A high voltage stimulator for small electrode electrocutaneous stimulation

A high voltage stimulator has been designed to allow transcutaneous stimulation of tactile fibers of the fingertip. The output stage is based upon an improved Howland current pump topology, modified to allow high load impedances and small currents. The current output accuracy is better than 15% for 1 to 10 mA for 30 /spl mu/sec pulses. The rise time for square pulses is less than 2 /spl mu/sec. Common mode latch-up power supply problems are discussed.