foges
Newbie level 2
Hello people,
I'm designing an ECG circuit with a digital output that is supposed to be hooked up to an FPGA board, but I have a bit of a problem. My circuit operates at 5V, whilst the FPGA only operates at 2.5V and I also want to galvanically isolate the two. I initially thought I might be able to get an optocoupler to do the job, but it seems there are no optocouplers that will operate with a supply of less than 2.7V. One option would to be to use some sort of a voltage converter (probably switched capacitor) from 2.5V to 2.7V, but this just seems awfully complicated. Anyone have any better advice on other components that might do the job?
Oh, yeah I am using an SPI interface, so I'm going to need something that is bi-directional and has three channels..
I'm designing an ECG circuit with a digital output that is supposed to be hooked up to an FPGA board, but I have a bit of a problem. My circuit operates at 5V, whilst the FPGA only operates at 2.5V and I also want to galvanically isolate the two. I initially thought I might be able to get an optocoupler to do the job, but it seems there are no optocouplers that will operate with a supply of less than 2.7V. One option would to be to use some sort of a voltage converter (probably switched capacitor) from 2.5V to 2.7V, but this just seems awfully complicated. Anyone have any better advice on other components that might do the job?
Oh, yeah I am using an SPI interface, so I'm going to need something that is bi-directional and has three channels..
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