ISL6526IB

ISL6526IB Application Field and Working Principle

The ISL6526IB is a DC/DC switching controller that belongs to the PMIC - Voltage Regulators - DC DC Switching Controllers category. It is designed to help manage the power in designs that require a step-up switch mode voltage regulator. The ISL6526IB is suitable for a broad number of applications, such as PCI Express Hot Plug Controllers, notebooks and servers, LCD monitors, and other various portable applications.

Features

The ISL6526IB has a wide range of features, such as a 3MHz constant frequency current mode architecture, pulse-by-pulse current limit, relay-driven protection circuit, voltage mode PWM, programmable soft-start, overvoltage protection (OVP), overcurrent protection (OCP), and thermally enhanced, low-profile surface-mount packages. It also has an integrated 1.2 Ω gate driver and a thermal shutdown protection, as well as an adjustable forced continuous conduction mode (FCCM) current limit. The ISL6526IB is the ideal option for designs that need an efficient, low RDS(on) MOSFET switch controller.

Pinout

The ISL6526IB has 5 pins, each with a specific function, as follows:

• VGATE: This is the gate driver output. It is used to control the gate of the external MOSFET.
• CS: This is the current-sense input pin. The current-sensing resistor is connected between this pin and AGND.
• FB: This is the feedback voltage input pin. It is used to detect the output voltage of the converter.
• EN: This is the enable pin. It is used to enable or disable the ISL6526IB.
• VIN: This is the supply voltage input pin. It is used to provide a regulated voltage supply to the IC.

Working principle

The working principle of the ISL6526IB is based on the voltage mode PWM technique. The oscillator in the IC generates a signal with a pre-determined frequency that is then passed through the pulse-by-pulse current limit circuit and the voltage loop amplifier. The voltage loop amplifier compares the voltage provided by the feedback voltage input pin with an internal reference voltage and adjusts the oscillator frequency until the two voltages match. This loop ensures that the ISL6526IB keeps the output voltage constant. A great advantage of this design is that any changes in the line and load conditions can be adjusted by the circuit.

Conclusion

In conclusion, the ISL6526IB DC/DC switching controller is a great option for designs that require efficient operation with a low RDS(on) MOSFET switch controller. It is suitable for a broad range of applications and features several useful features, such as a 3MHz constant frequency current mode architecture, voltage mode PWM, overvoltage protection, overcurrent protection, and an adjustable forced continuous conduction mode (FCCM) current limit.