Abstract: A PFM-type voltage regulator circuit converts an unregulated input voltage into a regulated output voltage using a first transistor controlled by a pulse control circuit and a second transistor controlled by a linear regulator circuit. The linear regulator circuit controls the second transistor when the regulated output voltage falls to a predetermined minimum target voltage level, thereby maintaining the regulated output voltage at the minimum target voltage level. The pulse control circuit detects the current passing through the second transistor, and in response generates a pulse signal having a predetermined duration that fully turns on the first transistor. The voltage through the first transistor is converted to an increasing inductor current that refreshes the regulated output voltage to a maximum target voltage level. When the pulse signal ends, the regulated output voltage again begins to fall toward the predetermined minimum target voltage level, and the cycle is repeated.

Abstract: A comparator circuit having improved operational characteristics. A predetermined voltage drop device is provided, such as an exemplary embodiment Schottky diode, having an anode connected to circuit power supply voltage and an output stage of the comparator and a cathode connected to an input stage of the comparator. The predetermined voltage drop device effects a lowering of the power supply voltage for the output stage bias between said power supply voltage and said common voltage. This reduces the required swing of the output stage drivers during a comparator input signal transition and reduces propagation delay of said comparator.

Abstract: A switching regulator integrated circuit for controlling first and second switches in a hysteretic mode using a zero or very low equivalent series resistance (ESR) capacitor includes an integrated circuit package housing a switching regulator semiconductor chip, a first package lead on the integrated circuit package receiving the regulated output voltage and a second package lead to be coupled to a zero or low ESR capacitor of the LC filter. The first package lead may be connected to a first bond pad of the semiconductor chip using a first bond wire. A second bond wire connects the second package lead to the first package lead, or to the first bond pad, or to a second bond pad electrically shorted to the first bond pad. The capacitor is thus electrically coupled to the regulated output voltage and the second bond wire provides series resistance to the capacitor.

Abstract: A comparator circuit having improved operational characteristics. A predetermined voltage drop device is provided, such as an exemplary embodiment Schottky diode, having an anode connected to circuit power supply voltage and an output stage of the comparator and a cathode connected to an input stage of the comparator. The predetermined voltage drop device effects a lowering of the power supply voltage for the output stage bias between said power supply voltage and said common voltage. This reduces the required swing of the output stage drivers during a comparator input signal transition and reduces propagation delay of said comparator.

Abstract: Describe is a device for a multiplexing, output current-sensed, boost converter circuit which may be used as an LED driver. A boost converter LED driver circuit using a single set of passive external LC components for controlling the current through, and thus the output of, one and more than one bank of LEDs. The present invention allows for regulated current in one and more than one bank of LEDs by sensing current in the controller. The output voltage of a switcher adjusts it's level automatically until the current to the LEDs is set to the desired LED threshold requirement.

Abstract: The present invention provides an apparatus and method for improving the accuracy of circuits. The apparatus includes a replicate circuit and a trim determination circuit. The trim determination circuit includes a measurable circuit element and determines the state of the measurable element. The replicate circuit includes a replicate circuit element which has similar electrical characteristics as the measurable element, and is configured to aid in determining an adjustable test current. The trim determination circuit generates a test current which is proportional to the adjustable test current. The test current is passed through the measurable element such that a first voltage drop occurs across the measurable element. A measured current is generated at a current level dictated by the voltage drop across the measurable element, such that the state of the measurable element is determined by the difference between the measured current and a scaled reference current.

Abstract: An electrostatic discharge protection device connected in parallel with a trim-diode turns on during an electrostatic discharge event and conducts substantially all the current therefrom, yet remains inactive during diode trimming. An electrostatic discharge protection “snap-back” type device effectively turns on, diverting the electrostatic discharge current flow away from the trim-diode. Various exemplary embodiments are shown in both CMOS and Bi-CMOS technologies.

Abstract: The invention is an improved implementation of an active-RC polyphase band-pass filter with transconductor cross-coupling between filter sections. The polyphase filter has first to fourth inputs, first to fourth outputs, two filter sections, and a block of transconductor pairs. The four input signals to the polyphase filter succeed one another in phase by 90 degrees. The two filter sections have reactances comprised of active balanced operational amplifiers with matched capacitors in their feedback loops. The block of transconductor pairs is coupled between corresponding reactances of each filter. The transconductance of each transconductor pair is set as the product of a desired radian center frequency and the capacitance of the corresponding matched capacitors. In the preferred embodiment, the transconductors are Gm cells and the transconductance of at least one Gm cell is field adjustable.