LT1339IN#PBF

LT1339IN#PBF Application Field and Working Principle

Introduction

LT1339IN#PBF is a monolithic integrated circuit specially designed by Linear Technology which is used as a Pulse Width Modulation (PWM) control circuit, featuring integrated high-side and low-side MOSFET drivers. It is especially suitable for low-voltage, low-current DC-to-DC switching regulators and switching controller applications.

Application Field

In switching regulator applications, LT1339IN#PBF is capable of generating pulse width modulated output voltage and is able to achieve current mode control by providing gate drive for power MOSFET devices. With external components, feedback and current-sense components, this device can be used as a DC-to-DC synchronous buck converter from 4V to 15V. It can be employed as a general purpose DC-to-DC converter providing output voltages from 1V to 6V.

Additionally, due to the high side and low side gate drive that the device provides, it is also suitable for high voltage DC-to-DC converter applications. It is capable of producing dual multiple output voltages in such applications. It is also an ideal choice for numerous other regulating and control applications such as adjustable current source, fixed current source, and programmable current source.

Working Principle

The working principle of the LT1339IN#PBF is based on the Pulse Width Modulation (PWM) technique. This technique works based on the amplitude of a triangle waveform and comparing it to a reference voltage. The duty cycle of the output signal is regulated based on the comparison between the two signals. The LT1339IN#PBF is designed in a way that it can produce accurate output voltages, even in applications with input voltages that vary significantly.

To regulate the output voltage of the switching regulator, the device has an on-chip error amplifier that constantly compares the reference voltage to the feedback voltage. When the feedback voltage is greater than the reference voltage, the error amplifier reduces the output duty cycle, which in turn reduces the output voltage. On the other hand, when the feedback voltage is lower than the reference voltage, the error amplifier increases the duty cycle, thus increasing the output voltage.

The device also has two integrated MOSFET drivers which act as the interface between the output switches and the control logic. This allows the controller to switch the power MOSFETS on or off based on the duty cycle of the output signal, thus providing the desired output voltage.

Conclusion

The LT1339IN#PBF from Linear Technology is a state-of-the-art device specially designed for applications related to pulse width modulation and comparison. It is highly suitable for applications related to DC-to-DC switching regulators and controllers. With its highly reliable integrated MOSFET drivers, it is able to provide accurate and stable output voltages even under varying input voltages.