Rockford Corporation

David Dean Baker

James C Strickland

Mark D Albers

Disclosed boost amplifiers are used with a BTL amplifier that outputs balanced audio signals and that has an output current capacity and a dynamic power capacity. Disclosed amplifiers include an audio amplifier with a dynamic power capacity and that amplifies the balanced audio signals and applies them to a load, at least one diode that receives audio signals and produces single-ended input power signals, and at least one regulator that converts the single-ended input power signal into a regulated power signal of a higher magnitude. The boost regulator presenting a variable input impedance to the BTL amplifier such that the output current capacity of the BTL amplifier is not exceeded. Disclosed amplifiers also include a DC power reservoir that stores power from the regulated power signal and supplies sufficient power that the dynamic output power capacity of the audio amplifier exceeds the dynamic power capacity of the BTL amplifier.

Amplification of signals output from bridge-tied load audio amplifiers

Methods and apparatus for audio signal clip detection are disclosed. The clip detectors may receive audio signals, from which peak reference signals, indicative of the highest voltage of the received audio signals, may be derived. The received audio signals may also be differentiated and phase-lagged to produce differentiated audio signals which may, in turn, be rectified to produce rectified differentiator signals. The rectified differentiator signals and the peak reference signals may be compared to thereby produce clip detect signals indicative of whether the received audio signals are clipped. The clip detect signals may then be used to indicate whether the received audio signal are clipped.

Audio signal clip detection

An amplifier device including an amplifier having an input for receiving an audio input signal and an output for sending an output signal to a load. A boosted-rail circuit is connected to a power source and has a single boosted rail connected to the BTL amplifier. Also, a common-mode circuit is coupled to the boosted-rail circuit and the BTL amplifier. The common-mode circuit sends a common-mode signal to the BTL amplifier that will dynamically track the output voltage supplied from the boosted-rail circuit to the BTL amplifier. In operation, the boosted-rail circuit reacts to the BTL amplifier and switches from a non-boost mode to a boost mode to increase the output voltage supplied to the BTL when the BTL amplifier requires additional voltage.

Boosted-rail amplifier

A switching amplifier including a voltage sensor circuit connected to a high voltage supply rail for measuring the power supply voltage. A current sensor circuit is connected to the high voltage supply rail for measuring the power supply current. An error amplifier is connected to the switching amplifier and receives one or more values based on the measurements taken by the voltage sensor and current sensor, and the error amplifier produces an error signal when a predetermined power limit is exceeded. A signal limiting circuit is connected to the error amplifier and the switching amplifier and limits the output power to rated power at any rated load impedance when the error amplifier produces the error signal. This switching amplifier is capable of automatically limiting output power at rated power into all rated load impedances, and dynamically reacts to the frequency-dependant impedance of a typical audio system.

Growing community of inventors

Gilbert, AZ, United States of America

David Dean Baker