In accordance with embodiments of the present disclosure, an apparatus may include a signal path comprising a closed-loop analog pulse width modulator having a forward signal path and a feedback path, a variable resistor coupled to an output of the closed-loop analog pulse width modulator, and a control circuit configured to modify the variable resistor in order to modify an output impedance outside of the feedback path of the closed-loop analog pulse width modulator responsive to a condition for switching between a high output impedance mode and a low output impedance mode of the closed-loop analog pulse width modulator or vice versa.