摘要:
In one embodiment, the method of these teachings includes decomposing the output ripple voltage into its constituent components and utilizing the scale factor necessary for this decomposition to obtain the measure capacitance and ESR for a power supply/converter.
摘要:
A notch filter circuit includes first and second operational amplifiers, each having a capacitor connected from the amplifier output to the input. A third capacitor is connected between the second-amplifier input and the filter circuit input. A first switched-capacitor resistor is connected between the filter circuit input and the first-amplifier input. A second switched-capacitor resistor is connected between the first amplifier output and the second amplifier input. The second-amplifier output is connected to the filter circuit output. A third switched-capacitor resistor is connected between said filter circuit output and said first amplifier input; First and second programmable capacitor arrays are connected respectively in parallel with the third switched-capacitor resistor and in parallel with the first switched-capacitor resistor, so that a change only in the capacitance of the second capacitor array causes a corresponding change in the filter notch depth and a change only in the capacitance of the first capacitor array causes a corresponding change in the filter notch width. The first and second capacitor arrays each have a group of digital programming terminals that may be connected together for making fixed the ratio of the capacitance values of the two arrays. A digitally programmable voltage divider circuit connected in series with the second programmable capacitor array permits the independent programing of notch depth, i.e. without affecting notch width.
摘要:
An amplifier has a first stage employing a pair of differentially connected NMOS amplifier transistors, a second stage composed of a bipolar current mirror circuit and two charge pumps. Each charge pump may be a switching voltage multiplier circuit without the conventional output capacitor. The outputs of the two charge pumps are connected, respectively, to the collector of the current-mirror output transistor and to the commonly connected sources of the NMOS amplifier transistors. Each charge pump serves as both a pulse-voltage energizing source and a load to the amplifier. The amplifier is incorporated with a high-current NMOS transistor in an integrated circuit, wherein one differential input of the amplifier is connected to the source of the driver transistor at which an external load, e.g. a motor, may be connected. The output (collector) of the differential amplifier is connected to the gate of the NMOS driver transistor so that the load current through the driver transistor is held regulated to a value proportional to the input or reference voltage that is applied to the other input of the differential amplifier. The peak pulse voltage of each charge pump is greater than the DC supply voltage from which the driver transistor and the two charge pumps are energized so that the dynamic range of both the input control voltage and the amplifier output to the gate of the NMOS driver transistor is much greater than the DC supply voltage to the integrated circuit.
摘要:
An improved current pump for use in a Type II phase-locked loop including diodes employed as on-off switches for completing paths for a source current. Apparatus is disclosed for increasing the switching speeds of the diodes by ensuring that diode bias voltages undergo the smallest possible shifts required to switch the diodes.
摘要:
An improved charge pump for use in a phase-locked loop is disclosed in which there is only one current source, and in which all switching components pass current in the same direction. The charge pump may thus be constructed entirely of NPN transistors, which makes it possible to embody it in a single integrated circuit chip. The pump up and pump down currents inherently have the same magnitude and transient characteristics, thus minimizing steady-state errors.
摘要:
A first control system for a power supply includes a switch-mode DC-DC converter module and an FET gate drive module. The switch-mode DC-DC converter module receives an input voltage and generates first and second voltages, the first voltage powering a DC-DC control module. The FET gate drive module selectively drives a plurality of FETs of the power supply using the second voltage thereby generating a desired output voltage from the input voltage. A second control system is directed to driving the second voltage to a desired gate voltage, wherein the desire gate voltage is determined based on at least one of a plurality of operating parameters. A third control system includes controlling first and second voltages generated by a SIDO voltage converter based on the first and second voltages and a damping factor, and generating the damping factor based on current flowing through the inductor of the SIDO voltage converter.
摘要:
A method and apparatus for converting a DC voltage to a lower DC voltage, provides for conducting current from an input terminal, through an inductor to charge a capacitor connected to the inductor at an output terminal and to provide a varying range of load current from the output terminal, alternately switching the input terminal between a supply voltage and a ground potential to produce a desired voltage at the output terminal that is lower than the supply voltage, while providing the varying range of load current, and disconnecting the input terminal from both the supply voltage and the ground potential to reduce an increase in voltage at the output terminal caused by a substantial reduction in the load current, while current through the inductor adjusts in response to the reduced load current.
摘要:
A first control system for a power supply includes a switch-mode DC-DC converter module and an FET gate drive module. The switch-mode DC-DC converter module receives an input voltage and generates first and second voltages, the first voltage powering a DC-DC control module. The FET gate drive module selectively drives a plurality of FETs of the power supply using the second voltage thereby generating a desired output voltage from the input voltage. A second control system is directed to driving the second voltage to a desired gate voltage, wherein the desire gate voltage is determined based on at least one of a plurality of operating parameters. A third control system includes controlling first and second voltages generated by a SIDO voltage converter based on the first and second voltages and a damping factor, and generating the damping factor based on current flowing through the inductor of the SIDO voltage converter.
摘要:
A system includes a first switch connected to a voltage input and a switching node. A second switch is connected to the switching node and a reference potential. A first circuit generates first rising edges and first falling edges by comparing a voltage at the switching node to a first voltage reference. The first voltage reference is between the reference potential and the voltage input. A second circuit generates second rising edges and second falling edges by comparing the switching node voltage to a second voltage reference. The second voltage reference is less than the reference potential. The controller calculates delay times based on the first rising edges, the first falling edges, the second rising edges and the second falling edges. The controller generates drive signals for the first switch and the second switch based on a duty cycle and the delay times.
摘要:
In one embodiment, the digital pulse width modulator of these teachings includes comparators and a number of phases and capable of increasing resolution without increasing clock frequency. In another embodiment, the digital pulse width modulator (DPWM) of these teachings includes equality comparators and a number of phases and increases resolution without increasing clock frequency. A further embodiment of the system of these teachings includes a priority encoded comparator component (in one instance including a number of comparators) comparing duty cycle commands against preset minimums, that embodiment being referred to as a frequency Foldback component. Other embodiments and embodiments of the method of these teachings are also disclosed.