Please contact our sales support for information on specific devices. Distributor reported inventory date: This browser is out of date and not supported by st.
As a result, you may be unable to access certain features. Consider that modern browsers:. So why not taking the opportunity to update your browser and see this site correctly? You can start following this product to receive updates when new Resources, Tools and SW become available. It's easy and takes only 1 minute. You can re-use the validation code to subscribe to another product or application. Search History Bookmark Please log in to show your saved searches.
Save to MyST. Online design. CAD Resources. Partner products. Sales Briefcase. Quick links. Latest update. All dates. Product overview.
They are designed to supply more than 1. The nominal output voltage is selected by means of a resistive divider, making the device exceptionally easy to use and eliminating the stocking of many fixed regulators. All features Output voltage range: 1. Read more Read less. Recommended for you. Your browser does not support JavaScript. Some components may not be visible.
Quality and Reliability. More Info. Marketing Status Active. Package TO Grade Industrial. Package D2PAK. Package TOFP. The LM78xx series of regulators is quite famous throughout the world and are frequently used in millions of electronics-based projects.
The 78xx series consists of the following regulators. The 78 represents the series while the last two digits represent the voltage. Although we have this much variety of the voltage regulators then why we need the LM adjustable regulator? There are some factors like the 78xx series of regulators give you the fixed voltage.
I have been using the voltage regulator for powering up the family microcontrollers, ATmega, and sensors that need 5 volts. The maximum of the sensors which are used with the Arduino are low power devices and they can be powered up using the voltage regulator.
Another voltage regulator from the same series which is ; I have been using this voltage regulator for powering up a 12v relay and some small DC motors. No matter how many regulators are invented the 78xx series will always stay cool. There are situations when we need variable voltage for example a workbench power supply. Or you are working on a project where you need 3. In a situation like this 78xx series of regulators fail to work or you will need complex circuit designing which trusts me nobody likes.
A few months back I was working on a project in which I had to control the home appliance over wifi using the ESP Wifi module. If you check the datasheet of the ESP wifi module you will come to know that this module needs 3. Although, the Arduino was able to provide 3. In a situation like this for me, the best choice was to use the LMt adjustable variable voltage regulator. So this tutorial is all about how to design a variable power supply using the LMt voltage regulator. You can also download the datasheet of the LMt by clicking on the download button given below.
Download: LMt datasheet: LM datasheet. The LM is an adjustable 3-terminal positive voltage regulator capable of supplying in excess of 1. This voltage regulator is exceptionally easy to use and requires only two external resistors to set the output voltage. Further, it employs internal current limiting; thermal shutdown and safe area compensation, making it essentially blow-out proof. The output voltage of the LMt variable adjustable voltage regulator is determined by the ratio of two resistors R1 and R2 which basically forms a voltage divider circuit across the output terminal of the lmt voltage regulator.
The voltage across the feedback resistor R1 is constant 1. The current is constant at the adjustment terminal which is uA. Since the reference voltage Vref across the resistor R1 is constant, so a constant currnet I will flow through the other resistor R2, which results in an output voltage which can be calculated using the following formula. The input voltage Vin to the LMt must be at least 2. The voltage regulator LMt has a very good load regulation providing that the minimum load is greater than 10mA.
Now to maintain a constant reference voltage Vref of 1. Of course in practice, the resistor R2 is normally replaced by a potentiometer so as to produce the variable voltage. Before starting the practical connections first I checked my connections in the Proteus Simulation software. This is the final circuit after soldering. As you can see this circuit only has 4 components, a variable resistor which is R2 in the circuit diagram, a ohm resistor represented by R1 in the circuit diagram, and a 33uf capacitor.
These components are explained in the video given below. This Final circuit is exactly as per the circuit diagram explained above. I connected the input power supply and at the output, I connected a digital multimeter. I was able to vary the voltage by rotating the knob of the variable resistor. So this project was a great success.
I designed this power supply for powering up my ESP Wifi module.
0コメント