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I want to make a device for medical purposes.

I have a bit of experience with op-amp.

I tried many schemes and this gave better results: enter image description here

I need a PWM on the frequency of 100kHz currents within ± 0.05mA ~ 2mA with the ability to adjust it using a DAC.

Electrodes are connected to the ear of the patient, I tried to create a skin model of L3, C5, R19.

I get this kind of current diagram: enter image description here

For me it's very important for the pulses to be rectangular and without emissions, how can I achieve it?

Any of your tips on choosing a scheme and components.

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  • \$\begingroup\$ Define "emissions". \$\endgroup\$ – winny Dec 19 '17 at 21:57
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    \$\begingroup\$ "rectangular" and "without emissions" are conflicting goals. The faster the edges, the more emissions. \$\endgroup\$ – The Photon Dec 19 '17 at 22:22
  • \$\begingroup\$ But there were schemes that worked without emissions I know exactly what is possible \$\endgroup\$ – Fangog Dec 20 '17 at 8:13
  • \$\begingroup\$ Please elaborate on your definition of 'emissions'. Do you mean the spikes at the top on the rising edge? Those are called 'overshoot' and the little 'wiggle' afterwards is called 'ringing'. \$\endgroup\$ – Oldfart Dec 21 '17 at 10:03
  • \$\begingroup\$ They are also at the bottom. Sorry my English is bad. \$\endgroup\$ – Fangog Dec 21 '17 at 21:56

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