Saturday, March 29, 2014

1W Amplifier With TDA 7052

Good evening everyone. This post is about another small audio amplifier that provides around 1.2W of output power and it requires no external component which makes this circuit very easy to make. This circuit can be used with battery operated devices.


1. No external component needed,
2. Good overall stability,
3. Low power consumption,
4. No on/off click sound,
5. No heat-sink needed.
6. Low Total Harmonic Distortion(THD)
7. Large input voltage range of 3V-18V. 
8. Very low no load current.
9. Frequency Response 20Hz-20KHz.

Pin Configuration :

Very easy pin configuration. From the configuration you can see it works as a bridge amplifier.

Now lets see the diagram!

Circuit Diagram :

This diagram is very easy to understand. The pin 2 is used for the input of audio signal, 4.7Kohm variable resistor is used for controlling volume. A speaker is directly connected with the output. This circuit can be built on a small but good quality PCB. The capacitors with the voltage input section are for filtering. For battery operation these are not mandatory. The gain of this IC is internally fixed at 40dB.

As this circuit is designed to work with low voltage input it uses Bridge Tied Load Principle (BTL) provide around 1 or 2 Watt output power. 

Uses :

1. Small portable devices which is battery fed.

Notes :

To view the datasheet click here.

To read my other posts, click here.

Friday, March 28, 2014

Fluorescent Lamp from 12V

Good evening everyone. Hope you guys are doing great! So many of us have seen a fluorescent lamp driver in action, from a battery. This is a very common thing in car or emergency lamps.

Now lets see how easily a circuit can be made to serve this purpose. First take a look at the diagram then!

Fluorescent Lamp From 12V

This diagram will be a very easy one. In the heart of this circuit there is a 555 timer IC that is in an astable multi-vibrator mode. It provides the necessary oscillation frequency to be delivered to the transformer, as we all know transformer does not work in DC so we have to provide AC for this. The output of the 555 IC is very small so we have to amplify it. The MOSFET will do the job of amplifying.

Note : 

1. T1 or the Transformer one can be a small transformer that has a 220V winding and a 12V Winding. Make sure to connect the 220V side to the LAMP and 12 V side to the circuit. In this particular circuit it will work as a step up transformer.
2. The high voltage side of the transformer will provide very high voltage so you might get shock, do not touch the circuit while it is running. 
3. The 0.01uF capacitor with the LAMP must be rated at at-least 1KV.
4. It is better to use an electrolytic capacitor with the pin 2 of the IC.
5. MOSFET IRF510 might get hot, so attach a heat-sink with it.
6. 12V Lead acid/Sealed Lead Acid battery or 12V DC source( Maybe an adapter) can be used. 
7. A lamp of 4W/6W can be used with this circuit.
8. Just connect the two opposite pins of a LAMP ( even if it has 4 pins, 2 in each side).

Good Luck!

To Read my other posts, click here.
Another post about 555 IC, click here.

Fun With LM386

Good evening everyone. Hope you guys are having a great time. Now that my system is on a boot time virus scanning process and it will take a long time I guess I can write something on a small amplifier that can be used in many different places like intercom, small amplifier for MP3 player or radio or maybe any similar application.

So this post is about a small amplifier and I am going to use the great LM386 chip for this. So let’s take a look at the IC first and then I will show a few circuit diagrams.

From the diagram you can see it has a pretty straight forward pin out. Just hook up a power supply, give it some input signal and it will provide output. Diagrams are also very easy.  Gain of this IC is internally set to 20 but you can change it to 200 just by adding an extra component. One of the major benefits of this is IC is it requires only a few external component to work.


1. Only a few external components,

2. Operating voltage range is 4V-15V so it can be operated by battery,

3. At no load it draws only 4mA of current (it can be left turned on for long time),

4. It features low distortion.

So first let’s look at a diagram of small audio amplifier.

As you can see in the figure that the diagram is fairly simple. The input 10Kohm variable resistor works as a volume controller. Pin 3 is the non-inverting input, we will input the signal here, pin 2 which is the inverting input, we will just hook it up to the ground directly ( If you have idea on op-amp you should know this). The output is taken from the pin 5 of this IC and we will use either an 8ohm speaker or 16ohm speaker.

Switch 1 is used for controlling the gain, the options are either 20, 50 or 200. A three way selector switch can be used.

When switch 1 is connected through the 10uF capacitor it will give a gain of 200. When it is connected through the 10uf capacitor in series with the 1.2Kohm resistor it will give a gain of 50. And when it will float free it will give a gain of 20.

Switch 2 is used for turning on/off the bass booster.

Bypass capacitor with the pin 7 can be anything from 47uF to 100uF of proper voltage.

Now let’s look at another figure, it can be used in intercom or something similar.

In this figure as you can see the input is taken from a microphone. 22uF capacitor at the input blocks the DC. Same as before 10kohm variable resistor is used for controlling the volume.

Gain controller and bypass capacitor of this circuit is same as before.

As this circuit is targeted for vocal type range so we don’t need a bass booster on this.

The switch 1 here is of press and hold type, you have to press and hold the button to keep the circuit running.  It is because we don’t want to run the circuit all the time.

So that was all about the small amplifier with LM386 IC.


1. If you want to learn more about this circuit you can take a look at its datasheet here.

2. Use capacitors with voltage rating a bit higher than the supply voltage.

3. High quality images uploaded, open in new tab to see the full sized image.
4. LM386 can deliver up to 1W.

As this circuit consumes a small amount of current you can easily use a 9V 6F22 battery with it.

Hope you have enjoyed reading this post and I guess now you can make it by yourself. Happy experimenting.

To read my other posts, see the index.

To see a power supply diagram for this one click here.

Thursday, March 27, 2014

Installing Windows From USB Drive

Good afternoon and hope everyone is in good health and spirit. As you might already know that optical disks have become less popular this days and often times people don't even have an optical disk drive in their system.  So what can you do if you want to install an fresh copy of windows in your system? Well that's what I'm going to show you now.

What we will need?

1. An 8GB(or more) Flash drive
2. A licensed copy of Windows (Normal Or .ISO file)
3. Around 30 minutes for making boot-able drive and 30 minutes for installation.(might take much less with faster drives)
4. Windows 7 USB DVD Tool. (Free and only needed for easy method)

How to make it boot-able :

 I have two options for you, both of them are easy the second one is arguably easier.

Method 1 : The Geeky method!
Method 2 : The Easy method!

First the method 1, the geeky method! 

1. Hook up your USB drive into any of the USB ports of a system that is running a Windows 7/8/8.1/10 32/64bit. Make sure the USB Drive is empty or transfer all your necessary information out of it.

2. First step we will need disk partition manager but for this method first we will need to launch the Command Prompt. You can type CMD in the start menu to locate it. Make sure to click on the Run As Administrator.

In windows 7.

In Windows 8.1.

From the command prompt launch Disk partition manager by typing Diskpart and hitting enter.

3. Now Type List Disk to get the list of connected disks.

Now this might look different in your system depending how many drives are connected. In my system Disk 3 is an 8GB USB drive as you can see from the size.

4. Now we will select the proper USB Drive. To do this type Select Disk #
# stands for numeric digit, which will represent the proper USB drive.


5. To remove existing hidden sectors and partition type Clean and hit enter.

6. After cleaning type Create Partition Primary to create partition with default parameters.

7. To focus on the newly created partition type Select Partition 1 and hit enter.

8. To set the partition in focus in active just type in Active and hit enter.

9. Now to format this partition with NTFS just type Format FS=NTFS and hit enter. FS stands for file system. ( This process might take a good amount of time, be patient)

10. Now you will need to assign a new drive letter, just type Assign and hit enter.

As you can see a new drive letter O is assigned.

11. After Assigning New Drive letter just hit exit to exit from Disk Partition.

Now for the next step we will have to make the pen drive boot-able.

12. I'm going to make this process a bit easier.All you need to do is just go to your the directory where you have kept your installer files and  locate the folder Boot. Enter in there and you will see a file named bootsect.exe (.exe might not show depending on your configuration). It looks like this

12. Now take a look at your command prompt and see the directory name.

Which is in my case C:\Windows\System32

Now copy that Bootsect.exe file from your windows installation media and paste it in here.

13. Now get back to the command prompt and type in Bootsect.exe /nt60 O: ( Remember it might not be drive O for you.)

Command prompt will let you know if its successful or not. As you can see here it has succeeded in making the drive boot-able. You can exit the command prompt now.

14. One last thing copy everything from the windows installation media to this boot-able USB Drive.

and you are good to go!


1. You could have just used the command prompt to reach the folder too but copying one single file is pretty simple so I have used that method.

2. It is better to have the normal installation files rather than the .ISO file as windows 7 won't mount them by it's own, you need some sort of applications that can mount .ISO files.

Now method 2, the easy method

1. Go to this link and download Windows 7 USB/DVD Tool.
Don't worry about the virus, It is completely safe.

2. Just install the software and Launch it.

3. Now in the first step you will have to select the ISO. So select the ISO file of windows.

4. Simply Click next. Now you will see multiple options like whether it will be copied on a USB or DVD. Just click the USB Device

5. Now select proper USB device and begin copying. If it wants to erase everything let it erase.

And you are done!

In this method however it is better to have the .ISO file as it works with this type of file only. If you have the normal installation files you might need an application that can make .ISO files.

Now safely remove the USB drive and hook it up to the system in which you want to install this operating system. Start the machine and boot from this USB device.

(  After turning on your system you will have to enter into the UEFI/BIOS to change the boot device to USB device, or you can press function key to directly boot from USB, in gigabyte board it is F12, It is also F12 for the test Toshiba Laptop I have in my hand)

Once you have selected the device you will be able to install windows from this device.

Some Spacial Notes:

A. If you can't boot from your USB, check the couple things.

1. Usually it is better to use the USB2.0 port as often times slightly older models might not have proper driver for USB3.0 on the boot menu. For newer system however you might have to do the opposite.

2. Sometimes in modern systems you might have to turn on Legacy Boot to boot from such devices.

B. If you have a USB drive of certain size and it is showing much less than that.

Say if you have a USB drive that has a capacity of 16GB and all you can use is like 100MB then chances are that space is there but on a different partition which it won't show. To get rid of this problem just follow the Step 1 to 10 of the Geeky method and it should work.

So that is pretty much it! Hope it has helped and Good luck.