A power supply with duty cycle limiting circuit includes a conversion circuit, a drive circuit, a control unit, and a duty cycle limiting circuit. The duty cycle limiting circuit converts a control signal into a control voltage, and determines whether a power switch of a power supply is turned off according to the control voltage and a threshold voltage to limit a duty cycle of the power switch.

A control circuit of an image forming apparatus outputs a pulse signal. A clock signal generation circuit generates a clock signal, based on the pulse signal. A pulse signal conversion circuit generates a pulse conversion control signal of a voltage value associated with a duty ratio of the pulse signal. An AC voltage generation circuit generates an AC voltage of a frequency based on the clock signal. Either the AC voltage generation circuit or a DC voltage generation circuit generates a voltage whose amplitude or voltage value increases as a voltage value of the received pulse conversion control signal increases, and whose amplitude or voltage value decreases as a voltage value of the pulse conversion control signal decreases.

A control circuit of an image forming apparatus outputs a pulse signal. A clock signal generation circuit generates a clock signal, based on the pulse signal. A pulse signal conversion circuit generates a pulse conversion control signal of a voltage value associated with a duty ratio of the pulse signal. An AC voltage generation circuit generates an AC voltage of a frequency based on the clock signal. Either the AC voltage generation circuit or a DC voltage generation circuit generates a voltage whose amplitude or voltage value increases as a voltage value of the received pulse conversion control signal increases, and whose amplitude or voltage value decreases as a voltage value of the pulse conversion control signal decreases.

An aerosol delivery device is provided that includes a power source, a heating element, a switch coupled to and between the power source and the heating element, and processing circuitry coupled to the switch. The processing circuitry outputs a PWM signal during a heating time period to cause the switch to switchably connect and disconnect the output voltage to the heating element to power the heating element. The processing circuitry outputs a pulse of known current to the heating element, and measure voltage across the heating element, between adjacent pulses of the PWM signal. And the processing circuitry calculates the resistance of the heating element based on the known current and the voltage, calculates the temperature of the heating element based on the resistance, and adjusts a duty cycle of the PWM signal when the temperature deviates from a predetermined target.

An aerosol delivery device is provided that includes a power source, a heating element, a switch coupled to and between the power source and the heating element, and processing circuitry coupled to the switch. The processing circuitry outputs a PWM signal during a heating time period to cause the switch to switchably connect and disconnect the output voltage to the heating element to power the heating element. The processing circuitry outputs a pulse of known current to the heating element, and measure voltage across the heating element, between adjacent pulses of the PWM signal. And the processing circuitry calculates the resistance of the heating element based on the known current and the voltage, calculates the temperature of the heating element based on the resistance, and adjusts a duty cycle of the PWM signal when the temperature deviates from a predetermined target.

A control circuit of a power converter includes a sensing circuit, a ramp signal generation circuit and a PWM circuit. The sensing circuit, coupled to an output circuit, provides a current sensing signal. The ramp signal generation circuit includes a transient circuit and a signal generation circuit. The transient circuit receives the current sensing signal and generates a variable reference voltage. The signal generation circuit provides a ramp signal according to the variable reference voltage. The PWM circuit provides a PWM signal to the output circuit according to the ramp signal. When current sourcing occurs, it continues for a first default time. A transient state during current sourcing continues for a second default time less than first default time. The variable reference voltage is changed from a default value to an adjusted value during the second default time and restored to the default value after the second default time.

A color correction device includes a computation engine including a processor and a memory coupled to the processor. The computation engine is configured to receive reference color data. A software application stored in the memory and configured to compute adjustment values needed to achieve the reference color data from a target color. An output configured to output color corrected signals to light emitting diodes (LEDs) to achieve a reference color associated with the reference color data from the target color of the LEDs.

A color correction device includes a computation engine including a processor and a memory coupled to the processor. The computation engine is configured to receive reference color data. A software application stored in the memory and configured to compute adjustment values needed to achieve the reference color data from a target color. An output configured to output color corrected signals to light emitting diodes (LEDs) to achieve a reference color associated with the reference color data from the target color of the LEDs.

An example image forming apparatus includes a fan, a fan driver to drive the fan, a switching controller, and a processor to output a pulse width modulated (PWM) control signal to control the fan driver. The switching controller may include a smoothing circuit to receive the PWM control signal output from the processor and convert the PWM control signal to a direct current signal, a comparator to compare a value of the direct current signal with a reference value and output a switch control signal, and a switch to provide power to the fan driver based on the switch control signal output from the comparator.

An example image forming apparatus includes a fan, a fan driver to drive the fan, a switching controller, and a processor to output a pulse width modulated (PWM) control signal to control the fan driver. The switching controller may include a smoothing circuit to receive the PWM control signal output from the processor and convert the PWM control signal to a direct current signal, a comparator to compare a value of the direct current signal with a reference value and output a switch control signal, and a switch to provide power to the fan driver based on the switch control signal output from the comparator.