UC1843: Boost converter design

Johnson John

Part Number: UC1843

Hello,

Can you please clarify whether this chip (UC1843) can be used for Boost converter to meet the following requirements?

Vin range : +20VDC to +140VDC

Vout Output voltage : +70VDC

Output current : 0.9A

We want to pass through the Vin when the input voltage goes above the Vout.

thank you,

Johnson John

0 Hong Huang over 2 years ago

Hi,

UC1843 can be used for boost converter.

It looks your specs are more like buck-boost, or sepic. Either, UC1843 is ok to use.

0 Johnson John over 2 years ago in reply to Hong Huang

Hi Hong Huang,

thank you for the prompt response.

I want to use this chip in boost configuration (without isolation) using inductor, Is it fine?

Can this chip pass through the Vin to Vout when Vin >Vout?

thank you,

Johnson John

0 Hong Huang over 2 years ago in reply to Johnson John

Hi,

When Vin > Vo, the IC will stop the pulses. Then the Vin will connect to Vout through the boost diode.

0 Johnson John over 2 years ago in reply to Hong Huang

thank you, Hong Huang,

Could you please confirm, when Vin changes to greater than Vout and then Vin changes back to less than Vout, Will the chip start regulating?

Do you have Ltspice model for this chip?

0 Hong Huang over 2 years ago in reply to Johnson John

Hi,

Yes, the chip will back to regulate the Vout.

No, we do not support LTspice.

Power management forum