What Discrete Device Products are Used in the Isolated LED Driver Board?

LED has a wide range of uses, such as indicator light, display panel, display, lighting, indoor lighting and outdoor lighting. As an important part of LED products, the isolated LED driver board works in a way that you can understand.

Fig.1

The function of isolated LED driver board makes the LED system safer and more stable. It completely isolates the input and output circuits by using isolation components, usually isolation transformers or optocouplers, to ensure that there is no direct electrical connection between input and output. This product usually has electrical isolation and constant current/constant voltage control.

In constant current mode, the driving board controls the output current by adjusting the switching frequency to ensure that the LED works at a constant current. In this mode, the output voltage may be adjusted with the change of LED load. In constant voltage mode, the driving board maintains a constant voltage level by adjusting the output voltage, which is suitable for LED applications that need stable voltage.

Fig.2

An isolated LED driver board may include isolation transformer, optocoupler, diode, MOS, MCU and resistor. capacitors, inductors and other products usually have functions such as overcurrent protection, overvoltage protection and overheating protection. The LED driver board uses the rectification, switching and voltage regulation capabilities of discrete device products in its work to realize accurate control of current and voltage.

Fig.3

Taking a customer's isolated LED application as an example, the driving board is composed of rectification filter, high-frequency conversion, secondary rectification filter and control circuit. The isolated scheme is safer than the non-isolated scheme, and it has isolation inductance for the input and output of the commercial power, so the safety is very good, and it is usually realized by PWM constant current scheme.

Fig.4

In the isolated LED circuit diagram, the rectifier bridge is usually used for rectification and filtering, which is combined with inductance and capacitance filtering. In the high frequency conversion circuit, rectifier, protection diode, rectifier diode and capacitor are used to convert high frequency current into fixed amplitude voltage or fixed frequency current. The secondary rectifier and filter circuit adopts products such as secondary rectifier diodes SS110/US1J/ES1J, and cooperates with capacitors and diodes for filtering. The control circuit consists of chip and rectifier.

Table.1

As a professional discrete device manufacturer, Hottech has been deeply involved in LED application for many years, and its products have been certified by many customers, providing LED brand manufacturers with products with high reliability and high performance, and it is a quality partner of LED customers.

Fig.5