Power management chip
The Power Management Integrated Circuits (Power Management Integrated Circuits) is a chip that is responsible for the conversion, distribution, detection and other power management responsibilities of electric energy in the electronic equipment system. It is mainly responsible for identifying the power supply amplitude of the CPU and generating the corresponding short-moment waves. Promote the subsequent circuit for power output. Commonly used power management chips include LMG3410R050[1], UCC12050[2], BQ25790[3], HIP6301, IS6537, RT9237, ADP3168, KA7500, TL494, etc.
For use
Identify the CPU power supply amplitude
Commonly used chips
LMG3410R050, UCC12050, BQ25790, HIP6301, IS6537, RT9237, etc.
basic type
Some of the main power management chips are dual in-line chips, and some are surface mount packages. Among them, the HIP630x series of chips are more classic power management chips, designed by the famous chip design company Intersil. It supports two/three/four-phase power supply, supports VRM9.0 specification, voltage output range is 1.1V-1.85V, output can be adjusted at 0.025V intervals, switching frequency is up to 80KHz, with large power supply, small ripple, and internal resistance Small and other characteristics, can precisely adjust the CPU power supply voltage.
Basic definition
A power management integrated circuit (IC) is a chip that is responsible for the conversion, power distribution, detection and other power management of electrical energy in the electronic equipment system. It is mainly responsible for converting source voltage and current into power that can be used by loads such as microprocessors and sensors.
In 1958, Texas Instruments (TI) engineer Jack Kilby invented the integrated circuit. This electronic component called a chip opened a new era of signal processing and power electronic equipment. Kilby also relied on this in 2000. The invention won the Nobel Prize in Physics. [7]
product type
The scope of power management is relatively wide, including power conversion (DC-DC, AC-DC, and DC-AC), power distribution and detection, and systems that combine power conversion and power management. Correspondingly, the classification of power management chips also includes these aspects, such as linear power chips, voltage reference chips, switching power supply chips, LCD drive chips, LED drive chips, voltage detection chips, battery charging management chips, gate drivers, load switches, Wide band gap switch, etc.
Scope of application
The application range of power management chips is very wide. The development of power management chips is of great significance for improving the performance of the whole machine. The choice of power management chips is directly related to the needs of the system, and the development of digital power management chips needs to overcome cost difficulties.
In today's world, people's lives are already a moment and cannot do without electronic equipment. The power management chip is responsible for the conversion, distribution, detection and other power management of electric energy in the electronic equipment system. The power management chip is indispensable to the electronic system, and its performance has a direct impact on the performance of the whole machine.
Improve performance
All electronic devices have power sources, but different systems have different requirements for power sources. In order to give full play to the best performance of the electronic system, it is necessary to select the most suitable power management method.
First of all, the core of electronic equipment is a semiconductor chip. In order to increase the density of the circuit, the feature size of the chip has always been developing towards a decreasing trend. The electric field strength increases linearly with the decrease of the distance. If the power supply voltage is still the original 5V, the electric field strength generated is sufficient to break down the chip. Therefore, in this way, the electronic system's requirements for the power supply voltage have changed, that is, different step-down power supplies are required. In order to maintain high efficiency while stepping down, step-down switching power supplies are generally used.
At the same time, many electronic systems also require a power supply higher than the power supply voltage. For example, in battery-powered equipment, the backlight power supply for driving liquid crystal displays, ordinary white LED drivers, etc., all need to boost the system power supply, which requires the use of boost Pressure type switching power supply.
In addition, modern electronic systems are developing in the direction of high speed, high gain, and high reliability. Small interference on the power supply has an impact on the performance of electronic equipment. This requires a power supply with advantages in terms of noise and ripple. The power supply performs processing such as voltage stabilization and filtering, which requires the use of linear power supplies.
The above-mentioned different power management methods can be realized through the corresponding power chip combined with very few peripheral components. It can be seen that the development of power management chips is an indispensable means to improve the performance of the whole machine. [8]
Selection factor
The scope of power management is relatively wide, including separate electric energy conversion (mainly DC to DC, that is, DC/DC), separate electric energy distribution and detection, and a system that combines electric energy conversion and electric energy management. Correspondingly, the classification of power management chips also includes these aspects, such as linear power supply chips, voltage reference chips, switching power supply chips, LCD drive chips, LED drive chips, voltage detection chips, battery charging management chips, and so on. The following briefly introduces the main types and applications of power management chips.
If the designed circuit requires the power supply to have high noise and ripple suppression, and requires a small PCB board area (such as mobile phones and other handheld electronic products), the circuit power supply does not allow the use of inductors (such as mobile phones), and the power supply needs to have instantaneous calibration and output The status self-checking function requires low voltage drop of the voltage regulator and low power consumption, low circuit cost and simple solution, so the linear power supply is the most appropriate choice. This power supply includes the following technologies: precise voltage reference, high-performance, low-noise operational amplifier, low-dropout regulator, and low quiescent current.
In occasions such as low-power power supply, op amp negative power supply, LCD/LED drive, etc., capacitor-based switching power supply chips are often used, which is commonly referred to as charge pump (Charge Pump). There are many chip products based on the working principle of the charge pump, such as AAT3113. This is a white LED driver chip composed of a low-noise, constant-frequency charge pump DC/DC converter. AAT3113 uses fractional times (1.5×) conversion to improve efficiency. The device drives 4 LEDs in parallel. The input voltage range is 2.7V～5.5V, which can provide about 20mA of current for each output. The device also has a thermal management system feature to protect any short circuits that occur on the output pins. Its embedded soft-start circuit prevents current overshoot during startup. AAT3113 uses a simple serial control interface to enable, turn off and 32-level logarithmic scale brightness control of the chip.
Inductance-based DC/DC chips have the widest range of applications. Applications include handheld computers, cameras, spare batteries, portable instruments, microphones, motor speed control, display bias, and color adjusters. The main technologies include: BOOST structure current mode loop stability analysis, BUCK structure voltage mode loop stability analysis, BUCK structure current mode loop stability analysis, over-current, over-temperature, over-voltage and soft-start protection functions, synchronization Rectification technology analysis, reference voltage technology analysis.
In addition to basic power conversion chips, power management chips also include power control chips for the purpose of rational use of power. Such as NiH battery intelligent fast charging chip, lithium ion battery charging and discharging management chip, lithium ion battery overvoltage, overcurrent, overtemperature, short circuit protection chip; chip for switching management between line power supply and backup battery, USB power management Chip; charge pump, multiple LDO power supply, power-on sequence control, multiple protections, complex power supply chip for battery charge and discharge management, etc.
Especially in consumer electronics. For example, portable DVDs, mobile phones, digital cameras, etc., can provide complex multi-channel power supplies with almost one or two power management chips to maximize the performance of the system.
Related advantages
The more functions and performance of electronic equipment, the more complex its structure, technology, and system are. The more difficult it is for traditional analog power management ICs to meet the overall power management requirements of the system, and the more expensive it is. The core of the digital controller is mainly composed of three special modules: anti-aliasing filter, analog-to-digital converter (ADC) and digital pulse width modulator (DPWM). In order to achieve the same performance indicators as the analog control architecture, it is necessary to have high resolution, high speed and linear ADC and high resolution, high speed PWM circuit design. The ADC resolution must be able to meet the range where the error is less than the allowable variation of the output voltage. The smaller the required output voltage ripple, the higher the resolution requirement of the ADC. At the same time, because anti-aliasing filters and pipelined or SAR analog-to-digital converters will introduce loop delays, we urgently need high-sampling-rate analog-to-digital converters. Analog controllers have inherent limitations on the possible pulse widths that can be generated, while DPWM can generate discrete and limited sets of PWM widths. From the perspective of output under steady state, only one set of discrete output voltages is possible. Since DPWM is a part of the feedback loop, the resolution of DPWM must be high enough so that the output does not display the well-known limit cycle value. The minimum number of digits required to not display any limit value depends on the topology, output voltage and ADC resolution. At the same time, the loop stability of the system is adjusted by PI or PID controller.
Future trend
In the future, power management chips have broad prospects. Through the development of new processes, packaging and circuit design technologies, there will be more outstanding devices that can increase power density, extend battery life, reduce electromagnetic interference, enhance power and signal integrity, and improve system safety. Help engineers around the world achieve innovation.
