There are various types of power ICs, with common characteristics including:

Low working voltage: The general working voltage is 3.0-3.6V. Some operating voltages are lower, such as 2.0, 2.5, 2.7V, etc; There are also some special purpose voltage sources with a working voltage of 5V, and a few with a voltage of 12V or 28V.

Low working current: It can range from a few milliamps to several amps, but due to the fact that the working current of most embedded electronic products is less than 300mA, power ICs with a range of 30-300mA make up a large proportion in terms of variety and quantity.

Small packaging size: In recent years, portable products have been developed using SMT devices, and power ICs are no exception, mainly including SO packaging and SOT-23 packaging, μ MAX packaging and the smallest package size of SC-70 and the latest SMD packaging make the space occupied by the power supply increasingly smaller.

Comprehensive protection measures: The new power supply IC has comprehensive protection measures, including output overcurrent limit, overheating protection, short circuit protection, and battery polarity reversal protection, making the power supply work safely and reliably, and not easily damaged.

Low power consumption and power off function: The static current of the new power supply IC is generally small, usually in the tens μ A to a few hundred μ A. Individual low-power linear regulators have a static current of only 1.1 μ A. In addition, many power ICs have the function of turning off the power control terminal (controlled by voltage level), and when the power is turned off, the IC itself consumes power at 1 μ A left and right. Due to its ability to disable some circuits, it can greatly save electricity. For example, on wireless communication devices, the receiving circuit can be turned off when in the sending state; When the signal is not received, the display circuit can be turned off.

Power supply working status signal output: Many portable electronic products include microcontrollers. When the output voltage of the power supply drops by a certain percentage due to overheating or low battery voltage, the power supply IC sends a power supply working status signal to the microcontroller to reset it. This signal can also be used to indicate the working status of the power supply (when the battery voltage is low, there is an LED display).

High output voltage accuracy: The general output voltage accuracy is between ± 2% and 4%, and many new power supply ICs can achieve an accuracy of ± 0.5% to ± 1%; And the output voltage temperature coefficient is relatively small, generally ranging from ± 0.3 to ± 0.5mV/℃, while some can reach a level of ± 0.1mV/℃. The linear adjustment rate is generally 0.05%~0.1%/V, and some can reach 0.01%/V; The load adjustment rate is generally 0.3-0.5%/mA, and some can reach 0.01%/mA.

New type of combined power supply IC: Boost DC/DC converters have high efficiency but high ripple and noise voltage, while low voltage differential linear regulators have low efficiency but minimal noise. The dual output power supply IC composed of these two can effectively solve the problems of efficiency and noise. For example, the digital circuit part uses a boost DC/DC converter power supply, while the noise sensitive circuit uses an LDO power supply. This type of power supply IC includes MAX710/711, MAX1705/1706, etc. Another example is a charge pump+LDO composition, which outputs a regulated charge pump power supply IC, such as MAX868, which can output a stable voltage adjustable from 0 to -2VIN and provide a current of 30mA; The MAX1673 stabilized charge pump power supply IC outputs the same negative pressure as VIN, and the output current can reach 125mA.