What is the calculation formula of SMD inductance, what is the maximum current of SMD inductor?

l=ψ/i。

The basic formula for inductance is: l= i. The formula for defining inductance is:

l=phi/i。That is, the quotient of voltage divided by the current as a derivative of time. Empirical formula:

l=（k*μ0*μs*n2*s）／l。The definition of inductance is as follows: 1. The quotient of voltage divided by the current as a derivative of time.

2. L=phi I (in a circuit, when the current flows through the conductor, an electromagnetic field will be generated, and the magnitude of the electromagnetic field divided by the magnitude of the current is the inductance). 3. The inductance is the ratio of the magnetic flux of the wire to the current that produces the alternating magnetic flux in and around the wire when the alternating current passes through the wire. 4. The inductance definition formula l= i, which means that the magnetic flux of the coil is caused by a unit of current.

The formula for calculating the inductance of an inductive device: method 1, l = ae*n2 l, where: l represents the inductance, represents the permeability of the core, ae represents the cross-sectional area of the core, n represents the number of turns of the coil, and lm represents the length of the magnetic circuit of the core.

Method 2: Empirical formula: l = (k * 0 * s * n2 * s) l, where 0 is vacuum permeability = 4 * 10 (-7). (minus seventh power of 10), s is the relative permeability of the core inside the coil, in the case of an empty coil s=1, n2 is the square of the number of coils, the cross-sectional area of the s coil in square meters, the length of the l coil in meters, and the k coefficient depends on the ratio of the radius (r) to the length (l) of the coil.

The unit of calculated inductance is Henry (h).

Chip power inductor wire diameter The formula for calculating the number of turns.

The amount of inductance of the power inductor loaded is calculated as follows: coil formula.

Impedance (ohm) = 2 * f (operating frequency) * inductance (mh), 360ohm impedance is required for setting, so:

Inductance (MH) = Impedance (ohm) 2* f (operating frequency) = 360 2* =

From this, the number of coils can be calculated:

Number of turns = [inductance * ] circle diameter (inches).

Number of laps = [ = 19 laps.

Formula for calculating hollow inductance.

The formula for calculating hollow inductance is: l(mh)=(

d--- coil diameter.

n --- number of coil turns.

d--- wire diameter.

h--- coil height.

w --- coil width.

The units are millimeters and mh, respectively.

Formula for calculating the inductance of the air core coil:

l=(coil inductance l unit: micro-hyen.

Coil diameter dunit: cm

Number of turns of the coil n unit: turns.

Coil length l unit: cm

Frequency inductor capacitance calculation formula:

L=Working Frequency: F0 Unit: MHz This question f0=125kHz=

Resonant capacitance: C unit: PF This question is proposed c=500....1000pf can be decided by the first decision, or by q

value determined. Resonant inductance: l Unit: micro-hylen.

1。For loop cores, the following formula is available: (iron).

l=n2 al l= inductance value (h).

h-dc= l n= number of coil turns (turns).

al= induction factor.

h-dc = DC magnetizing force i= passing current (a).

l= length of magnetic circuit (cm).

For the size of L and Al values, please refer to the Micrometal Comparison Table. For example, with T50-52 material, the coil has 5 and a half turns, and its L value is T50-52 (indicating that OD is inch), and its Al value is about 33NH after checking the table

l=33．(

When a current of 10A is flowed, the change in its L value can be determined by L = Lookup Table).

h-dc= l = = (after looking up the table).

You can see how much the L-value has dropped (i%)

2。Introducing an empirical formula.

l=(k*μ0*μs*n2*s)/l

Thereinto. 0 is the vacuum permeability = 4 *10 (-7). (minus seven power of 10).

s is the relative permeability of the core inside the coil, and s=1 in the case of an empty coil

n2 is the square of the number of coil turns.

s The cross-sectional area of the coil in square meters.

l The length of the coil in meters.

The k-factor, which depends on the ratio of the radius (r) to the length (l) of the coil.

The unit of calculated inductance is Henry.

1. The chip inductor is not all high-current current, as for the maximum current of the chip inductor, in fact, it depends on many factors, and the core is related to the specific case.

2. The current used in the SMD inductor on the market is mainly below 1A, and the current demand for SMD inductors in most industries is basically below 1A, and there are not many more than 1A (except for special cases).

3. The use of 2A-3A current size of the chip inductor is actually a large current. There are not many inductor manufacturers that can design and manufacture 2A-3A current size, and for factories that only provide standard inductors, they basically do not want to change the design and manufacture of high-current inductors, mainly due to the lack of professional technical support.

SMD inductors. In fact, it is also known as power inductance.

The characteristics of high-current inductors can be summed up as miniaturization, high quality, high energy storage, and low resistance. Therefore, the future development trend of chip inductors can be said to be very good. Stupidly, in this article, we still want to take a look at the little knowledge of chip inductors, and today we will talk about the problem of chip inductor current.

There are many people who ask what is the maximum current of the current of the current chip power inductorIs it better to have a larger current in a chip inductor?In response to the question of whether the larger the current of the chip inductor, the better, we have a saying:

The extremes of things must be reversed!The current of the chip inductor is certainly not as large as possible!A chip inductor acts as an electronic component on a circuit board.

Its current size must be determined according to the actual needs of the circuit board, for example, the current that can only be loaded on this circuit board, then only need to use a chip inductor with Zhongshen that can meet the current.

Next, let's look at the first question: what is the maximum current of the chip power inductor. At present, the chip power inductor current commonly used in various industries is less than 1A.

In this range, it can be regarded as a conventional type, and more than 1A is a relatively large current. The current of our high-power chip inductors can now be 2A-3A. Increasing the current of an inductor from 1A to 3A is not a very simple task.

I know a lot of people may say that it's just 1a to 3a, just adjust the parameters. But the reality is not as simple as everyone thinks.

Why do many manufacturers of inductors that do conventional current, if you want them to provide you with 2A or 3A high current inductors, they will not be willing to do it. Because there are too many technical problems involved, it is difficult to increase the inductor current from 1A to 2A or even 3A without corresponding technical support.

The maximum flow rate of a chip inductor should be between 60 and 80.

What is the maximum current of the chip inductor, I think the maximum current of the chip inductor may be five amps.

SMD power inductors, also known as chip inductors, high-power inductors, this type of inductor has the characteristics of high power, high saturation current, low impedance, and miniaturization. For example, the power supply circuit and some occasions that require large power and small volume, the main specifications and models are: CD31, CD32, CD43, CD52, CD53, CD54, CD73, CD75, CD104, CD105

The parameters of the chip power inductor are as follows:

Specification Model Specification Size (lxwxh) Inductance Rated current.

cd31 ~ 390uh ~

cd32 1uh ~ 680uh ~

cd42cd43 1uh ~ 1000uh ~ 3a

cd52 ~ 220uh ~

cd53 ~ 1000uh ~

cd54 1uh ~ 1000uh ~

cd73 ~ 470uh ~ 5a

cd75 1uh ~ 2200uh ~

cd104 10uh ~ 1000uh ~

cd105 ~1800uh ~ 6a

Please refer to the specific specifications and parameters.

There are many types of chip inductor specifications and models, and the commonly used ones are:

1. SMD power inductance.

SMD power inductors.

Some people also call chip inductors, high-power inductors, this type of inductors have the characteristics of high power, high saturation current, low impedance, and miniaturization. For example, the power supply circuit and some occasions that require large power and small volume, the commonly used models are CKO32, CKO43, CKO52, CKO53, CKO54, CKO73, CKO75, CKO104, and CKO105.

2. Chip shielding inductance.

SMD shielded inductors are mainly high current, low DC resistance, strong anti-interference ability, plus a shielding cover on the body, commonly used models are CKCH73, CKCH74, CKCH105, CKCH124, CKCH127, CKCH129

3. Multilayer inductance.

Multilayer inductors, also known as multilayer inductors, are commonly used in the form of low power, closed circuits, no interactive interference, and are suitable for high-density installation and signal processing.

Magnetic inductance. NR magnetic inductor, also known as NR inductor, is characterized by: metallizing electrodes directly on the ferrite core, strong drop impact resistance, and durability; Closed magnetic circuit structure design, less magnetic flux leakage, strong anti-EMI ability; Commonly used models are, CS252010, CS252012, CS3010, CS3015, CS4020, CS4030, CS5020, CS5040, CS6028, CS6045, CS8040 and so on.

According to the type of SMD BAI inductors, they can be divided into: wirewound DU type, laminated type, braided type and thin film DAO type inductors.

It can be divided into genera according to the type of product.

SMD inductors, power inductors, chip shielded inductors, chip laminated inductors, high-power inductors, integrated inductors and other products.

The main commonly used SMD inductor models are:

NR Magnetic Adhesive Inductor Series: NR3015-NR8060

SMD power inductor series: CD32 42 43 53 54 73 75 104 405

SMD shielded inductor series: CH73 74 105 125 127 129 1510 and 3D28 4D18 4D28 5D18 5D28 6D28 6D38 8D38 8D43

Chip laminated inductor series: 0402 0603 0805 1206

One-piece inductor series: 0503 0624 0603 0605 1005 1206

For details, refer to the Cenko inductor.

There are many types of chip inductors, and there are generally four commonly used types: chip power inductors, chip shielding inductors, laminated inductors, and NR magnetic adhesive inductors.

SMD inductors. There are actually many parameters, but the core parameters are mainly the following:

1. Electric envy inductance (L).

2. Sensory Brother Potato Bureau (XL).

3. Quality factor Q

4. DC resistance hand grinding.

5. Rated current.

The main parameters of chip inductors include inductance, allowable deviation, distributed capacitance, rated current and figure of merit.

About how to measure the inductance value of the royal patch inductance, simply put, it is to use professional testing instruments, but the specific measurement steps are relatively simple for professionals

1.Familiarize yourself with the rules (instructions) and precautions for using the equipment.

2.Turn on the power and prepare for 15-30 minutes.

3.Select the file and select Measure Inductance.

4.Hold the two clips together and reset to zero.

5.Place two clips on either end of the inductor, read the value and record the inductance.

6.Repeat steps 4 and 5 to record the measurements. There should be 5-8 pieces of data.

7.Compare multiple measurements: If the difference is not large (take the average and remember the theoretical value of the inductance, if the difference is too large, repeat steps 2-6 until the theoretical value is obtained. The inductance value is the value obtained.

The most commonly used specifications and sizes of chip power inductors are: CD32, CD43, CD54, CD75, and CD105

Package Dimensions of SMD Power Inductors:

Specification Model Specification Size (lxwxh) Inductance Rated current.

cd31 ~ 390uh ~

cd32 1uh ~ 680uh ~

cd42cd43 1uh ~ 1000uh ~ 3a

cd52 ~ 220uh ~

cd53 ~ 1000uh ~

cd54 1uh ~ 1000uh ~

cd73 ~ 470uh ~ 5a

cd75 1uh ~ 2200uh ~

cd104 10uh ~ 1000uh ~

cd105 ~1800uh ~ 6a