Control circuit for set-point or dual targeting schemes. Control circuit for set-point or dual targeting schemes. In this example, the operator inputs a desired value for inspiratory pressure or inspiratory flow (both for dual targeting). The controller is designed so that either pressure as a function of time (P(t)) or flow as a function of time (V̇(t)), is constant (K), the set value of inspiratory pressure or flow. Robert L Chatburn, and Eduardo Mireles-Cabodevila Respir Care 2011;56:85-102 (c) 2012 by Daedalus Enterprises, Inc.