Help needed to select a high side switching solusion - Page 1
Forum section: electronics / projects

author: onelectron
author_rank: Newbie
timestamp: July 13, 2022, 12:41:33 pm
content: I need a high-side switching solution. From the diagram, you can see that there are two different sources. One with a voltage range of 12 to 24V and the other one is a 24 to 50V source. And the third element is a resistive load. I need a semiconductor-based SPDT switching solution (or something else) that will allow the terminal "A" to be connected and disconnected from and to terminals "B" and "C" at a high frequency. I am working on something where I need to boost or bias the 12-24V source "A" with 24-50V source "B" to perform a certain operation. The switching frequency can be from 10 Hz to 1 KHz. The higher the switching frequency, the better. Any suggestions?

author: ledtester
author_rank: Super Contributor
timestamp: July 13, 2022, 01:23:12 pm
content: Quote from: onelectron on July 13, 2022, 12:41:33 pmYour schematic would put the power supplies in parallel when A is connected to B. Is this what you're looking for?

author: onelectron
author_rank: Newbie
timestamp: July 13, 2022, 02:03:59 pm
content: Yes. For an experiment, I need to connect both the sources for a short period of time and then need to connect the 12-24V source to the load after that. The 24-50V load will only get connected to the 12-24V source momentarily, but will never get connected to the load. I have found this relay. Will it work?https://www.digikey.de/en/products/detail/omron-electronics-inc-emc-div/G6K-2F-RF-DC5/503107

author: Doctorandus_P
author_rank: Super Contributor
timestamp: July 13, 2022, 02:31:25 pm
content: That omron thing is an electro mechanical relay.It can switch signals upto 1GHz, but it does not switch particularly fast (3ms to turn on or off).Your best bet is probably two MOSfets and then add some more circuitry to switch them at the right time.Maybe you can use "optomos" relays, but there is not enough information in your post. How much current do you need to switch for example?

author: onelectron
author_rank: Newbie
timestamp: July 13, 2022, 02:41:44 pm
content: Thanks for your reply. i'll switch maximum 1 amp current.I also have found another beand. this relay can also switch DC signals:https://menlomicro.com/images/general/Menlo_MM1200_Preliminary_Datasheet_Rev1.2.pdfhttps://menlomicro.com/images/general/Menlo_MM3100_Preliminary_Datasheet_Rev1.2.pdfbut not sure if they will work or not.

author: ledtester
author_rank: Super Contributor
timestamp: July 13, 2022, 02:48:24 pm
content: You want a switching frequency of 1 KHz. The MM1200/3100 micro relays are guaranteed for around 3 billion switching operations. Will that be enough?

author: onelectron
author_rank: Newbie
timestamp: July 13, 2022, 02:59:42 pm
content: I mean, obviously the switching speed of these devices is more than enough, but in most of the cases when I looked for a MEMS switch, they were actually MOSFET based analog switches, and in this case, if these devices work exactly like an electro-mechanical relay, then it will perfectly work for my particular purpose. But I am not sure if they work based on the working principle of the electro-mechanical relay.