A voltage-controlled current source (VCCS) is a key component in the electrical stimulation of neuronal tissue. We present a method for the evaluation of VCCS circuit architectures with applications in transcranial electrical stimulation (tES), covering theoretical analysis, numerical simulation studies, and validation with empirical measurements. The method is illustrated using two circuits: one with a single-ended, and one with differential output. These circuits, as well as the method used to evaluate them, were selected for being easy to reproduce, using generic hardware components at low cost. The method described has immediate practical application value in neuroscience research, where it can be used in the deployment and further development of VCCS circuit architectures.