Abstract: A power regulator includes a pass transistor, a feedback circuit, an error amplifier and a protection circuit. The pass transistor receives an unregulated first power supply voltage, and an output terminal of the power regulator outputs an output voltage varying depending upon a control signal. The feedback circuit senses a current flowing through the pass transistor and generates a feedback signal. The error amplifier compares a reference signal to the feedback signal and generates a control signal varying depending upon a voltage difference between the reference signal and the feedback signal. The protection circuit scales down a current flowing through the pass transistor by a prescribed ratio and changes a voltage of the control signal when the scaled-down current has a value higher than a prescribed value.

Abstract: An auto fusing circuit for automatically performing fusing operations by application of one time fuse enable signal is described. The auto fusing circuit includes a primary fuse block for receiving a fuse enable signal as an enable signal, and performing a fusing operation, and a plurality of secondary fuse blocks connected to an output terminal of the primary fuse block in series for respectively receiving an out signal of the previous fuse block as an enable signal, and sequentially performing fusing operations. The primary fuse block and the secondary fuse blocks are activated by an enable of each of select signals, or deactivated by a disable of each of the select signals. According to the auto fusing circuit, the fusing operations are sequentially performed with a single application of fuse enable signal, and a test time can be reduced.

Abstract: An auto fusing circuit for automatically performing fusing operations by application of one time fuse enable signal is described. The auto fusing circuit includes a primary fuse block for receiving a fuse enable signal as an enable signal, and performing a fusing operation, and a plurality of secondary fuse blocks connected to an output terminal of the primary fuse block in series for respectively receiving an out signal of the previous fuse block as an enable signal, and sequentially performing fusing operations. The primary fuse block and the secondary fuse blocks are activated by an enable of each of select signals, or deactivated by a disable of each of the select signals. According to the auto fusing circuit, the fusing operations are sequentially performed with a single application of fuse enable signal, and a test time can be reduced.

Abstract: There is provided a mute control circuit which is simplified to efficiently remove switching noise during the muting of each output and reducing the number of connection pins required for a given integrated circuit. The mute control circuit includes a pulse generator for receiving the each mute signal and generating a control pulse; a charge/discharge signal generator for receiving the control pulse and generating a charge/discharge signal and a switching control signal; a controller for receiving the charge/discharge signal and controlling the mute operation of the output terminal according to the switching control signal; and a switching signal generator for receiving the mute signal, generating a switching signal according to the switching control signal of the charge/discharge signal generator, and supplying the switching signal to the controller.

Abstract: A vocal mix circuit shifts the phase of a mixed audio signal using a phase shifter, and achieves a mixed signal emphasizing the voice components thereof, by subtracting a signal which is not shifted from the signal shifted by the phase shifter. Gain through the above steps is controlled by the gain controller. Then, operators process both the initial signals and the signal through the phase shifter and the gain controller. Accordingly, the vocal mix circuit enables a person to hear with high sensitivity, has a simple circuit, and reduces the number of external pins.