{"product_id":"humidity-sensor-humidity-to-frequency-output","title":"Humidity Sensor – Humidity to Frequency Output","description":"\u003cp\u003e\u003cspan\u003eThis sensor board provides frequency output as per relative humidity value. The project is based on a unique capacitive cell, this relative humidity sensor is designed for high volume, cost-sensitive applications such as office automation, automotive cabin air control, home appliances, and industrial process control systems. It is also useful in all applications where humidity compensation is needed. The circuit is built using a low-cost \u003c\/span\u003e\u003cstrong\u003eNE555\u003c\/strong\u003e\u003cspan\u003e timer as an astable generator, humidity sensor \u003c\/span\u003e\u003cstrong\u003eMK1\u003c\/strong\u003e\u003cspan\u003e acts as a variable capacitor and is connected to the \u003c\/span\u003e\u003cstrong\u003eTRIG\u003c\/strong\u003e\u003cspan\u003e and \u003c\/span\u003e\u003cstrong\u003eTHRES\u003c\/strong\u003e\u003cspan\u003e pin. Pin 7 is used as a short circuit pin for resistor R3. The \u003c\/span\u003e\u003cstrong\u003eHS1101LF\u003c\/strong\u003e\u003cspan\u003e equivalent capacitor is charged through R2, R3, and PR1 is set the threshold voltage (approximately 0.67Vcc) and discharged through R2 only to the trigger level (approximately 0.33Vcc) since R3 is shortened to the ground by pin 7. Since the charge and discharge of the sensor run through two different resistors, R2 and R3, the duty cycle is determined by the following formulas.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eSupply 5V (Range 5 to 10V DC)\u003c\/li\u003e\n\u003cli\u003eCurrent 10mA\u003c\/li\u003e\n\u003cli\u003eFrequency Output 10% RH =7155 Hz to 95% RH =6210\u003c\/li\u003e\n\u003cli\u003eDuty Cycle Approx. 50%\u003c\/li\u003e\n\u003cli\u003eHigh reliability and long-term stability\u003c\/li\u003e\n\u003cli\u003eFast response time and very low temperature coefficient\u003c\/li\u003e\n\u003cli\u003eFull interchangeability with no calibration required in standard conditions\u003c\/li\u003e\n\u003cli\u003ePCB Dimensions 38.89MM X 16.99MM\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"dotfry","offers":[{"title":"Default Title","offer_id":47247450374316,"sku":null,"price":12.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0757\/6436\/7532\/files\/S143A.jpg?v=1789816233","url":"https:\/\/dotfry.com\/products\/humidity-sensor-humidity-to-frequency-output","provider":"dotfry","version":"1.0","type":"link"}