NR121E

Introduction

NR121E is a DC-DC switching regulator designed to provide efficient, low-cost and low-noise step-down conversion of input voltages. This device is primarily intended for applications requiring wide input voltage range and adjustable output voltage, making it ideal for use in all kinds of electronic products and devices.

Application Field

The NR121E DC-DC switching regulator from Monolithic has become a versatile and popular solution for many power conversion applications. This device can be used in automotive, aerospace, medical and industrial electronics, as well as in consumer electronics, such as digital cameras, mobile phones, and TVs. It is suitable for applications where both high efficiency and a low noise level are paramount. It is also a viable option for small power converters, where the relatively low cost of NR121E makes it highly competitive.

Working Principle

The NR121E DC-DC switching regulator utilizes a flyback topology, in which the primary winding of the transformer is connected to the input voltage while the secondary winding is connected to the output voltage. When the switching transistor is turned on, the input voltage is applied to the primary winding, while a diode rectifies the AC output from the secondary winding and supplies the output voltage. As the switching transistor turns off, the magnetic field collapses, inducing a voltage in the secondary winding which is rectified by the diode, thus supplying the output voltage. The regulation relief of the output voltage is regulated by the control signal, which determines the duty cycle (switching period) of the switching transistor.

Output Voltage Control

The NR121E is equipped with an adjustable control signal, which enables the user to adjust the output voltage over the entire input voltage range. By manipulating the duty cycle of the switching transistor, the output voltage can be increased or decreased as needed. Additionally, a shutdown pin can be used to disable the regulator, thus achieving power savings when the device is not in use.

Protection

The NR121E DC-DC switching regulator also provides a number of protection and safety features, including output sense and current limit, thermal protection, overvoltage and undervoltage protection, as well as output short circuit protection. Together these features make the NR121E a reliable and robust regulator, capable of operating in punishing environments.

Conclusion

The NR121E is a versatile DC-DC switching regulator, designed to provide efficient and low-noise step-down conversion of input voltages. Its low-cost and wide input voltage range make it ideal for use in automotive, medical, aerospace, industrial and consumer electronics. It provides a variety of features, including adjustable output voltage, output sense and current limit, thermal protection, and short circuit protection.