XC9111C331MR-G

PMIC - Voltage Regulators - DC DC Switching Regulators

The XC9111C331MR-G DC-DC switching regulator is an integrated PMIC (Power Management IC) that combines low-noise switching regulator and over-voltage protection circuit into a single chip. It is suitable for a wide range of applications such as powering portable/battery-operated devices and accessories, DSP core supply, and reducing ripple noise from multiple power supplies. The XC9111C331MR-G has a maximum output current of 210 mA and an adjustable output voltage in the range of 0.5V to 6V. It is housed in a tiny 8-pin MLF package, making it ideal for use in high-density designs.

Application Field

The XC9111C331MR-G is an excellent choice for powering microcontrollers, ASICs, DSPs, and other low power digital ICs and equipment. Generally, this IC is ideal for applications where low output noise, low no-load power consumption, high efficiency, and compact form factor are all needed. It can be used to power low voltage regulated components, such as analog audio visual ICs, motor control circuits, chipset power supply circuits, and other low-power digital and analog applications. The XC9111C331MR-G is also suitable for battery-driven applications, where low power consumption, low noise, and ultra-stable DC output voltage are important.

Working Principle

The basic topology of the XC9111C331MR-G is a synchronous buck regulator, which is a type of power conversion circuit. It operates by controlling the switch on and off time to convert an input voltage to a fixed, regulated output voltage. The on-off times of the switch are controlled using a pulse-width-modulation (PWM) technique, in which the on-time of the switch is varied to control the output voltage. The switch is turned on by the internal clock signal, and turns off when the driver current source reaches a certain threshold, as determined by the feedback loop. The internal clock signal is then synchronized to the output voltage to maintain regulation.

When the load is light, the XC9111C331MR-G enters its Eco-Mode, which provides low noise and low current consumption. In this mode, the output voltage is regulated by decreasing the duty cycle of the PWM signal, and increasing the minimum on-time of the switch. This ensures stable output voltage operation under light load conditions, while reducing the quiescent current to an ultra-low level.

The XC9111C331MR-G is designed to provide reliable over-voltage protection. It features an externally adjustable over-voltage protection circuit, which monitors the output voltage and shuts off the switch if the voltage exceeds the threshold. This ensures that the connected load is protected from damage due to over-voltage conditions.