accuracy: humidity ±3–5% RH (typical), temperature ±0.3–0.5 °C (depends on IC)
• Measurement range: humidity 0–100% RH, temperature −40 to +80 °C (IC-dependent)
• Response time: tens of seconds for humidity (tau ~8–30 s)
• Operating temp: −40 to +85 °C (typical)

Common YL-series modules (Arduino/electronics): yl105 datasheet

1. Voltage regulator – powers the Hall plate and signal conditioning.
2. Hall plate – generates millivolt signals in response to magnetic flux.
3. Differential amplifier – amplifies the tiny Hall voltage.
4. Schmitt trigger – provides hysteresis for noise-free switching.
5. Open-collector output – sinks current when activated.

C. Voltage Reference Instability

The LM393 comparator uses the potentiometer voltage and the sensor’s output. The datasheet fails to mention that the potentiometer is not a precision reference—it drifts with temperature and vibration. Your digital trigger point will change over time. YL105 Datasheet: A Complete Guide to the 5V