LTC3887IUJ#PBF

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

LTC3887IUJ#PBF Application Field and Working Principle

Introduction: The LTC3887IUJ#PBF is a monolithic synchronous step-down regulator controller with an internal high-side switch and a low-side synchronous rectifier. It is designed to operate from input voltages up to 38V and provides accurately regulated outputs at a maximum current of 14 amperes at voltages from 0.8V up to 8V.

Application Field: The LTC3887IUJ#PBF is well suited for applications in portable devices requiring high power conversion efficiency, such as cellular phones, notebook computers, digital cameras, and handheld medical instruments. This device can be used in a wide variety of applications ranging from single Li-Ion battery applications, to adapters, to secondary-side applications such as USB and PoE.

Features: The LTC3887IUJ#PBF features an internal high-side switch and an internal low-side synchronous rectifier to minimize external components and reduce solution size and cost. The device operates at frequencies up to 1MHz and is programmable to either skip pulse or power-save modes to reduce the output current ripple and provide higher efficiency under light load conditions. It also features a real-time output voltage compensation algorithm providing excellent transient response.

Working Principle: The LTC3887IUJ#PBF operates as a synchronous step-down regulator and utilizes an internal high-side switch and a low-side synchronous rectifier to provide accurate output voltages with high efficiency. The input voltage is externally applied to the device, and the switching frequency is externally set using an external resistor. The main principle of operation is that the internal high-side switch is turned on when the voltage at the switches output node reaches the switch-on threshold, and then turned off when the output voltage has been regulated to the desired value. During the on time of the high-side switch, current is delivered to the output by the synchronous rectifier and the output voltage is monitored. If the output voltage is greater than the set point, the controller reduces the switch-on current, turning off sooner and thus reducing the output voltage. On the other hand, if the output voltage is lower than the set point, the controller increases the switch-on current and the output voltage is increased accordingly.

Detailed Operation: When the high-side switch is turned on, the input voltage is applied to the switch\'s output node and current is delivered to the output via the synchronous rectifier. The power flow is monitored by the sensing circuitry, which continuously senses the output voltage and compares it to the internal reference voltage. If the output voltage is greater than the reference voltage, then the controller turns off the switch sooner, thereby reducing the output voltage. Conversely, if the output voltage is lower than the reference voltage, the controller will increase the switch-on current, thereby increasing the output voltage. Finally, the low-side switch is turned on and off depending on the current sense voltage, which is the voltage across the synchronous rectifier. When the current sense voltage reaches the peak current sense voltage, then the switch is turned off.

Conclusion: The LTC3887IUJ#PBF is an efficient, monolithic synchronous step-down regulator controller designed for use in a wide range of applications from portable devices requiring high power conversion efficiency up to secondary-side applications such as USB and PoE. It uses an internal high-side switch and low-side synchronous rectifier to reduce external components and provide accurately regulated outputs. The device operates at a maximum frequency of 1MHz and is programmable to either skip pulse or power-save modes to reduce the output current ripple and provide higher efficiency under light load conditions.

The specific data is subject to PDF, and the above content is for reference