How to choose a power chip?What to think of the power chip model?

In the design of the circuit, there are two common power devices, DC/DC and LDO.

1. LDO is a low -voltage differential stabilizer, or a low -voltage device, indicating that it is generally used for occasions that need to lower blood pressure. It has the advantages of low cost, low noise, and small static current.It also needs very few external components, usually only one or two bypass capacitors.

The main reason why the performance of LDO linear regulators can reach this level is that the adjustment tube is to use the P voucher MOSFET.The Pitor MOSFET is a voltage drive and does not require current, so it greatly reduces the current consumed by the device itself.In addition, the voltage drop on the P -channel MOSFET is roughly equal to the product of the output current and the pitch resistance.Due to the small turn resistance of MOSFET, the voltage drop above it is very low.

2. DC/DC means DC (to) DC (conversion of different DC power supply values). As long as this definition is in line with this definition, it can be called DC/DC converter, including LDO.But in general, the device that changes DC (to) is called DC/DC.

The DC / DC includes circuits of boosting, lowering voltage, voltage / lower voltage, and reverse equal circuits.The advantages of the DC/DC converter are high efficiency, large -current output, and small static current.With the improvement of integration, many new DC/DC converters need only a few external inductors and filter capacitors.However, the output pulses and switching of such power controllers are relatively large and the cost is relatively high.

How to select the power chip:

If the input voltage and the output voltage are very close, it is best to choose the LDO regulator to achieve high efficiency. The most important thing is the low cost.There is a summary of LDO applications for peer cows:

For example, high -demanded power noise suppression and ripple suppression products,

For example, the PCB board area is small, such as mobile phones and other handheld electronic products.

For example, the circuit power does not allow the use of electrical sensors, such as mobile phones, etc.

For example, the power supply needs to have instantaneous calibration and output self -inspection function.

For example, it is required to be a product with a low pressure drop and low power consumption,

For example, it requires products with low line costs and simple solutions.

If the input voltage and output voltage differ large, or the voltage drop is large, it is necessary to consider using the switch -type DC/DC, because the input current of LDO is basically equal to the output current. If the voltage drops too large, the LDO is consumed at LDOThe energy is too large and the efficiency is not high, so DC/DC is suitable.Although DC/DC is high -efficiency, it can output large currents, but at the same time, the output interference is large, the volume is relatively large, and the cost is slightly higher.

To sum up, you must choose DC/DC when boosting, and whether to reduce the pressure, whether to choose DC/DC or LDO. It is necessary to compare the cost, efficiency, noise, and performance.

In addition to choosing a suitable type brand, you must also select the appropriate type of power chip model according to the actual functional requirements and the application use field.Because there are many types of power chip brands now, many people are usually confused when they buy. I do n’t know how to choose for targetedness. Even at all, I do n’t know how to look at the power chip model.There are better advantages.

Points for selection of power chip:

1. Understand the characteristics of power chip model

It is actually very simple to look at the power chip model. As long as you understand the types of different brands, the characteristics of the power chip, especially the specific characteristics of this model of the power supply chip, you can judge the power chip model through some features.Targeted standards.

2. Determine through the packaging instructions

If you don't know what model is the specific model of the power chip you buy, there is no way to determine through the power chip, you can directly use the various materials such as packaging or instructions to judge, or directly consult the merchant to know the power chip you buy.What kind of model is the model, and then you can determine the specific function of the power chip of this model and the scope of application use to determine whether it meets its own application needs.