# Current Amplification w/ ICL8038 & LM741: Can I Get 1A?

• Habeebe
In summary, you will need an op-amp that can output 1A or higher to use the current amplification circuit found in a book. If you are running on a 12V power supply, then the load impedance must be 12 ohms or lower.
Habeebe

## Homework Statement

I had a circuit in lab using an ICL8038 function generator IC, and was using the sine wave output from the chip. I am being asked to add components to increase available current to 1A. The chip pulls a steady 13mA, but I derped and didn't check output current. The spec sheet for the chip says that they had 5mA output for an impedance of 200 ohms.

So, I figure I'm looking for a current gain around 1A/5mA=200. I grabbed a op-amp current-to-current amplification circuit out of a book in the lab that is as such:

Where gain=1+Rf/Rs

So I choose something like Rf=200kΩ and Rs=1kΩ or some such configuration with the same ratio. Is this correct?

If it is correct, this only works in the case that the op-amp can push that much current. If I'm running something that I can find in lab, like an LM741 at 12V, how do I know how much current gain I can get? I checked the spec sheet on it, but it doesn't have anything about current limitations. If 1 op-amp won't do it, can I just stick another identical circuit into the spot where the load resistor is?

Thanks.

Given above.

Given above.

Habeebe said:

## Homework Statement

I had a circuit in lab using an ICL8038 function generator IC, and was using the sine wave output from the chip. I am being asked to add components to increase available current to 1A. The chip pulls a steady 13mA, but I derped and didn't check output current. The spec sheet for the chip says that they had 5mA output for an impedance of 200 ohms.

So, I figure I'm looking for a current gain around 1A/5mA=200. I grabbed a op-amp current-to-current amplification circuit out of a book in the lab that is as such:

Where gain=1+Rf/Rs

So I choose something like Rf=200kΩ and Rs=1kΩ or some such configuration with the same ratio. Is this correct?

If it is correct, this only works in the case that the op-amp can push that much current. If I'm running something that I can find in lab, like an LM741 at 12V, how do I know how much current gain I can get? I checked the spec sheet on it, but it doesn't have anything about current limitations. If 1 op-amp won't do it, can I just stick another identical circuit into the spot where the load resistor is?

Thanks.

Given above.

## The Attempt at a Solution

Given above.

Sounds like a good lab.

A couple hints... You probably will not find an opamp that can output 1A. Opamps are for lower current signal processing chores. To get higher current output, you will usually use either discrete transistors, or something like an audio amp IC. Try doing some Google searching on those two options (use Google Images to speed up your searching), and see what you find. Post your follow-up questions here in this thread with your search results...

But I can find transistors that'll handle >1A, so I can just use a Darlington pair, right? ...but, if I'm running on a 12V power supply, then to get my 1A, my load impedance can only be 12 ohms max. This answers the question for my lab, but out of curiosity, if I wanted to run a higher impedance load, could I chain together more Darlington pairs? Could I increase the current through the load by setting the voltage across the collector and emitter to +12V -> -12V instead of +12V -> ground?

Last edited:

## 1. What is the purpose of using ICL8038 and LM741 in current amplification?

The ICL8038 is a precision waveform generator chip that can output a sine, square, or triangle wave with adjustable frequency. The LM741 is an operational amplifier that can be used to amplify electrical signals. When used together, they can create a current amplification circuit.

## 2. Can I use ICL8038 and LM741 to achieve a current amplification of 1A?

No, the ICL8038 and LM741 are not designed to handle such high currents. The maximum output current of the ICL8038 is 20mA and the LM741 is around 40mA. Attempting to achieve a current amplification of 1A with these chips can damage them.

## 3. How do I calculate the current amplification achieved with ICL8038 and LM741?

The current amplification of a circuit is determined by the ratio of the output current to the input current. To calculate this, you will need to measure the input and output currents of your specific circuit using a multimeter and then divide the output current by the input current.

## 4. Are there any safety precautions I should take when working with ICL8038 and LM741 for current amplification?

Yes, it is important to always follow proper safety protocols when working with any electronic components. Make sure to use appropriate protective gear, such as gloves and safety glasses, and work with the circuit only when it is turned off and disconnected from power sources.

## 5. Can I use ICL8038 and LM741 for other types of amplification besides current amplification?

Yes, both chips have a wide range of applications and can be used for voltage amplification, signal conditioning, and more. It is important to carefully study their specifications and characteristics to determine if they are suitable for your specific needs.

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