A hysteretic current mode buck-boost voltage regulator including a buck-boost voltage converter, a switching controller, a window circuit, a ramp circuit, and a timing circuit. The timing circuit may be additional ramp circuits. The voltage converter is toggled between first and second switching states during a boost mode, is toggled between third and fourth switching states during a buck mode, and is sequentially cycled through each switching state during a buck-boost mode. The ramp circuit develops a ramp voltage that simulates current through the voltage converter, and switching is determined using the ramp voltage compared with window voltages provided by the window circuit. The window voltages establish frequency, and may be adjusted based on the input and output voltages. The timing circuit provides timing indications during the buck-boost mode to ensure that the second and fourth switching states have approximately the same duration to provide symmetry of the ramp signal.

Hysteretic current mode buck-boost control architecture

A method for adjusting reactance includes an adjustable reactance generator including a comparator receiving an input sinusoidal waveform and outputting a square wave that retains the frequency and phase of the applied sinusoidal waveform. The reactance adjustment is generated using a power switching circuit that receives the square wave from the comparator as a control signal and outputs a square wave that retains the frequency and phase of the applied sinusoidal voltage waveform, an adjustable power supply that adjusts the amplitude of the square wave output by the power switching circuit, and an amplitude detector that controls the output level of the adjustable power supply. The power switching circuit output, when converted to a sinusoid, provides the effect of an adjustable reactance.

Method of and apparatus for generating an adjustable reactance

A method of generating pulse width modulated (PWM) signals includes receiving a coarse signal correlated to the widths of pulses to be generated in the PWM signal. Trigger signals are generated and a one-shot device is triggered in response to the trigger signals. The one-shot device generates pulses having widths correlated to the coarse signal. A control signal correlated to the widths of the pulse to be generated in the PWM signal is received and the widths of the pulses generated by the one-shot device are adjusted in response to the control signal.

Method and circuitry for generating pulse width modulated signals

A low side driver includes a first transistor coupled in series with a second transistor at a low side voltage node for a load. A capacitance is configured to store a voltage and a voltage buffer circuit has an input coupled to receive the voltage stored by the capacitance and an output coupled to drive a control node of the second transistor with the stored voltage. A current source supplies current through a switch to the capacitance and the input of the voltage buffer circuit. The switch is configured to be actuated by an oscillating enable signal so as to cyclically source current from the current source to the capacitance and cause a stepped increase in the stored voltage which is applied by the buffer circuit to the control node of the second transistor.

Current slope control method and apparatus for power driver circuit application

A transmitting device including: a modem configured to generate a baseband signal and an envelope data corresponding to the baseband signal; a supply modulator including a first switched-mode power supplier and a second switched-mode power supplier, the supply modulator configured to provide a modulated voltage to an output node based on the envelope data; and a power amplifier configured to amplify a carrier wave signal by using the modulated voltages, the carrier wave signal being associated with the baseband signal, wherein the first switched-mode power supplier includes: a pulse input node to receive a pulse signal generated in association with the envelope data; and a plurality of stages sequentially connected between the pulse input node and the output node, the plurality of stages configured to adjust the modulated voltage by filtering certain frequency band of the pulse signal, and the plurality of stages includes at least one variable impedance.

Supply modulator including switched-mode power supplier and transmitting device including the same

A hysteretic power converter constituted of: a switched mode power supply; a hysteretic comparator, a first input of the comparator arranged to receive a feedback signal providing a representation of the output voltage of the switched mode power supply and a second input of the comparator arranged to receive a reference voltage; a ramp capacitor coupled to one of the first and second input of the comparator; a current source, a terminal of the current source coupled to the ramp capacitor and arranged to drive current to the ramp capacitor; and a switchable current source, a terminal of the switchable current source coupled to the ramp capacitor, the switchable current source arranged to drive current to the ramp capacitor in a direction opposite the current driven by the current source, wherein the switchable current source is alternately enabled and disabled responsive to the output of the hysteretic comparator.

Converter with hysteretic control

A hysteretic power converter (100) constituted of: a switched mode power supply (40); a hysteretic comparator (20), a first input (FB) of the comparator arranged to receive a feedback signal providing a representation of the output voltage of the switched mode power supply and a second input (VREF) of the comparator arranged to receive a reference voltage; a ramp capacitor (180) coupled to one of the first and second input of the comparator; a current source (140), a terminal of the current source coupled to the ramp capacitor and arranged to drive current to the ramp capacitor; and a switchable current source (150), a terminal of the switchable current source coupled to the ramp capacitor, the switchable current source (150) arranged to drive current to the ramp capacitor in a direction opposite the current driven by the current source (140), wherein the switchable current source is alternately enabled and disabled responsive to the output of the hysteretic comparator (20).

Kevin Mark Smith

Papers

Converter with hysteretic control

Hysteresis control for step-down dc/dc converter