Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

12Vin to 24Vout (<1W) DCDC modules do not exist with Vout accuracy better then +/-5% ?

Status
Not open for further replies.
We are using 10 ADG1438 multiplexors and feeding them 24V to VDD and -5V to VSS.
Abs Max for VDD is 25V.


The total current draw will be <10mA for all ten of them.
Our power source is 12V…..As such, we are trying to find a 12Vin to 24Vout, <1W DCDC module.

However, every single one I find on the web has a poor load regulation of 10%. This means it could blow up our ADG1438’s.

As such , we are wondering if we are going to need a discrete MC33063A based boost converter. The software engineers prefer a simple DCDC module but it looks like I must tell them that no suitable DCDC modules exist?

ADG1438 datasheet
https://www.analog.com/media/en/technical-documentation/data-sheets/ADG1438_1439.pdf

MC33063A datasheet
https://www.ti.com/lit/ds/symlink/m...https%3A%2F%2Fwww.ti.com%2Fproduct%2FMC33063A
 
For good reliability I would operate a device at no more than 90% of its Max rating.
Do you have a 24V signal going to the mux?
 
I just looked up TI's MC33063A which has a 2% voltage reference. This is a very old part. I think newer parts are better.
From data sheet. Line regulation = 0.12% Load regulation (10% to 100%) = 0.09%
It is true some parts do not do well on load regulation at zero current. You might need to add a resistor on the output to give it some minimum load.

Multiplexors are not good if there is high frequency noise on the power supply. You might want to add a LC filter on the 24 volt line to clean it up.
 
One way of handling poor regulation from your primary supply is to set it's output a couple of volts high. Then follow it with a low dropout linear regulator.

The LDO post regulator will also give you good noise filtering.
 
Do you have a 24V signal going to the mux?
Thanks, i believe we will be able to keep it below 24V......just

Multiplexors are not good if there is high frequency noise on the power supply. You might want to add a LC filter on the 24 volt line to clean it up.

We have about 5uF of capacitance on the 24V output...but its on virtually no load, so i believe there will be little high frequency ripple voltage on the Vout, if thats what you were referring to.
PQDE6W-Q110-S24
...thanks, but this one cant do our 12vin.
 
Oops. Sorry, wrong part number.

Screenshot_20201119-102832_Drive.jpg
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top