Abstract: A system for obtaining flexible frequency selection and high efficiency on a low frequency magnetic field position determination.

Abstract: A solid state relay and a method for controlling a signal path between an AC-signal output and a load in a power amplifier assembly are disclosed. The relay comprises a first and a second MOSFET having a common gate junction, a common source junction and wherein and wherein a drain terminal of a first MOSFET and a drain terminal of a second MOSFET form relay terminals. The solid state relay further comprises a control circuit comprising a positive side comprising a first controlled current generator configured to provide a first control current to the gate junction, and a negative side comprising a current mirror circuit configured to sink a second current from the source junction. Hereby, a generic solid state speaker relay has been disclosed. The relay performs up to the most stringent demands regarding pop/click on high quality products. It can be used to ground wire break, hot wire break and BTL (Bridge Tied Load) break.

Abstract: An amplifier arrangement comprising first and second power amplifiers (T1, T2) having drains connected to positive and negative drive voltages, respectively, and gates connected to an input signal. The arrangement further comprises first and second current sensors (1, 2) for detecting first and second drain currents from the power amplifiers, processing circuitry (3) adapted to identify the smallest drain current, and a feedback control loop (5) and means for driving a bias current dependent on a feedback signal through a resistor connected between the input signal and the gate of an inactive one of the first and second power amplifiers. The control loop will keep the idle current constant in the transistor with the lowest current (the inactive transistor). Thereby, the current running in the transistor which does not deliver current to the load will be fixed at a desired value.

Abstract: A solid state relay and a method for controlling a signal path between an AC-signal output and a load in a power amplifier assembly are disclosed. The relay comprises a first and a second MOSFET having a common gate junction, a common source junction and wherein and wherein a drain terminal of a first MOSFET and a drain terminal of a second MOSFET form relay terminals. The solid state relay further comprises a control circuit comprising a positive side comprising a first controlled current generator configured to provide a first control current to the gate junction, and a negative side comprising a current mirror circuit configured to sink a second current from the source junction. Hereby, a generic solid state speaker relay has been disclosed. The relay performs up to the most stringent demands regarding pop/click on high quality products. It can be used to ground wire break, hot wire break and BTL (Bridge Tied Load) break.