Hi all,
I have a TLC271 and I want to boost a 5V signal to 12V. I have a 12V source (stretched but it will do), but I'm struggling to understand how to connect the IC. The datasheet is to tech for me...
I imagine the TLC271 may not be the best choice, but it will have to do for now.
Can you help me understand how to connect the pins?
Currently I have:

• IN- to GND
• GND to GND
• IN+ is my 5V signal
• VDD to 12V

But I don't know about Bias, Offset 1 and Offset 2...
Thanks!

 

I presume you already have TLC271 chips on hand. I am curious as to why you chose this IC.
There is nothing wrong with this IC and there are many other op amps like it.

The first thing you need is the manufacturer's datasheet. You need to know the pinout of this IC. More importantly, you need to become accustomed to reading device specifications, as complicated as it may seem. Very often, the datasheet will show device test circuits and even application examples.

Now, an op amp is a generic "black box" component. You need to look up some electronic sites to learn different ways one can configure an op amp. Here are two examples:

https://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/introduction-operational-amplifiers/

https://www.electronics-tutorials.ws/opamp/opamp_8.html

To cut to the chase, you need a non-inverting op amp circuit configuration.



The voltage gain of this circuit is R2 / R1.

 

I presume you already have TLC271 chips on hand. I am curious as to why you chose this IC.
There is nothing wrong with this IC and there are many other op amps like it.

The first thing you need is the manufacturer's datasheet. You need to know the pinout of this IC. More importantly, you need to become accustomed to reading device specifications, as complicated as it may seem. Very often, the datasheet will show device test circuits and even application examples.

Now, an op amp is a generic "black box" component. You need to look up some electronic sites to learn different ways one can configure an op amp. Here are two examples:

https://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/introduction-operational-amplifiers/

https://www.electronics-tutorials.ws/opamp/opamp_8.html

To cut to the chase, you need a non-inverting op amp circuit configuration.

View attachment 330418

The voltage gain of this circuit is R2 / R1.

Thanks, this helps, getting there.
This is the schematic and I can't really figure out what to do with the 2 offsets and bias...


I picked this IC because I found it in an example somewhere.
I also need to be able to read what the right "direction" of the chip is as I smoked a couple of them cause they were rotated...

Finally, could you suggest something more appropriate?
I have 5V DC outputs and I need to power 12V led strips. No dimming, just on/off.
Thanks!

 

You might be on the wrong track here...an Op-Amp cannot boost voltage.

If you are using the 5-volts as a signal and a proper 12-volt supply to power the LEDs then you just need a transistor.

 

Is the 5V a variable voltage or just on/off?

 

Is the 5V a variable voltage or just on/off?

Just on/off

 

If you have a 5 V power source you cannot use an op amp to supply 12 V LEDs.
What you need is called a boost DC-to-DC converter or step up DC-to-DC converter.
Something like this:

https://www.amazon.co.uk/Step-Up-Module-Converter-2-6-5-5-ND0412SA/dp/B0C81SSGKL/

 

If you have a 5 V power source you cannot use an op amp to supply 12 V LEDs.
What you need is called a boost DC-to-DC converter or step up DC-to-DC converter.
Something like this:

https://www.amazon.co.uk/Step-Up-Module-Converter-2-6-5-5-ND0412SA/dp/B0C81SSGKL/

I have both, and I have 42 separate leds to control. That's why I was using this opamp, but is there anything "smarter"?

 

If you have a 12V source as you stated, then you just need a transistor as a switch to control that voltage to the LEDs.

 

If you have a 12V source as you stated, then you just need a transistor as a switch to control that voltage to the LEDs.

Can I control a transistor with a 5V though? If the output is 12V? I was told the gate control must be at least the output voltage, can't be smaller

 

You can control a BJT transistor on and off with just 1 V signal, even if the supply voltage is 5 V or 12 V.
If the transistor is MOSFET, then the control voltage must be at least 3 V.

 

You can control a transistor on and off with just 1 V signal, even if the supply voltage is 5 V or 12 V.

oh! Could you suggest a model/PN... anything? Thanks!

 

oh! Could you suggest a model/PN... anything? Thanks!

How much current do you need to supply?
2N3904 can handle 200 mA
2N2222 can handle 600 mA
TIP31 can handle 3 A

and there are thousands of others available.

 

How much current do you need to supply?
2N3904 can handle 200 mA
2N2222 can handle 600 mA
TIP31 can handle 3 A

and there are thousands of others available.

Max 60mA each, thanks! That's a good starting point!

 

This is your basic LED controller using an NPN BJT such as 2N3904.



If your LED forward voltage is 2 V and draws 16 mA, then the series resistor R1 is calculated from

R = (Vs - Vf)/ Id

Where,
Vs = supply voltage
Vf = LED forward voltage
Id = LED current

R1 = (5V - 2V)/ 16mA = 188 Ω

Any value from 220 Ω to 1 kΩ will work, with dimmer output at higher resistance values.

R2 can be anything from 100 Ω to 5 kΩ.

 

This is your basic LED controller using an NPN BJT such as 2N3904.

View attachment 330439

If your LED forward voltage is 2 V and draws 16 mA, then the series resistor R1 is calculated from

R = (Vs - Vf)/ Id

Where,
Vs = supply voltage
Vf = LED forward voltage
Id = LED current

R1 = (5V - 2V)/ 16mA = 188 Ω

Any value from 220 Ω to 1 kΩ will work, with dimmer output at higher resistance values.

R2 can be anything from 100 Ω to 5 kΩ.

How can I rearrange this circuit if the LEDs are already all wired as Common Cathode?

 

It is late in the game to be introducing new information.

Do you want to switch the LEDs on and off individually?

Are all of your LEDs already connected in a common cathode configuration?

What is the source and voltage range of the control signal?

 

Please post exactly how the LED array is connected.
Can you post the “example” you found?

 

Here is a word of advice when posting questions on AAC.

You began by requesting information on how to use an op amp to convert 5 V to 12 V.
Now we can see that the final goal has nothing to do with the problem stated. In order to avoid playing the game of 101 Q & A, it is better for everyone if you start off with the actual problem and not what you envision is your problem.

We see this too often here on AAC forums and strive to make the AAC experience more efficient and enjoyable for everyone concerned.

 

if you start off with the actual problem and not what you envision is your problem.

Also not stating what you think the solution is if you are unfamiliar with electronics.