Design Of An LDO Chip Suitable For DDR Power Supply

With the development of high and new technology,the level of semiconductor technology has improved,and the internal integration of the chip has been greatly improved compared with the past.For the entire chip,the cost reasons make it impossible to power each internal module individually.The current popular solution is that the chip uses a unified power supply port,which requires higher stability and load capacity of the power supply chip.Among various power products,LDO（Low Dropout Regulator）is widely used in various electronic products due to its excellent noise performance and stability^[1].At present,LDO chips from large foreign manufacturers are favored by domestic enterprises due to their high performance and high reliability.However,due to the impact of the current international environment,foreign companies have imposed blockades on China from various parties such as technology and products,which has seriously hindered the progress of domestic production and scientific research.In order to improve the current predicament,some scholars have suggested that it can be responded by domestically replacing foreign excellent products.From this perspective,this article studies the LDO chip and combines the specific application scenarios of DDR power supply to design an LDO chip with both current source and current sink functions.Based on the research literature,and combined with the CSMC 0.5μm Double Poly Triple Metal Mixed Signal process,an LDO chip was designed.This chip contains reference module,bias module,enable module and driver module,etc.It has the following important features:1.It can provide a minimum VDDQ of 1.35V,which can meet DDR applications without external resistors,and is compatible with DDR2,DDR3,DDR3L,etc.Product application;2.VREF port can be used as external voltage bias;3.Enable and temperature protection module to ensure the stable operation of the chip;4.Current source and current sink provide a maximum current of 1.5A,which can meet the needs of various application environments.Finally,the chip test verification was completed.The experimental results prove that the chip designed this time can meet the requirements of domestic substitution and has good performance.