Power management integrated circuit
Power management integrated circuits (power management ICs or PMICs) are integrated circuits (or a system block in a system-on-a-chip device) for managing power requirements of the host system. Thus PMIC refers to a wide range of chips, however most include some form of electronic power conversion and/or relevant power control functions. A PMIC is often included in battery-operated devices such as mobile phones and portable media players to decrease the amount of space required.
Overview
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:[1]
- 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 have 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.[2]
Features
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).
IC manufacturers
STMicroelectronics, Intel, Marvell Semiconductor, Qualcomm, MediaTek, Freescale Semiconductor,[3] Dialog Semiconductor, Silicon Mitus,[4] Exar, International Rectifier, Intersil, Maxim Integrated Products, Linear Technology, Renesas Electronics, Rohm Semiconductor, ON Semiconductor, and Texas Instruments are some of many manufacturers of PMICs.