摘要:
A method of manufacturing an integrated circuit having a buried layer of a low doped type of conductivity (2) and a buried layer of a highly doped type of the same conductivity (3) by masking a substrate (1) so as to define open areas on the substrate where it is desired to provide the two buried layers and doping the open areas of the substrate with a low concentration of dopants to form the low doped type of buried layer (2) is formed. Then one open area where the low doped type of buried layer (2) is formed is masked and the other open area is doped with a high concentration of dopants to form the highly doped type of buried layer (3).
摘要:
A current sourcing output stage for a high voltage operational amplifier receives a low voltage input signal (V IN ) and provides a high current output signal corresponding to the low voltage input signal at an output terminal (8). A first PNP transistor (Q1) is coupled between a voltage supply (V CC ) and a plurality of cascaded PNP transistors (Q2, Q3, Q8 - Q11) coupled to the output terminal (8). The base of the first PNP transistor (Q1) is coupled to receive the input signal (V IN ) and the bases of the cascaded PNP transistors are coupled to receive different bias voltages A control circuit (Q5 - Q7, R1 - R5) is coupled to the voltage supply (V CC ) and has an input coupled to the output terminal (8) for deriving a plurality of bias voltages and to the cascaded PNP transistors (Q2, Q3, Q8 - Q11) to supply the bias voltages to the respective bases of the cascaded PNP transistors, so that the cascaded PNP transistors (Q2, Q3, Q8 - Q11) are biased by bias voltages dependent on the voltage swing of the output signal.
摘要:
A feedback and shift unit is arranged to reduce to a minimum the number of processing steps required in a processor, such as a DSP, to achieve a particular operating function, such as a linear feedback shift or a stepping function used by encryption algorithms. The feedback and shift unit (50) comprises a linear feedback shift register (52) for storing a value of the feedback and shift unit. A tap register (56) stores a tap position indicator indicative of tap positions for the feedback and shift unit (50). An input provides data to the feedback and shift unit. A feedback matrix, coupled to receive the data from the input, provides data bits, generated in response to the data and the tap position indicator, that are shifted into the linear feedback shift register (52) to form the value stored therein.
摘要:
A power supply for an electric appliance having an operating mode and a standby mode includes a transformer block (9) for producing a constant power output into two low voltage outputs (Vc and Vcc), an operating power supply circuit (2) coupled to one of the two low voltage outputs (Vcc) to power the appliance during the operating mode, and a receiver circuit (3) coupled to the other low voltage output via an impedance path (14, 15). The receiver circuit (3) includes a switch (17) for switching a very low impedance into a path parallel with the first impedance when it receives a signal indicating that the appliance is to enter the standby mode, so that the voltage at the other low voltage output (Vcc) is reduced, thereby increasing the current drawn by the receiver circuit (3) and thus reducing the power available to the operating power supply circuit (2).
摘要:
A scaleable laser and control unit (58) is used to differentially heat portions of a semiconductor substrate (40) during downstream etching. Such differential heating provides a differential etch rate for each portion heated resulting in improved uniformity and reduced etch induced surface damage. An etching chamber (50) capable of containing the downstream plasma and providing a direct line of sight between the substrate (40) and the scanable laser unit (58) is provided. In addition, the system provides for dynamic updating of the process by in situ etch rate and temperature measurements.
摘要:
A switched capacitor differential circuit switches first and second differential input signals (Vinp1, Vinp2) to respective inputs (A, B) of an operational amplifier (12) via respective first and second signal paths. Each signal path includes a coupling capacitor (13, 14) and two switching devices (2, 3 and 4, 5) to switch the input signals to charge the capacitors at a first phase of a clock signal and to discharge the capacitors onto the inputs of the amplifier at a second phase of the clock signal. In order to remove common mode spikes from transferring to the amplifier, a pair of comon mode capacitors (16, 17) are coupled between the inputs and a common node (15), which is coupled via a pair of switches (6, 7) to the first and second signal paths between the capacitors and the second of the switching devices so that the coupling capacitors are discharged relative to the common node.
摘要:
A capacitor (58) for an integrated circuit having a conductive trench (50), disposed below a bottom electrode layer (52), that electrically connects the bottom electrode layer to a semiconductor substrate (14, 16). The conductive trench eliminates the need for a top-side contact to the bottom electrode layer. The semiconductor substrate is, for example, connected to ground.
摘要:
A method of forming a package assembly (10) including a package (12) that encapsulates an electronic die. A leadframe (30) has edge rails (32), and the die is disposed on the leadframe. The package is formed around the die to encapsulate it, and the leadframe is trimmed to provide a plurality of leads (14) protruding from a first side of the package. This trimming also provides a support (16) connected to a second side of the package. The support is bent to be substantially orthogonal to the common plane containing the leads. A mounting tip (26) on the support is thus disposed outside of the common plane. This support improves the rigidity and natural bending frequency of the package assembly.
摘要:
A noise cancelling circuit (1) is used with a D/A converter , the converter including a first modulator (11) and a data output. The circuit (1) comprises an error measuring arrangement (12, 13, 14) for measuring a quantization error signal of the modulator (11). A filter (19) receives the error signal and provides a filtered error signal. A filter compensator (17) coupled to the data output provides a compensated output. A scaler (15) coupled to receive the filtered error signal provides a scaled filtered error signal. A second modulator (16) coupled to receive the scaled filtered error signal provides a single bit stream of error data. A summing arrangement (18) sums the single bit stream of error data and the compensated output from the first modulator and provides a corrected output, such that the error signal is filtered, scaled and modulated and the data output is compensated such that the corrected output is obtained having a substantially reduced quantization error.
摘要:
An insulated gate semiconductor device (10) is formed having a buffer layer (13) having a graded dopant profile. The graded dopant profile improves the reverse blocking voltage of the device (10) while maintaining the switching speed.