摘要:
A system and method is provided to compensate an amplifier circuit for changes in a load impedance in order to maintain a substantially optimum performance for the amplifier. More specifically, if the load impedance increases, then the amplifier is reconfigured to produce an output impedance that is likewise increased. One way of reconfiguring the amplifier for a load impedance increase is to increase the supply voltage to the device. The increase in the supply voltage to the device increases the rail to rail operation of the device. This would allow more dynamic range for the system performance. Assuming the current is substantially constant, the impedance seen the output of the amplifier will increase and be multiplied up to the impedance desired by the load resulting in a more optimum power transfer. Other parameters, such as the input drive and bias voltage to the amplifier can be changed in order to improve the performance of the amplifier.
摘要:
A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification. The semiconductor device can be configured by itself or with a complimentary device to form push-pull operations.
摘要:
The systems and methods monitor a subject's blood pressure under a constant applied pressure. Measurements taken from a pressure measuring element and a pulse sensing element are combined to determine the subject's systolic and diastolic pressure. The systolic pressure is measured directly by the pressure measuring element, and the diastolic pressure is determined indirectly by using a pulse waveform to extrapolate portions of a pressure waveform. The systems and methods can be employed in any number of applications, including, without limitation, taking a single reading from a subject, continuously monitoring a subject, or evaluating a subject during physical exertion.
摘要:
A four-way power combiner/splitter is disclosed that includes a first transmission line having a first non-grounding conductor and a first grounding conductor, wherein the first grounding conductor is grounded at a first end of the first transmission line. The combiner/splitter also has a second transmission line having a second non-grounding conductor and a second grounding conductor, wherein the second grounding conductor is grounded at a first end of the second transmission line. The non-grounding conductors of the first and second transmission lines are electrically coupled together at the respective first ends of the first and second transmission lines. An output/input port is provided that is electrically coupled to the first and second non-grounding conductors at the respective first ends of the first and second transmission lines. Additionally provided are a first input/output port electrically coupled to the first non-grounding conductor at a second end of the first transmission line, a second input/output port electrically coupled to the first grounding conductor at the second end of the first transmission line, a third input/output port electrically coupled to the second non-grounding conductor at a second end of the second transmission line, and a fourth input/output port electrically coupled to the second grounding conductor at a second end of the second transmission line.
摘要:
A field effect transistor is disclosed having a relatively high doped region (of the same type dopant as the channel) to reduce the change in the depletion region within the channel with changes in the drain voltage (Vd). Changes in the drain current (Id) with changes in the drain voltage (Vd) is a cause of non-linearity for traditional MOSFET. Because of the additional higher doped region provided in the channel, the depletion region within the higher doped region changes less with changes in the drain voltage (Vd). The higher doped region is situated near the top of the channel, where most of the drain current flows. Thus, the higher doped region dominates the drain current through the device. Since the drain current is less susceptible to changes in drain voltage (Vd), a more linear device results.
摘要:
A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification. The semiconductor device can be configured by itself or with a complimentary device to form push-pull operations.
摘要:
A compensation circuit and method for compensating for the threshold shift in an irradiated MOSFET. The method determines the gate threshold voltage to body voltage relationship to vary the body voltage with radiation. The compensation circuit (10) has at least one MOSFET (Q2) having the same channel type as the MOSFET being compensated (Q1). The at least one matching MOSFET (Q2) is connected to the gate of the MOSFET (Q1) being compensated. At least one MOSFET (Q3, Q4) having a channel type that is different from the channel type of the MOSFET (Q1) being compensated is connected to the gate of the matching MOSFET (Q2). The result is that the compensation circuit (10) controls a negative shift in the body voltage of the MOSFET (Q1) being compensated resulting in a higher threshold voltage.
摘要:
A system and method is provided to compensate an amplifier circuit for changes in a load impedance in order to maintain a substantially optimum performance for the amplifier. More specifically, if the load impedance increases, then the amplifier is reconfigured to produce an output impedance that is likewise increased. One way of reconfiguring the amplifier for a load impedance increase is to increase the supply voltage to the device. The increase in the supply voltage to the device increases the rail to rail operation of the device. This would allow more dynamic range for the system performance. Assuming the current is substantially constant, the impedance seen the output of the amplifier will increase and be multiplied up to the impedance desired by the load resulting in a more optimum power transfer. Other parameters, such as the input drive and bias voltage to the amplifier can be changed in order to improve the performance of the amplifier.
摘要:
A compensation circuit and method for compensating for the threshold shift in an irradiated MOSFET. The method determines the gate threshold voltage to body voltage relationship to vary the body voltage with radiation. The compensation circuit has at least one MOSFET having the same channel type as the MOSFET being compensated. The at least one matching MOSFET is connected to the gate of the MOSFET being compensated. At least one MOSFET having a channel type that is different from the channel type of the MOSFET being compensated is connected to the gate of the matching MOSFET. The result is that the compensation circuit controls a negative shift in the body voltage of the MOSFET being compensated resulting in a higher threshold voltage.
摘要:
A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification.