Power amplifier with power monitor circuit

摘要

A power amplifier is disclosed for controlling the current flow through a load. The power amplifier includes a plurality of switching elements connected in bridge fashion with the load and a first predetermined power source for coupling the load across alternate output terminals of the power source in accordance with the levels of a plurality of control signals respectively applied to the plurality of switching elements. Circuitry is coupled to a second predetermined power source for generating the control signals. Logic circuitry, when enabled, is capable of coupling each of the control signals to the respective switching element. A power monitor circuit compares the voltage level of the second power source with a predetermined reference potential and generates a current disable signal when the voltage level is less than the reference potential. A disable circuit coupled to the power monitor circuit disables the coupling circuit in response to the presence of the current disable signal whereby further current flow through the load is inhibited.