DC-DC Power Converter


The DC-DC converter accepts DC input and generates different DC voltage output. It’s often used for noise isolation and stabilizes the power systems. In most circuit design, it’s designed as the secondary power suppliers.
Switching power, with the advantages of higher efficiency, smaller dimension, lighter weight, lower power dispassion, temperature and cost, it’s now widely applied in most of the electrical devices. Linear power which consumes energy to convert power by utilizing the characteristic of certain silicon components, its advantages of simple circuit, smaller ripple and noise, higher response causes those applications requires highly stability; strictly ripple and noise are all intended to use linear power solutions. In certain case of tiny power requirement, LDO will be the one to be selected in power design as an alternative of linear power.



1. DC-DC Power circuit for SOC
According to more complex of communication equipments, the higher stability request is also getting popular. Besides traditionally -48V often be applied in most telecommunication stations, the DC input supplied to communication devices reduced down to 12V, 9V or 5V. Considering the energy saving, the silicon components also adopted low voltage supply such as 5V, 3.3V, which are the most popular ones, with the trend of low power consumption request from semiconductor industry, the 1V, 1.2V, 1.5V, 1.8V and 2.5V power source is getting more popular as well than before.
2. Battery Charger
Different from the regular switching power, the different models of batteries require different charging process, such as pre-charge, constant current charging, constant voltage charging and current cutting-off. All of them need different charging voltage and current so can make sure the charging quality and guarantee on the battery life, so the charging IC need precise voltage and current detection, certain charging IC has its own specific detecting IC to work with. Since Lithium battery is the most popular one in the market, caused most battery charge IC are supporting the Lithium batteries in regular design.
3. LED Lighting
In general power supplier is constant voltage source, the brightness of LED is varies with the current flow over it. So LED needs a stable and constant current source. The LED drivers often equipped with dimming functions, such as PWM, Analog, I2C, SPI,…etc different way of dimming control. There are many equipments need LED worked as lighting functions, such as IP CAM, Display backlight, LED projector, Vehicle head light and situation lights.
4. USB Power Delivery
The power supply defined in USB PD (Power delivery) standard provides maximum 100W power capacity as below:
Profile 1 (5V@2A, 10W),for cellar phone, digital camera, portable devices. Profile 2 (5V@2A、12V@1.5A, 10~18W),for tablet, external storage devices.
Profile 3 (5V@2A、12V@3A, 10~36W), for Ultrabook, shape transform tablet.
Profile 4 (5V@2A、12/20V@3A, 10~60W),for microUSB on high performance Notebook, All-in-one computers.
Profile 5 (5V@2A、12/20V@5A, 10~100W),for standard USB Type A/B ,Type-C connection for LCD monitor, digital TV.