Abstract: A programmable analog tile integrated circuit is configured over a standardized bus by communicating tile configuration information from a first integrated circuit tile, through a second integrated circuit tile, to a third integrated circuit tile. Each of the three integrated circuit tiles is part of an integrated circuit. The standardized bus is formed when the tiles are placed adjacent one another. Data bus and control signal conductors of the adjacent tiles line up and interconnect such that each signal conductor is electrically connected to every tile. Tile configuration information may be written to a selected register identified by an address in any selected one of the tiles using the data bus and control lines, regardless of the relative physical locations of the tile sending and the tile receiving the information. Thus, tile configuration information may pass from one tile to another tile, through any number of intermediate tiles.

Abstract: A flyback AC/DC switching converter has a constant voltage (CV) mode. The CV mode has sub-modes. In one sub-mode (“mid output power sub-mode”), the output voltage (VOUT) of the converter is regulated using both pulse width modulation and pulse frequency modulation. Both types of modulation are used simultaneously. In a second sub-mode (“low output power sub-mode”), VOUT is regulated using pulse width modulation, but the converter switching frequency is fixed at a first frequency. By setting the first frequency at a frequency above the frequency limit of human hearing, an undesirable audible transformer humming that might otherwise occur is avoided. In some embodiments, the converter has a third sub-mode (“high output power sub-mode”), in which pulse width modulation is used but the switching frequency is fixed at a second frequency. By proper setting of the second frequency, undesirable EMI radiation and other problems that might otherwise occur are avoided.

Abstract: A power converter having a switched capacitor buck/boost operation has first and second switches coupled to a first switching node, third and fourth switches coupled to a second switching node, a capacitor coupled between the first and second switching nodes, and an inductor coupled to the first switching node. A switch controller controls the switches to operate in voltage step-down mode and voltage step-up mode depending on a difference between converter output voltage VOUT and converter input voltage VIN. In a buck-optimized topology operating in a step-down mode, an output current flowing through the first switching node flows through only one switch at a given time. In a boost-optimized topology operating in a step-up mode, an output current flowing through the first switching node flows through only one switch at a given time. As a result, a more compact and efficient power converter may be realized at lower cost.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: A step-down (buck) switching regulator regulates output current without sensing a current external to a converter integrated circuit. The regulator generates a set current that is indicative of a predetermined current level to which the output current is regulated. The regulator generates a sense current whose magnitude is proportional to an inductor current flowing through a power switch during an on time. During a first time period, the sense current is less than the set current. During a second time period, the sense current is greater than the set current. The output current of the regulator is maintained at the predetermined current level such that the first time period is equal to the second time period when the output current equals the predetermined current level. The set current is compared to the sense current in circuitry inside a bootstrap power generator whose voltage fluctuates with the voltage across the inductor.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls a switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the frequency and pulse width controls the peak of the inductor current.

Abstract: An average current-mode controlled converter has a buck mode, a boost mode, and a four-switch mode. In one example, the converter operates in one of the three modes, depending on the difference between the converter output voltage VOUT and the converter input voltage VIN. Whether the four-switch mode is a full-time four-switch mode or a partial four-switch mode is user programmable. The novel converter can also be programmed to operate in other ways. For example, the converter can be programmed so that there is no intervening four-switch mode, but rather the converter operates either in a buck or a boost mode depending on VOUT-VIN. The converter can also be programmed so that the converter always operates in a conventional full-time four-switch mode. In one embodiment, the converter is programmed by setting an offset between two internally generated ramp signals and by setting associated limiting and inverting circuits.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls a switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the frequency and pulse width controls the peak of the inductor current.

Abstract: A flyback AC/DC switching converter has a constant voltage (CV) mode. The CV mode has sub-modes. In one sub-mode (“mid output power sub-mode”), the output voltage (VOUT) of the converter is regulated using both pulse width modulation and pulse frequency modulation. Both types of modulation are used simultaneously. In a second sub-mode (“low output power sub-mode”), VOUT is regulated using pulse width modulation, but the converter switching frequency is fixed at a first frequency. By setting the first frequency at a frequency above the frequency limit of human hearing, an undesirable audible transformer humming that might otherwise occur is avoided. In some embodiments, the converter has a third sub-mode (“high output power sub-mode”), in which pulse width modulation is used but the switching frequency is fixed at a second frequency. By proper setting of the second frequency, undesirable EMI radiation and other problems that might otherwise occur are avoided.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: A low-cost integrated circuit is used as a secondary side constant voltage and constant current controller. The integrated circuit has four terminals and two amplifier circuits. A first amplifier circuit is used to sense a voltage on a FB terminal and in response to cause a first current to flow through an OPTO terminal. A second amplifier circuit is used to sense a voltage between a SENSE terminal and a SOURCE terminal and in response to cause a second current to flow through the same OPTO terminal. The FB terminal is used for output voltage feedback and is also used to supply power onto the integrated circuit. The SOURCE terminal is used for output current feedback and is also used as power supply return for the integrated circuit. The cost of the integrated circuit is reduced by having only four terminals.

Abstract: Systems and methods for varying dye loads. A fluid ejection apparatus includes a reservoir and an assembly. The reservoir stores ink with a first dye load and the assembly receives the ink with the first dye load from the reservoir. To obtain ink with higher dye load, the assembly evaporates a portion of the liquid solvent in the ink to obtain ink with a higher dye load.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls a switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the frequency and pulse width controls the peak of the inductor current.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls a switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the frequency and pulse width controls the peak of the inductor current.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: An inductor current flows through an inductor of a flyback converter. In a constant voltage mode, the pulse width of an inductor switch control signal is adjusted to maintain a constant output voltage of the flyback converter. The inductor switch control signal controls a switch through which the inductor current flows. In a constant current mode, a comparing circuit, a control loop and a clamp generator circuit are used to maintain the peak level of inductor current. The comparing circuit generates a timing signal based on the ramp-up rate of the inductor current. The control loop uses the timing signal and a feedback signal to generate a time error signal. The clamp generator circuit uses the time error signal to generate a clamp signal that adjusts the pulse width of the inductor switch control signal to clamp the peak current output by the flyback converter in the constant current mode.

Abstract: A cord correction circuit in a primary-side-controlled flyback converter compensates for the loss of output voltage caused by the resistance of the charger cord. In one embodiment, a correction voltage is subtracted from a feedback voltage received from a primary-side auxiliary inductor. A pre-amplifier then compares a reference voltage to the corrected feedback voltage. In another embodiment, the correction voltage is summed with the reference voltage, and the pre-amplifier compares the feedback voltage to the corrected reference voltage. The difference between the voltages on the input leads of the pre-amplifier is used to increase the output voltage to compensate for the voltage lost through the charger cord. The flyback converter also has a comparing circuit and a control loop that maintain the peak level of current flowing through the primary inductor of the converter. Adjusting the frequency and pulse width of an inductor switch signal controls the converter output current.

Abstract: Systems and methods for varying dye loads. A fluid ejection apparatus includes a reservoir and an assembly. The reservoir stores ink with a first dye load and the assembly receives the ink with the first dye load from the reservoir. To obtain ink with higher dye load, the assembly evaporates a portion of the liquid solvent in the ink to obtain ink with a higher dye load.