An apparatus for controlling a switching amplifier.

摘要

An apparatus for controlling the output of a switching amplifier (38) includes a signal dividing circuit (14) which generates a delayed replica (S1) of the carrier signal and a doubled signal (S2) having twice the carrier frequency. The doubled signal is effective for establishing a second time delayed signal relative to the first time delayed signal (S1A). The first and second time delayed signals are logically operated on so that a three state output representing the carrier signal is attained. A summing amplifier (26) utilizes the two time delayed signals to generate this three state output whereby if the two time delayed signals are out-of-phase, a zero voltage is connected to the drive portion (40, 42) of the switching amplifier thereby limiting the output of the switching amplifier.