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GCA_OK1 Isolated input buffer cq level shifter for 3.3/5V solutions


By Peter Giling, Copyright GCA


In the past, all buffer boards for input and output, for the different interfaces
were desinged for a 5V level. But slowly, more and more units will work with 3.3V.
In general, but with a few exceptions, most output drivers will not have any problem with that.
Mostly the match can be done by changing resistors or resistor arrays, if necessary.
With input buffers, mostly sensor boards, various anwanted situations can occur.
These boards need a supply of 5V, and send out a 5V level, which some units will have problems with.
There are levelshifters available to convert between 3.3V and 5V, but they are not always useable.
The reason for that is the level-shifter itself.
That is where this unit comes on handy, specificly because opto-coulers are used.

The input side of this board needs 5V supply to be sure that the sensor interface is correcly supplied.
The input signal passes an opto-coupler which separates the complete input side , including the sensor board, from the output.
Because of the opto-couplers, there is no problem to use the same 5V supply for multiple GCA_OK1 units.
The output is open collector and works with levels between 3 and 5.5 V.


The boards will be available soon, not produced yet.

gca_ok1-en.txt · Last modified: 2023/10/05 13:32 by phg