Passive recharge phase

A commonly used neuro-stimulation scheme is to inject charge with a constant-current pulse, then recover the charge by clamping the circuit output back to ground voltage. In the passive recharge phase, the circuit operates similarly to the recharge... 

For high-frequency stimulation, active recharge can be used to accelerate the recharge speed. A circuit designed to provide active recharge would actively drive both the cathodic and anodic phases. However, at the end of both active phases, the circuit still needs to incorporate a shorting phase, as done in passive recharge. 

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