Multi-layer structures are electrochemically fabricated by depositing a first material, selectively etching the first material, depositing a second material to fill in the voids created by the etching, and then planarizing the depositions so as to bound the layer being created and thereafter adding additional layers to previously formed layers. The fixed jaw and module board are constructed of two separating boards with a seam between them. The implementation of the throttling process can be varied, to include additional levels of response or finer gradations of the response, to include subsets of a class of services. The valve portion is disposed in the valve chamber for dividing the valve chamber into a bleed chamber, a backpressure chamber and a communication passage.