LTC3834IFE#PBF

LTC3834IFE#PBF application field and working principle

Introduction

The LTC3834IFE#PBF is a step-down low-noise DC/DC synchronous switching regulator. It integrates very low RDS(ON) power MOSFETs, wide supply voltage range from 2.85V to 6V, and output voltage range from 0.6V to 5.5V. It is able to support up to 17A continuous output current. This device has user-definable slope compensation for better transient response. It is also designed for high-efficiency operation with very low operating current and low quiescent current. The LTC3834IFE#PBF is ideally suitable for applications such as processor power systems.

Application Field

The LTC3834IFE#PBF is used in those applications that require a low-noise and high-efficiency DC/DC synchronous switching regulator. The device is ideal for processors, FPGAs, ASICs, telecom systems and all kinds of portable devices. It can support up to 17A continuous output current while keeping high efficiency. The adjustable output voltage ranges from 0.6V to 5.5V, together with the wide supply voltage range, enable the device to offer a great flexibility.The wide range of output voltage from 0.6V to 5.5V makes this device work properly with different processors and ASICs. It can also provide power for numerous low power systems which is beneficial for extending device\'s battery life and reducing total system cost. The device also integrates very low RDS(ON) power MOSFETs, meaning it will have very low conduction losses, thus increasing the efficiency. Moreover, the device has built-in non-latching current-limit protection, thermal shutdown protection and frequency synchronization features.

Working Principle

The LTC3834IFE#PBF has an integrated synchronous MOSFET driver which is ideal for fast switching between synchronous power modes efficiently at high efficiency and low EMI noise. At the same time, it can convert the input voltage to output voltage with the help of pulse-width modulation (PWM) control circuit.

The PWM operation is based on the concept of switching ON and OFF power devices to regulate the voltage across the input and output. Two loop features are built into this device to ensure a smooth transition and stable operation. The voltage loop on the output side is used to maintain the proper voltage by adjusting the duty cycle of the power switch, making sure the output voltage follows the commanded level. On the other hand, the current loop helps to ensure continuous current through the device without any overshoot.The output voltage and the current sense amplifier work together to provide a voltage loop. The voltage loop is used to adjust the duty cycle of the MOSFET switch which will then keep the output voltage at its commanded level. Each sense amplifier is capable of sensing the voltage or current profile of the MOSFET switch and apply the appropriate control signals.The device also has a slew rate control feature which regulates the rate of change of the output voltage. The slew rate control improves the transient response, making sure that the voltage remains within the regulation loop.The device also provides frequency synchronization feature which allows synchronizing to other devices within the system. This improves the EMI performance by synchronizing the PWM output to the switching frequency of other devices.

Conclusion

The LTC3834IFE#PBF is a step-down low-noise DC/DC synchronous switching regulator. It integrates very low RDS(ON) power MOSFETs, wide supply voltage range from 2.85V to 6V, and output voltage range from 0.6V to 5.5V. It is able to support up to 17A continuous output current which makes it suitable for a plethora of applications. It also has user-definable slope compensation which gives better transient response, very low operating current, low quiescent current and frequency synchronization feature.