Abstract: A programmable cochlear implant system utilizes multiple-resolution current sources and flexible data-encoding scheme for transcutaneous transmission. In certain embodiments, the number of current sources may be equal to or greater than 2, but equal or less than N?1, where N is the number of electrodes. The multi-resolution current source may introduce offset currents to achieve perceptually-based multiple resolutions with high resolution at low amplitudes and low resolution at high amplitudes. The flexible data-encoding scheme may allow arbitrary waveforms in terms of phase polarity, phase duration, pseudo-analog-waveform, while producing high-rate and high-temporal-precision stimulation. In one embodiment, a 2-current-source system may support simultaneous and non-simultaneous stimulation as well as monopolar, bipolar, pseudo-tripolar, and tripolar electrode configurations.