1. Pay attention to the maximum value of output current: this is a very critical parameter, the current used exceeds the maximum output current of LDO, then the voltage is unstable, and the system will fail.
LDO limit parameters: The output current is considered according to the 2/3 criterion. The maximum current consumed by the entire system should not exceed 2/3 of the LDO output current. Assuming that the maximum current consumption of the whole system is 50mA, it is proposed that the maximum current demand of the LDO is 50*3/2=75mA.
2. Pay attention to the heat dissipation ability and power consumption of the package: When selecting electronic components, the smaller the scale, the better, but it is necessary to consider whether the heat dissipation capacity and power consumption of the package scale meet the planning requirements.
Heat dissipation and power consumption meter: Since the input voltage is high and the output voltage is low, the LDO itself has to accept a certain voltage difference, and the larger the voltage difference, the greater the heat generation. If the heat is too high and the temperature is high, the LDO will burn out!
For example, if the input voltage is 30V, the output voltage: 5V, and the operating current is 10mA, then the power received by the LDO = (30-5) * 10mA = 0.25W. The above heat dissipation and power consumption table shows that the power consumption of SOT23-5 is 0.2W, assuming that the LDO of SOT23-5 package is selected, then the product you plan is unreliable, and the LDO will simply burn out! The operating voltage of the product plan mentioned above was 12 V, but the sample burned out when the test was performed with a 24 V voltage. Due to the increased dropout voltage, the power consumption exceeds the acceptance capacity of the SOT23-5 package. The results burned out the LDO!
Power consumption advocates using the 1/2 criterion to select the LDO package, assuming that the power that the LDO needs to accept is 0.25W, then the package with 0.5W power consumption should be selected! If the real situation does not meet the 1/2 criterion, the PCB should increase the heat dissipation area. In the case of relatively high power consumption, it is necessary to install a heat sink for the LDO.
3. Pay attention to the voltage drop of LDO: When choosing LDO, you must pay attention to the voltage drop parameters, assuming that the voltage drop is not good, the output voltage will be unstable. The pressure drop requirements of each LDO may be different, and you need to read the specifications clearly. Acknowledging compliance with planning requirements.
LDO electrical characteristics: The LDO in the above picture has a voltage drop requirement of 2V. It is clarified that the input voltage must be 2V higher than the output voltage in order to operate stably. Suppose the output voltage requirement is 5V, but the input voltage is only 6V, then the output voltage is not 5V.
4. Pay attention to quiescent current: quiescent current refers to the current consumed by LDO operation itself. Especially for battery-powered products, it is necessary to use an LDO with a lower quiescent current to improve the standby time of the product!
The fundamental characteristics of LDO: pay attention to the filter capacitance at the input and output ends, the filter capacitance required by each LDO will also be different, and the planning time should refer to the requirements of the specification to select the appropriate capacitor
LDO application circuit: If a capacitor with too small capacitance is selected, the output voltage may be unstable or the ripple may be relatively large. Assuming that the input power ripple itself is relatively large, it is advisable to use larger capacitors for the input and output terminals. The withstand voltage value of the capacitor also needs to be noted, and the 2x criterion is generally used to select. Assuming that the input voltage is 24V, it is best to choose a capacitor with a withstand voltage of 50V, assuming that the withstand voltage value is not really 2 times or less than 1.5 times. Otherwise, the product is unreliable.
|
More on that
|
Delixi leakage circuit breaker identification method
1. Appearance
Genuine Delixi switch shape is more fashionable, looks elegant and beautiful, and the surface is neat, impact resistance is relatively strong, will not briefly crack or yellow.
And most imitations will turn yellow after a period of use...
|
|
Delixi linear and switching regulators introduced
01. What is a linear voltage regulator?
A linear regulator uses a transistor or FET operating in its linear region to subtract the excess voltage from the input voltage of the application to produce a conditioned output voltage.
The so-called voltage drop voltage means that the voltage regulator maintains its output voltage at its ...
|
|
The main factor affecting the poor heat of the instrument - Delixi
The operation of differential thermal analysis is simple, but in practical work, it is often found that the same sample is measured on different instruments, or different samples are measured on the same instrument, and the results of the differential thermal curve of industrial electrical appliances are different. The high temperature, shape, area, and size of the peaks will all change. ...
|
|
An integral part of the electrical control system - Delixi
The electrical control system is generally called the secondary control loop of electrical equipment, different equipment has different control loops, and the control methods of high-voltage electrical equipment and low-voltage electrical equipment are also different. Specifically, an electrical control system refers to a combination of several electrical components that are used to complete the operation of a certain ...
|
|
Delixi occasion to choose the inverter
We need to ensure that the capacity of the inverter is matched. First of all, according to the nature of the load, the correct selection of the type of inverter.
When selecting the inverter, the current value of the actual motor should be used as the basis for the selection of the inverter, and the rated power of the motor can only be used as a reference. Secondly, the output of the inverter should be fully considered ...
|
|
The cause of the abnormality of the motor controlled by the inverter
The first method is that you can analyze what the cause is according to the condition displayed on the inverter, such as whether the faulty code appears normal, whether there is still running code or not, and still nothing appears (in the case of input power), which means that there is a rectification problem. If you're on standby...
|
|
Delixi circuit transformation attention to detail
1. If strong electricity and weak electricity are to be separated by a long distance from the horizon walking line, the interval should generally exceed 30 cm to prevent disturbance and be interspersed with each other.
2. In order to facilitate the future line change, the PVC pipe must be cut down and straightened as much as possible.
|
|
The difference between Delixi voltage regulator SBW and SJW
What is the difference between Delixi voltage regulator SBW and SJW, which is better?
Customer Question:
I maintain an uninterruptible power supply and a computer server, and the whole community shares a transformer, so the voltage fluctuation may be greater during the day and at night.
|
|
How to change the original parameters of the inverter and re-set - Delixi
The inverter has many set parameters, each of which has a certain selection range. In the process of use, it is often encountered that the inverter cannot operate normally due to improper parameter settings. Therefore, the relevant parameters must be corrected.
...
|
|
The scope of use of Delixi universal inverter
A universal inverter is an electronic device used to control the speed of an electric motor, which can change the speed of the motor according to the needs and achieve higher production efficiency and energy savings. The general-purpose inverter has a wide range of application scales and can be used for various types of motors, including communication motors, direct motors, ...
|
|
Delixi inverter parameter setting method
P0.00: Set to G type (constant torque load type).
P0.01: Set to 1 fundamental efficacy model.
P0.02: Set to 1V/F control.
P0.03: Set to 0 keyboard control.
P0.04: Set to be given by the external terminal for multi-segment commands.
...
|
|
Introduction of molded case circuit breaker - Delixi
Delixi plastic case circuit breaker is also called equipment circuit breaker, the external contact of the grounding terminal, arc extinguisher, tripper and operating organization are installed in a plastic shell. Auxiliary contacts, undervoltage trippers, parallel trippers, etc. Most of them are modular, very compact in structure, and generally do not consider maintenance ...
|
|
Delixi uses three-phase regulators need precautions
1. If the fuse is burned out, please approve the load equipment as soon as possible, make repairs in time, and restore power;
2. If you use a fixed amount of fuse, please use a regular line, and do not match it at will, so as not to cause ...
|
|
Delixi electrical components circuit breaker introduction
What is a Circuit Breaker? What is the function of a circuit breaker? How to choose the right circuit breaker in the work? The circuit breaker is what we often call an air switch. Just like a dam that controls the release of water, when the sluice gate is opened, the flow of water is continuous, and when the sluice gate is lowered, it blocks the flow of water.
...
|
|
The basic knowledge of Delixi switching regulators
1. What is a switching regulator?
Switching regulator, English (regulatior), some people call it a regulator, a voltage regulator source. To achieve voltage regulation, it is the demand control system (negative feedback), from the automatic control theory, we know that when the voltage rises through negative feedback to reduce it, ...
|
|
The 2016 Delixi Electric Construction Industry Summit was successfully held
2016 is the first year of the "13th Five-Year Plan", with the adjustment of China's economic structure, the construction profession is also changing. On September 8th, with the theme of "riding the wind and waves, building the future together", the Delixi Electric Construction Career Summit opened in Qingdao, the "International Sailing Capital". The summit ...
|
|
Delixi spare parts replacement cycle description
1. Cooling fan (2-3 years)
As long as the inverter is in use, the cooling fan has always been running, so the cooling fan is generally the shortest service life of the accessories, generally after the use of the cooling fan for 2-3 years, the bearings, balls, motors, etc. of the fan are seriously worn, and they need to be replaced.
|
|
Circuit breaker tripping conditions and solutions - Delixi
1. The problem current reaches or exceeds the set operating current value.
2. The problem current continues to arrive at the set time of action.
Therefore, it is necessary to ensure that the Delixi circuit breaker will not trip beyond its liquid level. Current setting ...
|
|
Delixi DZ47LE C40 air switch introduction
The general leakage circuit breaker is wired using the principle of outgoing wire under the progressive line, only need to distinguish the phase line and the zero line, between, the zero line is marked with N on the right, and the incoming and outgoing lines are the same.
Delixi DZ47LE C40 ...
|
|
Ways to reduce the number of inverter repairs - Delixi
Inverter is a very ubiquitous equipment in modern workshops, this is a new type of equipment, the price is very noble, and the price of inverter repair is also very expensive, so in the process of using inverter, pay attention to the use of inverter, on the one hand, inverter, delay inverter ...
|
|
Contact
working hours
