LED display HJ070IA - 02 d

New LED light source is a great variety of products, but the commonality is must use the low voltage dc power supply and a single device and switching circuit must be used when using the utility. For different usage, the technical implementation of LED power supply converter, there are different solutions.
According to the height of the power supply voltage, the LED driver can be divided into three types: one is powered by batteries, mainly used in portable electronic products, drive in the small power and power white LED. Two is greater than 5 power supply, regulated power supply or battery power supply, such as blood type, can lift pressure type DC a few (converter; 3 it is directly by the mains (110 v or 220 v) or the corresponding high voltage direct current (DC), such as} 40 ~ 400 v power supply, it is mainly used for camel high-power white LED, such as step-down DC/DC converter.
1, the battery power drive solutions
Normally the battery power supply voltage from 0.8 V to 1.65 V for led display such low-power lighting devices, it is a common usage, this method is mainly suitable for portable electronic products, white led driver in the small power and power, such as led flashlight, led emergency lamps, energy-saving lamps, etc. Given the likely work with section 5, battery, must have the minimum volume, so the best technical solution is charge pump boost converter, if use booster type DC (zhuang converter or booster type converter (or lifting pressure type) of charge pump, a few for the use of "circuit drive.
2, voltage gao gan and drive solutions
Voltage is higher than 5 low-voltage power supply scheme of using special regulated power supply or battery power supply, for the LED power supply voltage is always higher than that of LED tube pressure drop, which is always greater than 5 v, such as 6 v, 9 v, 12 v, 24 v or higher. In this case, mainly by the regulated power supply or battery power supply, used to drive the LED lamp. This kind of power supply scheme to solve the problem of good power step-down, typical applications have solar lawn lamp, solar garden lights, the lights of the vehicle system and so on.
3, directly from the mains or high voltage direct current (dc) power supply drive solutions
This solution directly from the line (100 v or 100 v) or the corresponding high voltage dc power supply, high power white LED lamp is mainly used for driver. Grid driver is a most valuable way of power supply, LED lighting application is the development direction of LED lighting to popularize and apply.
When using a grid drive LED to solve the problem of depressurization and rectification, have higher conversion efficiency, small volume and low cost. In addition, should solve the problem of security isolation. Considering the impact on the grid, but also solve the problem of good electromagnetic interference and power factor. For medium and small power LED, the circuit structure is the best isolation type single-ended flyback. For the application of high power, bridge type conversion circuit should be used.
For the LED driver, the main challenge lies in the nonlinear of LED display. This is mainly embodied in the LED forward voltage changes with current and temperature, different LED forward voltage of the device will have differences, LED color "point" will drift with the current and temperature, and the LED must work within the scope of the regulations, so as to realize reliable work. The LED driver is the main purpose of limiting current under the working conditions, and whatever input conditions and the forward voltage changes.
For LED drive circuit, in addition to constant current steady flow, and other key requirements. LED dimming, if needed, for example, you will need to provide the PWM, and used for the typical LED dimming PWM frequency is 1 ~ 3 KHZ. In addition, the LED drive circuit of power handling capacity must be sufficient, and powerful, can withstand a variety of fault conditions, and easy to implement. It is worth mentioning, because the LED in the most appropriate electrical flow has been won't drift.
On the choice of led display driver program, used to think that there are the inductance of the DC/DC booster type in recent years, the charge pump can output current of the driver himself up from A few hundred ma 1.2 A up and down, as A result, the output of the two types of chi actuator.