A1273 Transistor Pinout, Applications, Equivalents, Features and More

A1273 or 2SA1273 which is its full part number is a PNP transistor available in TO-92L package. In this post we are going to explore A1273 transistor pinout, applications, equivalents, features and many other related information about this transistor.

Features / Technical Specifications

• Package Type: TO-92L Or TO-92MOD
• Transistor Type:  PNP
• Max Collector Current(I_C): -2A
• Max Collector-Emitter Voltage (V_CEO): -30V
• Max Collector-Base Voltage (V_CBO): -30V
• Max Emitter-Base Voltage (V_EBO): -5V
• Max Collector Dissipation (P_C): 1W
• Max Transition Frequency (f_T): 120 MHz (TYP)
• Minimum & Maximum DC Current Gain (h_FE): 100 – 320
• Max Storage & Operating temperature Should Be: -55 to +150 Centigrade

NPN Complimentary:

The NPN complimentary of 2SA1273 is 2SC3205

Replacement and Equivalent:

KTA1273, 2SB1076, 2SB1229, KTA1241, KTA1282, 2SB1288, 2SB1306, 2SB892, 2SB985 (These are the nearest possible replacement or equivalent of A1273 transistor but some of these transistors may have a different pin configuration than the 2SA1273 so it is recommended to check the pin configuration before replacing it in your circuit or design.

2SA1273 Transistor Explained / Description

A1273 is a silicon PNP transistor available in TO-92L or TO-92MOD (Both are same) package. This package is slightly longer in height as compared to TO-92 package. When viewed from the front side (part number side) of the transistor, the first pin of the transistor is “Emitter”, the second is “Collector” and the third is “Base”.

Although the transistor is designed to use in audio power amplifier applications but due to its versatile electrical characteristics it can also be used in a variety of other applications. Such as it has a collector current of -2A which makes it ideal to drive many loads in electronic circuits. It also has an acceptable DC current gain of 100-320 which provides good quality audio amplification, moreover, it also has a transition frequency of 120MHz which makes it capable to use in RF circuits under 120MHz.

Looking at the maximum ratings of the transistor the max collector-base voltage is -30V, max collector-emitter voltage is -30V, max emitter-base voltage is -5V, max collector current is -2A and max collector dissipation is 1W.

This transistor is available in two different hFE types. The transistor’s part number is followed by an alphabetic code by which we can determine the hFE. If the code is “O” then the hFE will be 100-200 and if the code is “Y” then the hFE will be 160-320.

Where We Can Use it & How to Use

A1273 transistor is mainly designed to use in audio power amplifiers but other than that it can also be used for a variety of other purposes such as in switching circuits, RF circuits, and also in many other general purpose applications. The detailed list of its applications can be found below under the “Applications” heading.

Applications

Audio Amplifiers

Motor Driver

Solar Circuits

Automotive Circuits

Various Types of RF Circuits under 120MHz

Switching Applications

Variety of General Purpose Applications

Safe Operating Guidelines

To safely operate the transistor do not use it to its absolute maximum ratings and always stay at least 20% below from its max ratings. So the maximum collector current is -2A therefore according to the 20% safety rule the driven load should be not more than -1.6A or 1600mA, the maximum collector-emitter voltage is -30V therefore the driven load voltage should be under 24V and storage and operating temperature of the transistor should be between -55°C to 150°C.

Datasheet

To Download the datasheet just copy and paste the below link in your browser.

https://z3d9b7u8.stackpathcdn.com/pdf-down/2/S/A/2SA1273-KEC.pdf