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Left closed in review as "Original close reason(s) were not resolved" by Velvet, Voltage Spike♦
Post Closed as "Needs details or clarity" by Andy aka, ocrdu, Simon B
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ocrdu
ocrdu
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Buck-converter converter adjustable output-voltage using digital-potentiometer potentiometer

I am trying to design a buck converter using LM2576HVan LM2576HV (Vref:1 1.23 V) and a digital potentiometer. (Inputinput:48 48 V, Outputoutput: 0 to 48 V, Imax=3Imax= 3 A).

But theThe digital potentiometer with the highest supply voltage I could find works with 36 V. So I can only get 1.23-36 V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101a TPS7A4101 that converts 48 V to 36 V to be able to supply the potentiometer, then using an opampop-amp to be able to increase the digital potentiometer output from 36 to 48 V. In this way, the output will be 1.65-48 V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opampop-amp output. 

Also I can't get 0 V at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0 V?

Buck-converter adjustable output-voltage using digital-potentiometer

I am trying to design a buck converter using LM2576HV (Vref:1.23 V) and a digital potentiometer. (Input:48 V, Output: 0 to 48 V, Imax=3 A).

But the digital potentiometer with the highest supply voltage I could find works with 36 V. So I can only get 1.23-36 V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101 that converts 48 V to 36 V to be able to supply the potentiometer, then using an opamp to be able to increase the digital potentiometer output from 36 to 48 V. In this way, the output will be 1.65-48 V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opamp output. Also I can't get 0 V at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0 V?

Buck converter adjustable output-voltage using digital potentiometer

I am trying to design a buck converter using an LM2576HV (Vref: 1.23 V) and a digital potentiometer (input: 48 V, output: 0 to 48 V, Imax= 3 A).

The digital potentiometer with the highest supply voltage I could find works with 36 V. So I can only get 1.23-36 V at the output of the buck converter.

I am thinking of using a linear regulator like a TPS7A4101 that converts 48 V to 36 V to be able to supply the potentiometer, then using an op-amp to be able to increase the digital potentiometer output from 36 to 48 V. In this way, the output will be 1.65-48 V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the op-amp output. 

Also I can't get 0 V at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0 V?

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winny
winny
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I am trying to design a buck converter using LM2576HV (Vref:1.23V23 V) and a digital potentiometer. (Input:48V48 V, Output: 0 to 48V48 V, Imax=3AImax=3 A).

But the digital potentiometer with the highest supply voltage I could find works with 36V36 V. So I can only get 1.23-36V36 V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101 that converts 48 voltsV to 36 voltsV to be able to supply the potentiometer, then using an opamp to be able to increase the digital potentiometer output from 36 to 48 voltsV. In this way, the output will be 1.65-48V48 V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opamp output. Also I can't get 0 voltsV at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0V 0 V?

I am trying to design a buck converter using LM2576HV (Vref:1.23V) and a digital potentiometer. (Input:48V, Output: 0 to 48V, Imax=3A).

But the digital potentiometer with the highest supply voltage I could find works with 36V. So I can only get 1.23-36V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101 that converts 48 volts to 36 volts to be able to supply the potentiometer, then using an opamp to be able to increase the digital potentiometer output from 36 to 48 volts. In this way, the output will be 1.65-48V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opamp output. Also I can't get 0 volts at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0V ?

I am trying to design a buck converter using LM2576HV (Vref:1.23 V) and a digital potentiometer. (Input:48 V, Output: 0 to 48 V, Imax=3 A).

But the digital potentiometer with the highest supply voltage I could find works with 36 V. So I can only get 1.23-36 V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101 that converts 48 V to 36 V to be able to supply the potentiometer, then using an opamp to be able to increase the digital potentiometer output from 36 to 48 V. In this way, the output will be 1.65-48 V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opamp output. Also I can't get 0 V at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0 V?

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Deniz Kılıç
Deniz Kılıç
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Buck-converter adjustable output-voltage using digital-potentiometer

I am trying to design a buck converter using LM2576HV (Vref:1.23V) and a digital potentiometer. (Input:48V, Output: 0 to 48V, Imax=3A).

But the digital potentiometer with the highest supply voltage I could find works with 36V. So I can only get 1.23-36V at the output of the buck converter.

I am thinking of using a linear regulator like TPS7A4101 that converts 48 volts to 36 volts to be able to supply the potentiometer, then using an opamp to be able to increase the digital potentiometer output from 36 to 48 volts. In this way, the output will be 1.65-48V.

Would this be the right approach or should I go a different way? I have doubts about whether I can get enough current from the opamp output. Also I can't get 0 volts at the output because of the reference voltage of the LM2576HV. How can I reduce the minimum voltage at the output from 1.65 to 0V ?