Abstract: A ternary modulation scheme for filterless switching amplifiers with reduced EMI reduces the common mode component of the signal by allowing only one state with zero differential voltage across the load to exist. The ternary modulation scheme is more efficient than the quaternary modulation scheme when applied to class-D filterless switching amplifiers since the gates of the power MOSFETs are being charged and discharged at only a small duty cycle instead of 50% duty cycle.

Abstract: A ternary modulation scheme for filterless switching amplifiers with reduced EMI reduces the common mode component of the signal by allowing only one state with zero differential voltage across the load to exist. The ternary modulation scheme is more efficient than the quaternary modulation scheme when applied to class-D filterless switching amplifiers since the gates of the power MOSFETs are being charged and discharged at only a small duty cycle instead of 50% duty cycle.

Abstract: A low voltage 485-driver circuit that meets the standard leakage and 1.5 voltage differential output requirements of the TIA/EIA-485 specification while operating from a 3V supply. The circuit avoids the voltage drop across the series Schottky diodes in the output driver of a conventional 485-driver by moving the Schottky blocking diodes from the output stage signal path to the pre-driver stage so that the output stage is restricted to back-gate biasing only. In addition, the circuit uses stacked NMOS transistors to maintain lower voltage across each NMOS transistor in order to prevent hot-carrier injection. This allows lower voltage rated output NMOS transistors to be used, resulting in higher speed operation. The circuit will withstand excessive common mode voltages in the range of +12V to −7V applied to the output while in either signaling ON state or the disabled OFF state.

Abstract: A low voltage 485-driver circuit that meets the standard leakage and 1.5 voltage differential output requirements of the TIA/EIA-485 specification while operating from a 3V supply. The circuit avoids the voltage drop across the series Schottky diodes in the output driver of a conventional 485-driver by moving the Schottky blocking diodes from the output stage signal path to the pre-driver stage so that the output stage is restricted to back-gate biasing only. In addition, the circuit uses stacked NMOS transistors to maintain lower voltage across each NMOS transistor in order to prevent hot-carrier injection. This allows lower voltage rated output NMOS transistors to be used, resulting in higher speed operation. The circuit will withstand excessive common mode voltages in the range of +12V to −7V applied to the output while in either signaling ON state or the disabled OFF state.

Abstract: A system for driving hard disk drive spindle and actuator motors is disclosed. The system comprises a spindle motor control circuit (120), a spindle motor power circuit (210), an actuator motor control circuit (110), and an actuator motor power circuit (210). The spindle motor control circuit (120) and the actuator motor control circuit (110) are formed on a first substrate (100). The spindle motor power circuit (210) and the actuator motor power circuit (220) are formed on a second substrate (200). The system also includes at least one disk (22) attached to a rotatable spindle (21), a spindle motor (400) for receiving and being energized by the spindle motor power signals, and for controlling the rotation of the spindle (21), a plurality of disk read heads (12) adjacent to the disks (22), and an actuator motor (300) for receiving and being energized by the actuator motor power signals, and for controlling the position of the disk read heads (12).

Abstract: A source cell having reduced area and reduced polysilicon window width requirements for use as the source region in a DMOS transistor is disclosed, comprising: a source region of semiconductor material disposed on a semiconductor substrate; a plurality of backgate contact segments of predetermined size and separated by predetermined distances; and a plurality of source contact windows alternating with the backgate contact segments so that a narrow source contact region is formed of alternating source contact and backgate contact material. A DMOS transistor embodying the source region including the backgate contact segments and windowed source contacting regions of the invention is disclosed. An integrated circuit providing an array of DMOS transistors having the improved source regions of the invention is disclosed.Other devices, systems and methods are also disclosed.

Abstract: A protection device, circuit, and a method of forming the same. A field oxide drain extended nMOS (FODENMOS) transistor (10) is located in an epitaxial region (16). The FODENMOS transistor (10) comprises a field oxide region (36a) that extends from the source diffused regions (22) to over a portion of the extended drain region (20). A drain diffused region (24) is located within the extended drain region (20). A gate electrode (40) may be located above the field oxide region (36a) if desired. Accordingly, there is no thin oxide interface between the gate electrode (40) and the extended drain region (20) that can lead to low ESD protection.

Abstract: A source cell having reduced area and reduced polysilicon window width requirements for use as the source region in a DMOS transistor is disclosed, comprising: a source region of semiconductor material disposed on a semiconductor substrate; a plurality of backgate contact segments of predetermined size and separated by predetermined distances; and a plurality of source contact windows alternating with the backgate contact segments so that a narrow source contact region is formed of alternating source contact and backgate contact material. A DMOS transistor embodying the source region including the backgate contact segments and windowed source contacting regions of the invention is disclosed. An integrated circuit providing an array of DMOS transistors having the improved source regions of the invention is disclosed.Other devices, systems and methods are also disclosed.

Abstract: Methods and circuits of integrated DMOS, CMOS, NPN, and PNP devices include self-aligned DMOS (411) with increased breakdown voltage and ruggedness for recovery from transients including additional Zener diodes (402/474).

Abstract: A traveling valve assembly is provided for use in subsurface gravity type pumping systems and is responsive to reciprocating motion to manipulate a rotary valve head relative to a valve seat between open and closed positions, and to fluid pressure to manipulate a ball member and a slidable seal member relative to seat members between open and closed positions. Reciprocating motion is converted to rotary motion by means of a journaled spiral groove portion of the rotary valve member. The traveling valve assembly is provided with multiple seals to prevent high pressure gas from blowing through the pump when pumping oil.