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TTL to PPL coverter

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I need a circuit or IC which can convert two phase Encoder signal with 5V to 24V with frequency about 1Mhz,

Would you please provide with something can perform that.

Thank you in advance


Well-Known Member
Let me see if I understand. You want to convert a pair of TTL signals from a rotary encoder that swing between 0V and 5V (TTL levels) into a pair of signals that swing between 0V and 24V at a frequency of 1 MHz.

The last requirement eliminates the use of a comparator like the LM339 or LM393. A modern comparator with an open collector output might be a candidate but I don't have a part number in mind. The idea would be to run the output from the encoder to one input, and use a voltage divider on the other input to set the threshold. The output would need a pullup resistor to +24V. The comparator will need a pretty big slew rate to keep up with a 1 MHz. signal.

Second choice would be a single transistor inverting level shifter. This would be a common emitter switch. You need to make sure that you pull the base up to +5V when the TTL output is high since a TTL gate will not source muuch current. When the TTL gate goes low it will sink plenty of current.
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