9/17/2023 0 Comments Analog opto isolatorI did not want the wandering common mode of these signals to interfere with my main communication channels, which travel along these cables and are unshielded.I just went with standard RS-422 Rx/Tx differential pairs driving a medical-certified AduM2286 magnetic isolation IC and a couple of (over-dimensioned) supplies. The transmitting side seems more problematic as any solution I can think of would imply a reduced signal level that would then require a level shifter or comparator on the other side (such as this one) which would then require a few more components to function and to add proper ESD protection.Īm I over-complicating this? Should I just byte the bullet and add the wasteful power supply and a couple of RS-422 transceivers at each end? Simulate this circuit – Schematic created using CircuitLab The receiving side seems simple enough as it would be a relatively high-current signal driving the optocoupler LED (and a balancing diode) that can use a 100Ω resistor on each end of the line. I would like to get away with just "passive" optocouplers and a minimum of additional circuitry on the data acquisition equipment side, but I am concerned with proper termination of the 100Ω differential pair. On the isolated side of the box I only have access to 48V DC, and would like to avoid adding another over-specified switching power supply just to power the digital interface (I already need one for the non-isolated side). The overall cable length that the digital signals (short pulses >10µs) will travel is 10m or less, but edge integrity is critical. The purpose of this box is to inject power and to provide communications and digital signal isolation. If you do not allow these cookies, you will experience reduced relevant content.I am designing a dumb "isolation box" that is to sit between a computer and medical data acquisition equipment. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. They may be used by Analog Devices to build a profile of your interests and show you relevant content on our site. Targeting Cookies: These cookies may be set through our site by Analog Devices and our service providers. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance. All information these cookies collect is aggregated and therefore anonymous. They help us to know which pages are the most and least popular and see how visitors move around the site. Performance Cookies: These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. If you do not allow these cookies then some or all of these services may not function properly. They may be set by us or by third party providers whose services we have added to our pages. Functional Cookies: These cookies enable the website to provide enhanced functionality and personalization. These cookies do not store any personally identifiable information. You can set your browser to block or alert you about these cookies, but some parts of the site will not then work. They are usually only set in response to actions made by you which amount to a request for services, such as setting your privacy preferences, logging in or filling in forms. Strictly Necessary Cookies: (Always Active) These cookies are necessary for the website to function and cannot be switched off in our systems. After we finish updating our website, you will be able to set your cookie preferences. Analog Devices is in the process of updating our website.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |