{"product_id":"bc547-npn-transistor-45v-100ma-to-92-for-switching-amplification","title":"BC547 NPN Transistor – 45V 100mA TO-92 for Switching \u0026 Amplification","description":"\u003ch1\u003eBC547 Transistor\u003c\/h1\u003e\n\u003cp\u003eThe BC547 is an NPN bipolar junction transistor in a compact TO-92 package. It handles up to 100mA of collector current and 45V across collector-emitter, making it a versatile choice for low-power switching and small-signal amplification in embedded and hobbyist circuits.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTransistor Type\u003c\/td\u003e\n\u003ctd\u003eNPN BJT\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMax Collector-Emitter Voltage (Vce)\u003c\/td\u003e\n\u003ctd\u003e45V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMax Collector Current (Ic)\u003c\/td\u003e\n\u003ctd\u003e100 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDC Current Gain (hFE)\u003c\/td\u003e\n\u003ctd\u003e110 to 800 (group‑dependent)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePackage\u003c\/td\u003e\n\u003ctd\u003eTO-92\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePinout (flat face)\u003c\/td\u003e\n\u003ctd\u003eCollector, Base, Emitter (left to right)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/arduino-pwm-led-dimmer-kit-beginner-project\"\u003eArduino-based LED flasher or dimmer using PWM\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eSimple audio preamplifier for a microphone module\u003c\/li\u003e\n  \u003cli\u003eRelay or small DC motor driver with flyback protection\u003c\/li\u003e\n  \u003cli\u003eTouch‑activated switch or rain sensor circuit\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThe BC547 works with any microcontroller platform that provides base drive voltage above 0.7 V, including Arduino (5 V logic) and Raspberry Pi (3.3 V logic with appropriate base resistor). It pairs easily with other common TO-92 transistors like the BC557 (PNP complement) and with signal diodes, resistors, and small relays.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eAlways use a base resistor (1 kΩ typical for 5 V logic) to limit base current. Connect the emitter directly to ground, place the load between collector and the positive supply, and ensure the collector current stays below 100 mA to avoid permanent damage.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-5 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes. Connect a 1 kΩ resistor between the Arduino digital pin and the base, ground the emitter, and place your load (like an LED with its own resistor) between the collector and 5 V.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I identify the pins?\u003c\/summary\u003e\u003cp\u003eHold the transistor with the flat face toward you and the pins pointing down. The pins are, from left to right: Collector (C), Base (B), Emitter (E).\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I use it to drive a relay directly?\u003c\/summary\u003e\u003cp\u003eYes, as long as the relay coil current is under 100 mA. Place a flyback diode across the coil to protect the transistor from voltage spikes when switching off.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445153882477,"sku":"CDN-0896","price":300.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/image_1_06ce8559-3832-43af-ad9f-6e9706ce6c16.jpg?v=1781513542","url":"https:\/\/compoden.com\/products\/bc547-npn-transistor-45v-100ma-to-92-for-switching-amplification","provider":"Compoden","version":"1.0","type":"link"}