4N25 is a General Purpose Optocoupler. This bolg covers 4N25 Optocoupler pinout, datasheet, equivalent, features and other information on how to use and where to use this device.
Catalog
4N25 CAD Model
4N25 Symbol
4N25 Footprint
4N25 3D
4N25 Pinout
Pin NO.
|
Pin Name
|
Pin Description
|
1
|
Anode
|
IR LED Anode/ Positive Pin
|
2
|
Cathode
|
IR LED Cathode/ Negative Pin
|
3
|
NC
|
Not Connected Pin
|
4
|
Emitter
|
Base Pin of the Photo Transistor
|
5
|
Collector
|
Collector Pin of the Photo Transistor
|
6
|
Base
|
Emitter Pin of the Photo Transistor
|
4N25 Applications
The 4N25 is widely used in many electronic applications because of its advanced features and characteristics. Following are some applications 4N25 optocoupler is used for.
- Solid State Relays
- I/O Interfacing
- General Purpose Switching Circuit
- Reed Relay Driving
- AC mains detection
- Logic Ground Isolation
- Telephone ring detection
- Switch mode power supply feedback
- Motor drive and control
- Communication and networking
- Power management
4N25 Features
- IR LED Forward Voltage for turning ON: 1.25V-1.5V (Typically 1.3V, 1.5V being absolute maximum forward voltage)
- IR LED Forward Current during ON: 10mA - 60mA (Typically 10mA, 60mA being absolute maximum forward current)
- IR LED Reverse Voltage Maximum: 5V
- IR LED Reverse Current Maximum: 100uA
- Maximum voltage across COLLECTOR and EMITTER of TRANSISTOR: 70V
- Maximum current allowed trough TRANSISTOR COLLECTOR: 100mA
- Typical Rise Time: 2us
- Typical Fall Time: 2us
- No additional power needed to be applied for chip for making it work.
4N25 Advantage
4N25 General Purpose Optocoupler
4N25 is also a widely used optocoupler / optoisolator / photocoupler, It is a general purpose optocoupler like PC817, MOC3021 etc. It is manufactured in 6 pin dip package and SMD package. The device consists of one IR LED and one phototransistor / Detector which detects the light comes from the IR LED.
4N25 also having the base pin of the detector transistor connected with the pin6 of the body, hence the user can control transistor by two inputs one from the IR LED light which is connected to pin1 and pin2 and other from controlling the transistor with its base.
The phototransistor can handle max 30V and max150mA across it collector-emitter. Moreover the collector-emitter saturation voltage is from 0.15 to 0.5 which is ideal to use in applications where voltage saturation is required. The max forward current of the IR LED is 60 milliampere and the max power dissipation of the IR LED is 120 milliwatt. The pin3 is a NC pin that is also shown in the 4N25 pinout or pin diagram above “NC” means it is not connected with the internal circuitry of the device.
4N25 Equivalent
4N25 replacement and equivalent optocouplers are 4N26, 4N28, PC817, PC816, 4N27, 4N35, 4N36 & H11Ax series.
4N25 Package
- Package Dimensions in millimeters
4N25 Parameters
Brand
|
Vishay Semiconductors
|
Configuration
|
1 Channel
|
Current Transfer Ratio
|
50 %
|
Height
|
3.81 mm
|
If - Forward Current
|
60 mA
|
Isolation Voltage
|
5000 Vrms
|
Length
|
8.7 mm
|
Manufacturer
|
Vishay
|
Maximum Collector Current
|
100 mA
|
Maximum Collector Emitter Saturation Voltage
|
0.5 V
|
Maximum Collector Emitter Voltage
|
70 V
|
Maximum Operating Temperature
|
+ 100 C
|
Minimum Operating Temperature
|
- 55 C
|
Mounting Style
|
Through Hole
|
Number of Channels
|
1 Channel
|
Output Type
|
NPN Phototransistor
|
Package / Case
|
DIP-6
|
Packaging
|
Tube
|
Pd - Power Dissipation
|
150 mW
|
Product Category
|
Transistor Output Optocouplers
|
Product Type
|
Transistor Output Optocouplers
|
Series
|
4N2x
|
Subcategory
|
Optocouplers
|
Unit Weight
|
0.012346 oz
|
Vf - Forward Voltage
|
1.5 V
|
Vr - Reverse Voltage
|
5 V
|
Width
|
6.5 mm
|
4N25 Documents
4N25 Product Compliance
USHTS
|
8541408000
|
CAHTS
|
8541400091
|
CNHTS
|
8541409000
|
KRHTS
|
8541409029
|
MXHTS
|
85414001
|
TARIC
|
8541409090
|
ECCN
|
EAR99
|
Why to Use 4N25 optocoupler
For understanding the use of optocoupler consider:
- Case 1: where you want to isolate load circuit from control circuit. Say you want to control the speed of a small DC motor by using microcontroller PWM output. This setup is not feasible as microcontroller is sensitive device. So for isolating load circuit and protecting the controller from voltage fluctuations we use optocoupler.
- Case 2: Say you want to trigger a MOSFET circuit which is driving a high power load. The MOSFET trigger voltage typically is 12V. These voltages bursts (+12V) needed for MOSFET driver to control the high power load cannot be draw from controller. As controller puts out +3.3V or +5V bursts. In those cases using 4N25 optocoupler chip is ideal.
- Case 3: Consider we want to switch a 12V relay which is looping 220V AC fan according to RASPBERRY PI outputs. It is ideal to use 4N25 in this case, as 4N25 draws negligible amount of power considering a transistor or a MOSFET.
4N25 Circuit
4N25 Switching Schematic
How to Safely Long Run 4N25 in a Circuit
To get long term performance with this device it is suggested that the user should always stay below the absolute max ratings. The maximum load the device can handle is 150mA therefore do not connect load more than 150mA. Always use a suitable current limiting resistor with the IR LED. Always operate in temperature above -55 centigrade and below +100 centigrade and store in temperature above -55 centigrade and below +150 centigrade.
How to Use 4N25 Optocoupler
Using 4N25 optocoupler is pretty straight forward; this optoisolator contains 6 pins as shown in the above 4N25 pinout diagram. The LED side of this or any other optoisolator is connected just like any other normal LED like Anode pin with the positive and cathode pin with the negative or ground. Now connected the Anode pin (Pin1) with the output you want to use the output should be positive and the cathode pin (Pin2) be should be connected with negative or ground of the same circuit. Now the other part of the device which is the phototransistor, the phototransistor have two base one is connected with the photo detector which detects the IR LED light and switches ON the transistor and the second one is connected with pin 6 which also switches ON the transistor when current is applied on the base. Hence the phototransistor can be operated like a general BJT transistor and also like a phototransistor or the user can also use the transistor in both ways for example one signal output is connected with the IR LED and the other signal output is connected with the base of the transistor.
Where to Use 4N25 Optocoupler
4N25 optocoupler can be used for variety of purposes and requirements in electronic circuits. For example it can be used in electronic applications where there is a chance of voltage surge or spikes which most of the time damage the electronic circuits and components due to which it can be used for the safety of the components. The photocoupler isolates one circuit from the other so you can use it easily when there is a requirement of isolation between two circuits. Apart from this it can also be used as voltage detector in AC and DC operated circuits, output of microcontroller to operate other devices and applications from microcontrollers, controlling relay, controlling MOSFET and other high power transistors, high voltage circuits, controlling AC and DC high voltages etc.
4N25 Popularity by Region
4N25 Market Price Analysis
4N25 Manufacturer
Vishay Semiconductors includes the former Vishay Telefunken product lines, the former General Semiconductor product lines, the infrared component product lines acquired from Infineon Technologies, and selected product lines acquired from International Rectifier (excluding planar high-voltage MOSFETs).
The Vishay Semiconductors product portfolio includes rectifiers, fast-recovery diodes, high-power diodes and thyristors, small-signal diodes, Zener and suppressor diodes, RF transistors, optoelectronics, power modules (a combination of power diodes, thyristors, MOSFETs, and IGBTs), and automotive modules and assemblies.
Vishay is the world's number one manufacturer of rectifiers, glass diodes, and infrared components.
Component Datasheet
4N25 Datasheet
FAQ
4N25 is a General Purpose Optocoupler.
- What package is 4N25 manufactured in?
6 pin dip package and SMD package
- How many IR LEDs does 4N25 consist of?
One IR LED and one phototransistor / Detector