{"product_id":"uln2803apg-8-channel-darlington-transistor-array-18-pin-dip-package","title":"ULN2803APG (8-Channel Darlington Transistor Array - 18-Pin DIP Package)","description":"\u003cp data-path-to-node=\"5\"\u003eA standard Arduino Uno or ESP32 GPIO pin can safely output roughly 20 to 40 milliamps of current. If you attempt to connect a mechanical relay, a solenoid valve, or a stepper motor directly to your microcontroller, you will instantly destroy the pin. The \u003cb data-path-to-node=\"5\" data-index-in-node=\"255\"\u003eULN2803\u003c\/b\u003e is the industry-standard silicon \"muscle\" that solves this problem. It is an array of eight independent NPN Darlington transistor pairs. You send a weak, safe 5V logic signal from your microcontroller into one side of the chip, and the corresponding transistor on the other side acts as a heavy-duty switch, capable of handling up to 500mA and 50V.\u003c\/p\u003e\n\u003cp data-path-to-node=\"6\"\u003eWhat makes the ULN2803 an absolute staple on the workbench is its convenience. If you were to build this circuit manually, you would need 8 transistors, 8 base resistors, and 8 flyback diodes—cluttering your breadboard with 24 separate components. The ULN2803 packages all of this into a single 18-pin chip. It includes built-in base resistors perfectly tuned for 5V logic, and integrated flyback (freewheeling) diodes on every channel to safely absorb the destructive voltage spikes generated when turning off inductive loads like motors and relays. Because it has exactly 8 channels, it is the legendary companion chip to the 74HC595 shift register, allowing you to build massive, digitally controlled power stations.\u003c\/p\u003e\n\u003cp data-path-to-node=\"7\"\u003e\u003cb data-path-to-node=\"7\" data-index-in-node=\"0\"\u003eKey Features \u0026amp; Functional Advantages:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"8\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,0,0\"\u003e\u003cb data-path-to-node=\"8,0,0\" data-index-in-node=\"0\"\u003e8 Independent High-Power Channels:\u003c\/b\u003e Perfectly mapped for 8-bit digital logic, allowing you to control a full byte's worth of heavy loads from a single IC.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,1,0\"\u003e\u003cb data-path-to-node=\"8,1,0\" data-index-in-node=\"0\"\u003eMassive Load Capacity:\u003c\/b\u003e Each individual channel can switch up to 50V and sink up to 500mA. (Note: For thermal safety, if turning all 8 channels on simultaneously, the current per channel should be kept much lower).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,2,0\"\u003e\u003cb data-path-to-node=\"8,2,0\" data-index-in-node=\"0\"\u003eBuilt-in Inductive Protection:\u003c\/b\u003e Features integrated clamping diodes tied to a common \"COM\" pin. This safely routes high-voltage kickback from spinning motors and clicking relays away from your sensitive logic.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,3,0\"\u003e\u003cb data-path-to-node=\"8,3,0\" data-index-in-node=\"0\"\u003eIntegrated Base Resistors:\u003c\/b\u003e The \"2803\" specifically features 2.7kΩ input resistors, meaning you can wire the input pins directly to standard 5V TTL logic (like an Arduino) without adding any external resistors.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,4,0\"\u003e\u003cb data-path-to-node=\"8,4,0\" data-index-in-node=\"0\"\u003eBreadboard Native (18-DIP):\u003c\/b\u003e Sized perfectly to straddle the center gap of a standard solderless breadboard for rapid, tidy prototyping.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-path-to-node=\"9\"\u003e\u003cb data-path-to-node=\"9\" data-index-in-node=\"0\"\u003ePerfect For:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"10\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,0,0\"\u003e\u003cb data-path-to-node=\"10,0,0\" data-index-in-node=\"0\"\u003eRelay Expansion Modules:\u003c\/b\u003e The absolute standard silicon used to drive banks of 4, 8, or 16 mechanical relays from a single microcontroller.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,1,0\"\u003e\u003cb data-path-to-node=\"10,1,0\" data-index-in-node=\"0\"\u003eUnipolar Stepper Motors:\u003c\/b\u003e Excellent for driving classic 5-wire or 6-wire unipolar steppers (like the ubiquitous 28BYJ-48 motor).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,2,0\"\u003e\u003cb data-path-to-node=\"10,2,0\" data-index-in-node=\"0\"\u003eSolenoid \u0026amp; Valve Control:\u003c\/b\u003e Easily handles the heavy current spikes required to snap open automated water valves or pneumatic solenoids in smart agriculture projects.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,3,0\"\u003e\u003cb data-path-to-node=\"10,3,0\" data-index-in-node=\"0\"\u003eHigh-Power LED Arrays:\u003c\/b\u003e A highly reliable way to PWM-dim long strips of 12V or 24V single-color LEDs without overloading your Arduino.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-path-to-node=\"11\"\u003e\u003cb data-path-to-node=\"11\" data-index-in-node=\"0\"\u003eTechnical Specifications:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"12\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,0,0\"\u003e\u003cb data-path-to-node=\"12,0,0\" data-index-in-node=\"0\"\u003eTransistor Type:\u003c\/b\u003e NPN Darlington Array\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,1,0\"\u003e\u003cb data-path-to-node=\"12,1,0\" data-index-in-node=\"0\"\u003eNumber of Channels:\u003c\/b\u003e 8\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,2,0\"\u003e\u003cb data-path-to-node=\"12,2,0\" data-index-in-node=\"0\"\u003eMaximum Output Voltage:\u003c\/b\u003e 50V DC\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,3,0\"\u003e\u003cb data-path-to-node=\"12,3,0\" data-index-in-node=\"0\"\u003eMaximum Output Current:\u003c\/b\u003e 500mA per channel (Sink)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,4,0\"\u003e\u003cb data-path-to-node=\"12,4,0\" data-index-in-node=\"0\"\u003eInput Logic Compatibility:\u003c\/b\u003e 5V TTL\/CMOS (Contains internal 2.7kΩ resistors)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,5,0\"\u003e\u003cb data-path-to-node=\"12,5,0\" data-index-in-node=\"0\"\u003eIntegrated Protection:\u003c\/b\u003e Built-in Flyback Diodes\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,6,0\"\u003e\u003cb data-path-to-node=\"12,6,0\" data-index-in-node=\"0\"\u003ePackage \/ Case:\u003c\/b\u003e 18-DIP (0.300\", 7.62mm width)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,7,0\"\u003e\u003cb data-path-to-node=\"12,7,0\" data-index-in-node=\"0\"\u003eMounting Type:\u003c\/b\u003e Through-Hole (PTH)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"K-TECHNICS","offers":[{"title":"Default Title","offer_id":42865889706055,"sku":null,"price":0.0,"currency_code":"KES","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0680\/7637\/2039\/files\/32_480x384_3ca388d4-e102-457b-a418-eacf4bc32614.webp?v=1781086794","url":"https:\/\/www.ktechnics.com\/products\/uln2803apg-8-channel-darlington-transistor-array-18-pin-dip-package","provider":"K-TECHNICS","version":"1.0","type":"link"}