Section _ Understanding (Darlington transistor ) or Darlington pair
Review of the Darlington transistor (Darlington pair) (how it works and uses)
Researcher and author: Dr. ( Afshin Rashid)
These transistors are often used for switching (turning on and off).
These types of transistors do not perform well at voltages below 3 volts, but for voltages above 3 volts, they turn on completely with very low current and go into saturation.
Power: Power Darlington transistors are usually used to connect a large consumer such as a motor to a microcontroller or a weak output with an hfe of at least 750 with a continuous current tolerance of 8 amps (you must take care to keep the transistor cool. At a minimum, use a heat sink and silicone paste or paper).
Darlington Transistor Operation:
A Darlington pair behaves like a single transistor with a high current gain (approximately the product of the gains of the two transistors).
Darlington pair as a transistor:
A Darlington pair can be used as a transistor with a large β in emitter follower circuits. Darlington pairs with β of about 30000 are commercially available on integrated circuits. An example of such a transistor is the MJ1000. The MJ1000 is a power Darlington transistor with a β of about 1000, a current-carrying capability of 10 A, and a collector-emitter voltage tolerance of up to 80 V.
Application of Darlington transistor
In many electronic applications, control circuits only need to switch a DC voltage or current on and off directly, because the components connected to their outputs, such as LEDs and displays, require a few milliamperes of DC power to operate at low DC voltages, so they can be driven directly by the output of standard logic gates. Sometimes we need more power to drive an output, such as when we want to drive a DC motor, which can be powered by a regular logic gate or microcontroller. If the logic components cannot provide the required current, we will need additional circuitry to drive the desired output.
Researcher and author: Dr. ( Afshin Rashid)
Specialized PhD in Nano-Microelectronics