Abstract: A masking material (14) is formed on a foundation layer (12) and a substrate (10). A mask (16) is disposed onto the masking material (14) where a trench (26) is desired to be formed. An etch step removes all of the masking material (14) except at regions where the mask (16) was formed leaving a protruding portion (18) with an opening (20) on either side. An epi layer (24), is grown on the foundation layer (12) adjacent to the protruding portion (18) in the opening (20). A wet oxide etch process is used to remove the protruding portion (18) leaving a trench (26) formed in the epi layer (24). To complete the process, a silicon wet etch process is used to round off the corners at an edge (28) of the trench (26).

Abstract: An audio amplifier system (10) is formed to include a voltage reference (16). The voltage reference (16) is formed to utilize a filter having a first cut-off frequency when the output (14) of the voltage reference (16) is less than a first value and to use a second cut-off frequency when the output (14) is greater than the first value.

Abstract: A method of making a semiconductor device (100) by attaching a top surface of a first laminate (630) to a bottom surface of a second laminate (650) to form a leadframe (620) and mounting a semiconductor die (102) to the leadframe to form the semiconductor device. The first semiconductor die is encapsulated with a molding compound (108) and material is removed from the first laminate to form a mold lock (120) with the molding compound.

Abstract: A switching power supply (30) includes a compensation circuit (58) which monitors a transformers (36) primary side to provide a voltage compensation signal, COMPV. A transistor inductor current, VTRAN is fed to the compensation circuit (58) to establish a DC level proportional to the peak primary side inductor current flowing through a power transistor (38). VTRAN is fed to a multiplier circuit (98). The output of the multiplier circuit (98) is scaled by a resistor (80) to establish the compensation signal, COMPV at the output to the compensation circuit (58). When at current limit, an amplifier (66) becomes saturated causing a diode (68) to reverse bias, effectively removing compensation signal COMPV from operation. An amplifier (70) falls into a linear region and a diode (74) becomes forward bias forcing compensation signal COMPC into operation providing regulation to the output of the switching power supply (30) at current limit.