The UC3843N is an integrated circuit (IC) component that belongs to the family of current-mode PWM controllers. It is widely used in various power supply applications to regulate the output voltage by adjusting the duty cycle of a PWM signal. The UC3843N offers several key features that make it a popular choice among electronic designers.
One of the primary features of UC3843N is its ability to operate in a wide input voltage range, typically from 7V to 35V. This versatility allows the IC to be employed in diverse power supply designs catering to different input voltage requirements. The IC also incorporates an internal start-up circuit, which enables the power supply to start smoothly without causing any voltage spikes or glitches.
In terms of control, the UC3843N utilizes a current-mode control architecture. This control method provides excellent line regulation and inherent stability benefits, making it suitable for applications that require tight voltage regulation. It employs an error amplifier to compare the feedback voltage with an internal reference voltage and generate an error signal, which is then fed into the PWM comparator.
Another notable feature of the UC3843N is its flexible oscillator. It has an external timing capacitor that can be connected to set the frequency of the PWM waveform. This allows designers to adjust the switching frequency according to the requirements of their specific application.
The IC also provides comprehensive protection features to safeguard the power supply from undesirable conditions
