I bought a switching power supply that outputs +12.5V. How can I get a +12V1A low-ripple voltage output?

guazhuaq

I bought a switching power supply that outputs +12.5V. How can I get a +12V1A low-ripple voltage output? [Copy link]

Is there an LDO chip that can be used directly? Or should I first boost the voltage and then use an LDO chip to step down the output voltage?

maychang

If the ripple of the switching power supply you bought is acceptable and you only need to reduce the output DC voltage by 0.5V, you only need to fine-tune the voltage divider resistors at the output of the switching power supply (the two resistors are used for feedback) to make the output reach an accurate 12V. If the ripple is too large, it is recommended to add a level of LC filtering.

qwqwqw2088

After all, LDO is a linear regulator, which can only step down the voltage. Generally, the input and output can be realized according to the circuit recommended in the data sheet.

chunyang

How much ripple is needed? What is the ripple of the current 12.5V power supply? First confirm the demand, then examine the supply. If the indicators are not much different, the best way is to modify the switching power supply, as Maychang said on the second floor. LDO usually outputs 5V or less. I don’t know if there is an LDO that meets the requirements of the original poster. It is estimated that even if there is, it is likely to be difficult to buy or the price is high. Of course, you can build it yourself using discrete components, and only PNP tubes can be used for adjustment tubes. However, this method is still costly. It is better to directly consider purchasing a switching power supply that meets the requirements or increase the voltage and then use secondary voltage stabilization to obtain a power supply that meets the requirements.