Transistors - Programmable Unijunction

Category Introduction

Programmable unijunction transistors (PUTs) are a relative of Silicon Controlled Rectifier (SCR) devices, having a characteristic behavior somewhat like a unidirectional DIAC with a user-configurable threshold voltage. While useful for creating low frequency oscillator and timing functions, SCR triggering applications, and others, alternative techniques for addressing such needs have gained greater favor.

Product List

13 Items

Mfr Part #	Quantity Available	UnitPrice	Packaging	Product Status	Voltage	Power Dissipation (Max)	Voltage - Output	Voltage - Offset (Vt)	Current - Gate to Anode Leakage (Igao)	Current - Valley (Iv)	Current - Peak	Package / Case
2N6027 PBFREE PROGRAMMABLE UJT 40V TO226-3 Central Semiconductor Corp	335	$1.20	Bulk	Active	40V	300 mW	6V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA)
2N6028 PBFREE PROGRAMMABLE UJT 40V TO226-3 Central Semiconductor Corp	714	$1.23	Bulk	Active	40V	300 mW	6V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA)
2N6027RLRA THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	98	$0.00	Cut Tape (CT)	Obsolete	40V	300 mW	11V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6028RLRA THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	513	$0.00	Cut Tape (CT)	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6027RLRAG THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	388	$0.00	Tape & Reel (TR)	Obsolete	40V	300 mW	11V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6028RLRAG THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	275	$0.00	Tape & Reel (TR)	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6027G TRANS PROG UNIJUNCT 40V TO92 onsemi	450	$0.00	Box	Obsolete	40V	300 mW	11V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA)
2N6027RL1 THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	594	$0.00	Tape & Reel (TR)	Obsolete	40V	300 mW	11V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6028G THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	551	$0.00	Bulk	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA)
2N6028RLRP THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	237	$0.00	Tape & Box (TB)	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6027RL1G THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	54	$0.00	Tape & Reel (TR)	Obsolete	40V	300 mW	11V	1.6 V	10 nA	50 µA	2 µA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6028RLRMG THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	608	$0.00	Cut Tape (CT)	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads
2N6028RLRPG THYRISTOR PROG UNIJUNCT 40V TO92 onsemi	184	$0.00	Cut Tape (CT)	Obsolete	40V	300 mW	11V	600 mV	10 nA	25 µA	150 nA	TO-226-3, TO-92-3 (TO-226AA) Formed Leads

About Programmable Unijunction Transistors (PUTs)

What are Programmable Unijunction Transistors (PUTs)?

Programmable Unijunction Transistors (PUTs)

Programmable Unijunction Transistors (PUTs) are a type of semiconductor device that functions as a switch or amplifier in electronic circuits. Unlike traditional unijunction transistors, PUTs offer the advantage of programmability, allowing users to set the intrinsic standoff ratio through external resistors. This flexibility makes them ideal for applications requiring precise control over switching characteristics. PUTs operate by utilizing a four-layer structure (PNPN) and are triggered into conduction when the anode voltage exceeds a certain threshold, determined by the gate voltage. This makes them suitable for timing, triggering, and oscillator circuits.

Types of Programmable Unijunction Transistors (PUTs)

Standard PUTs

Standard PUTs are the most common type, used in general-purpose applications. They are characterized by their simplicity and ease of use, making them suitable for educational purposes and basic circuit designs. These PUTs are often employed in relaxation oscillators and timing circuits.

High-Voltage PUTs

High-voltage PUTs are designed to handle higher voltage levels, making them ideal for industrial applications where robust performance is required. These PUTs are used in power control circuits and high-voltage triggering applications, where they provide reliable switching capabilities.

Low-Power PUTs

Low-power PUTs are optimized for applications where energy efficiency is crucial. They consume less power and are used in battery-operated devices and low-power oscillators. Their reduced power consumption makes them suitable for portable electronics and energy-saving applications.

How to choose Programmable Unijunction Transistors (PUTs)?

When selecting a PUT, consider the following key parameters:

Voltage Rating: Ensure the PUT can handle the maximum voltage in your application.
Current Rating: Choose a PUT with a current rating that matches your circuit's requirements.
Gate Sensitivity: Select a PUT with appropriate gate sensitivity for your triggering needs.
Temperature Range: Consider the operating temperature range to ensure reliability in your environment.

Evaluate product quality by reviewing supplier certifications, customer reviews, and testing standards. Consider environmental factors such as humidity and temperature fluctuations, and ensure proper installation with adequate heat dissipation and protection against electrical noise.

Applications of Programmable Unijunction Transistors (PUTs)

Consumer Electronics

In consumer electronics, PUTs are used in timing circuits for devices like televisions and radios. They help manage power supply timing and ensure efficient operation of electronic components.

Industrial Automation

PUTs play a crucial role in industrial automation systems, where they are used in control circuits for machinery and equipment. Their ability to handle high voltages makes them suitable for robust industrial environments.

Automotive Industry

In the automotive sector, PUTs are employed in ignition systems and timing circuits. They help improve the efficiency and reliability of vehicle electronics, contributing to better performance and fuel efficiency.

Telecommunications

PUTs are used in telecommunications for signal processing and timing applications. They ensure accurate timing and synchronization in communication networks, enhancing data transmission reliability.

Medical Devices

In medical devices, PUTs are used in monitoring and diagnostic equipment. Their precise timing capabilities are essential for accurate measurements and reliable operation of medical instruments.