Classification of matrices for long line drives

RGB and VGA are unified types of matrices that both transmit VGA signals, just engineering or transmitting RGB over long distances is better.

DVI,HDMI is an all-digital matrix It is characterized by higher clarity and quiet penetration,But the transmission distance is limited,No long line driver of the shirt and socks can be transmitted 15 meters。

Do you know what a VGA head is?

The one that can take over this head is called the VGA matrix.

1. LED power supply can be divided into two categories according to the driving mode:

a.Regulated:

1. After the voltage stabilizing circuit determines the parameters, the output is a fixed voltage, but the output current changes with the increase or decrease of the load.

2. Although the voltage regulator circuit is not afraid of open circuit of the load, it is strictly forbidden to completely short circuit the load.

3. The voltage change after rectification will affect the brightness of the LED.

4. In order to make each string drive the LED display brightness uniformly with a voltage regulator circuit, it is necessary to add a suitable resistance.

b.Constant Current:

1. The constant current drive circuit is ideal to drive the LED, and the disadvantage is that it is higher.

2. Although the constant current circuit is not afraid of short circuit of the load, it is strictly forbidden to completely open the load.

3. The output current of the constant current drive circuit is constant, while the output DC voltage changes within a certain range with the size of the load resistance.

4. The number of LEDs should be limited, because it has the maximum current and voltage value.

2. LED power supply can be divided into six categories according to the circuit structure:

1. Conventional transformer step-down:

The advantage of this power supply is that it is small in size, and the disadvantage is that it is heavy in weight and low in power efficiency, generally at 45% 60%, because the reliability is not high, so it is rarely used.

2. Capacitor step-down:

The LED power supply in this way is easily affected by the voltage fluctuation of the power grid, and the power supply efficiency is low, and the LED should not be used when flashing, because the circuit is stepped-down by the capacitor, and when it is used in flashing, due to the effect of charging and discharging, the instantaneous current through the LED is extremely large, and it is easy to damage the chip.

3. Electronic transformer step-down:

The shortcomings of this power supply structure are low conversion efficiency, narrow voltage range, generally 180 240V, and large ripple interference.

4. Resistance step-down:

This type of power supply is very inefficient and the system is less reliable. Because the circuit is stepped-down by the resistor, it is greatly disturbed by the change of grid voltage, and it is not easy to make a regulated power supply, and the step-down resistor itself consumes a large part of the energy.

5. RCC step-down switching power supply:

The advantages of this LED power supply are that the voltage regulation range is relatively wide, the power efficiency is relatively high, generally in 70% 80%, and the application is wider. The main disadvantages are that the switching frequency is not easy to control, the load voltage ripple coefficient is large, and the load adaptability is poor in abnormal situations.

6. PWM controlled switching power supply:

At present, the LED power supply designed by PWM control mode is ideal, because the output voltage or current of this switching power supply is very stable. The power conversion efficiency is extremely high, generally as high as 80% to 90%, and the output voltage and current are very stable. The LED power supply in this way is mainly composed of four parts, which are:

Input rectifier filter part, output rectifier filter part, PWM voltage regulation control part, switch energy conversion part. Moreover, this kind of circuit has perfect protection measures and belongs to a high-reliability power supply.

Mojay

LED power driver M8914 M8910

The M8914 is a single-stage buck PFC controller designed primarily for LED lighting applications. Higher efficiency is achieved by using a quasi-resonant mode to drive a buck converter. Keep the buck converter working for a constant time to achieve a high PFC.

Features: The valley switch is used to control the primary-side MOS transistor to achieve low switching loss, the primary-side current sampling reference voltage is low, the sampling resistance with a small connection resistance is connected, and the built-in high-current drive is smaller.

Low start-up current: 15 A typical.

Reliable short-circuit and open-LED protection.

Power Factor" with single-stage conversion.

Small package: SOT23-6

Product application: LED lighting.

Downlight par light.

Bulb T5, T8 tube.

It is mainly divided into two categories: AC and DC.

The output voltage and current are to be selected according to the load.

There are a lot of them online, so find them yourself.

The matrix in the graph is l

a=[l(find(l(:,3)==0),:

b=[l(find(l(:,3)==1),:

For example: l =

a=[l(find(l(:,3)==0),:

b=[l(find(l(:,3)==1),:a =b =

The matrix is actually equal to its chunked matrix, and there is no equivalence.

Multiplication requirements for tile matrices: The division of the left matrix column is the same as the division of the right matrix row.

Divide matrix a into 5*5 blocks:

b = blockproc(a, [5 5], bs) any(:)==0));Whether the block statistics are 0

s = sum(b(:) find the total.