Looking for a linear voltage regulator chip

sky999

Looking for a linear voltage regulator chip [Copy link]

I often use 24V to 5V or 12V to 5V, and the current does not exceed 5V500MA. Is there any chip that can directly convert 24V to 5V linear voltage regulator?

qwqwqw2088

24V to 5V does not necessarily require linear step-down

You can use the switch chip LM2596S-5.0

sky999

qwqwqw2088 posted on 2019-8-22 16:48 24V to 5V does not necessarily require linear step-down. You can use the switch chip LM2596S-5.0

Well, I know this. I mostly use ADC, so I need a linear power supply. Usually I use 2596ADJ to convert 9V, and then use 7805 to output 5V, but I think the circuit is a bit troublesome, and I only use 500MA of the 3A current of 2596, which always feels wasteful.

qwqwqw2088

sky999 posted on 2019-8-22 16:56 Well, I know this. I mostly use ADC, so I need a linear power supply. Generally, 2596ADJ is converted to 9V, and then 7805 is used to output 5V, but I think...

If the ADC is powered, you can use two-stage voltage reduction, and use LDO to 5V in the last stage.

For example, 1117 or ME6117

sysjtlwx

This power supply selection guide has the chips you need. After a quick look, there are probably 3-5 models that meet your requirements.

maychang

24V drops to 5V, the current is 500mA, and the loss on the chip is 0.5A (24V-5V) = 9.5W, which is too large and requires a large heat sink.

sky999

maychang posted on 2019-8-22 17:51 24V drops to 5V, the current is 500mA, and the loss on the chip is 0.5A (24V-5V) = 9.5W, which is too large and requires a large heat sink.

Um, this is a difficult question. Is there any chip circuit that is simpler than 2596 DCDC? I want to reduce it to 7~9V first and then use 7805 or 1117

sky999

sysjtlwx posted on 2019-8-22 17:14 This power supply selection guide has the chip you need. After a quick look, there are probably 3-5 models that meet your requirements.

Thanks, let's see!

maychang

sky999 posted on 2019-8-23 09:34 Well, this is a difficult question. Is there any chip circuit that is simpler than 2596 DCDC? I want to reduce it to 7~9V first and then use 7805 or 1117

"I want to reduce the voltage to 7~9V before using 7805 or 1117"

This is a good idea. It’s what most people do when they encounter a situation like yours.

maychang

sky999 posted on 2019-8-23 09:34 Well, this is a difficult question. Is there any chip circuit that is simpler than 2596 DCDC? I want to reduce it to 7~9V first and then use 7805 or 1117

"Is there any DCDC chip circuit simpler than 2596?"

I'm afraid it's hard to find.