I'm making a TENS unit for a college project.
I want it to generate pulses between 140 and -140V at its maximum value. Before someone says this is dangerous, let me say it is not. The pulses generated are very far from each other as the pulse width is 200us and the distance between pulses is 10ms at its minimum value. The human skin has high impedance(KOhms or MOhms depending of multiple factors) and acts as an RC circuit.
Im using a STM32F0 microprocessor which gives me a signal between 0 and 3.3V, then I amplify it getting a signal between -14 and 14V.
This works perfectly, but the problem occurs when I connect this signal to a 1:10 pulse transformer (DA2032-AL) because i want a signal between +-140V at max.
I have tried everything possible but only i can get the original signal or 0V.
I dont know if this transformer isn't the right one or if im doing something wrong, if someone could give me some help i'd appreciate it.
Sorry if i made some linguistical mistakes, english is not my main language
I attach the main circuit down here v
I want it to generate pulses between 140 and -140V at its maximum value. Before someone says this is dangerous, let me say it is not. The pulses generated are very far from each other as the pulse width is 200us and the distance between pulses is 10ms at its minimum value. The human skin has high impedance(KOhms or MOhms depending of multiple factors) and acts as an RC circuit.
Im using a STM32F0 microprocessor which gives me a signal between 0 and 3.3V, then I amplify it getting a signal between -14 and 14V.
This works perfectly, but the problem occurs when I connect this signal to a 1:10 pulse transformer (DA2032-AL) because i want a signal between +-140V at max.
I have tried everything possible but only i can get the original signal or 0V.
I dont know if this transformer isn't the right one or if im doing something wrong, if someone could give me some help i'd appreciate it.
Sorry if i made some linguistical mistakes, english is not my main language
I attach the main circuit down here v
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