UC3842AN datasheet & circuit | pdf onsemi

UC3842AN Pinout Equivalent

1：Overview of the UC3842AN：

UC3842AN is a high-performance fixed-frequency current mode controller chip with a low pin count and simple external components, enabling precise duty cycle control. It operates over a wide voltage range and is commonly used in switch-mode power supplies to provide stable drive signals and protection features such as overcurrent and undervoltage protection, ensuring reliable system operation.

2：UC3842AN Important pin function definition:

3：Alternative model recommendation

UC3845：Similar to the UC3842AN, it has a maximum duty cycle of 100%, whereas the UC3842AN’s maximum duty cycle is approximately 50%. This makes it suitable for switch-mode power supply designs that require a higher duty cycle.

SG3842：It is a direct replacement for the UC3842AN, produced by a different manufacturer, with identical pin configurations and functions, offering excellent compatibility and widely used in switch-mode power supplies.

TL494：This is a versatile PWM control chip that supports dual-output functionality. It can operate in either push-pull mode or half-bridge mode, offering flexible features. Besides switching power supplies, it can also be used in motor control and other applications.

KA3842：Similar to the UC3842AN in terms of functionality and pin configuration, it is a common current-mode PWM controller that provides precise pulse-width modulation control and can be used in various switching power supply circuits.