Power management integrated circuit

A power management integrated circuit (PMIC) is a multi-function integrated circuit that is used to control power distribution in an electronic device.¹ Although power management encompasses a wide range of functions, most PMIC chips include several DC/DC converters or their control mechanisms. A PMIC is often included in battery-operated devices (such as mobile phones, tablet computers, portable media players) and embedded devices (such as routers) to decrease the amount of space required for circuitry.

The term PMIC refers to a class of integrated circuits that perform various functions related to power requirements. A PMIC may have one or more of the following functions:²

• DC-to-DC conversion
• Battery charging
• Power-source selection
• Voltage scaling
• Power sequencing
• Miscellaneous functions

Power management ICs are solid-state devices that control the flow and direction of electrical power. Many electrical devices use multiple internal voltages (e.g., 5 V, 3.3 V, 1.8 V, etc.) and sources of external power (e.g., wall outlet, battery, etc.), meaning that the power design of the device has multiple requirements for operation. A PMIC can refer to any chip that is an individual power related function, but generally refer to ICs that incorporate more than one function such as different power conversions and power controls such as voltage supervision and undervoltage protection. By incorporating these functions into one IC, a number of improvements to the overall design can be made such as better conversion efficiency, smaller solution size, and better heat dissipation.³

A PMIC may include battery management, voltage regulation, and charging functions. It may include a DC to DC converter to allow dynamic voltage scaling. Some models are known to feature up to 95% power conversion efficiency. Some models integrate with dynamic frequency scaling in a combination known as DVFS (dynamic voltage and frequency scaling).

It may be manufactured using BiCMOS process. They may come as QFN package. Some models feature I²C or SPI serial bus communications interface for I/O.

Some models feature a low-dropout regulator (LDO), and a real-time clock (RTC) co-operating with a backup battery.

A PMIC can use pulse-frequency modulation (PFM) and pulse-width modulation (PWM). It can use switching amplifier (Class-D electronic amplifier).

Due to the prevalence of battery-operated mobile devices and the need for precise voltage control in modern processors, PMICs have become a critical sector in the semiconductor industry. Major manufacturers can be categorized as follows: