What is an inverter?

The inverter is a DC to AC transformer, which is actually a voltage inversion process with the converter. The converter converts the AC voltage of the power grid into a stable 12V DC output, while the inverter converts the 12V DC voltage output by the adapter into high-frequency high-voltage AC; both parts also use the more commonly used pulse width modulation (PWM) technology. The core part is a PWM integrated controller, the adapter uses UC3842, and the inverter uses the TL5001 chip. The operating voltage range of TL5001 is 3.6~40V, and it has an error amplifier, a regulator, an oscillator, a PWM generator with dead zone control, a low voltage protection circuit and a short circuit protection circuit.

Input interface part: The input part has 3 signals, 12V DC input VIN, working enable voltage ENB and Panel current control signal DIM. VIN is provided by the Adapter, and the ENB voltage is provided by the MCU on the motherboard, and its value is 0 or 3V. When ENB=0, the inverter does not work, and when ENB=3V, the inverter is in normal working state; and the DIM voltage is provided by the motherboard, and its variation range is between 0 and 5V. Different DIM values ​​are fed back to the feedback end of the PWM controller, and the current provided by the inverter to the load will also be different. The smaller the DIM value, the greater the current output by the inverter.

Voltage start loop: When ENB is high, high voltage is output to light up the backlight tube of the Panel.

PWM controller: It consists of the following functions: internal reference voltage, error amplifier, oscillator and PWM, overvoltage protection, undervoltage protection, short circuit protection, and output transistor.

DC conversion: The voltage conversion circuit is composed of MOS switch tube and energy storage inductor. The input pulse is amplified by the push-pull amplifier and drives the MOS tube to perform switching action, so that the DC voltage charges and discharges the inductor, so that the other end of the inductor can obtain AC voltage.

LC oscillation and output circuit: ensure the 1600V voltage required for the lamp to start, and reduce the voltage to 800V after the lamp starts.

Output voltage feedback: when the load is working, the sampling voltage is fed back to stabilize the voltage output of the I inverter.

Function
The inverter converts DC power (battery, storage battery) into AC power (generally 220v50HZ sine or square wave). In layman’s terms, an inverter is a device that converts direct current (DC) into alternating current (AC). It consists of an inverter bridge, control logic and filter circuit.
Simply put, an inverter is an electronic device that converts low-voltage (12 or 24 volts or 48 volts) DC power into 220 volts AC power. Because 220 volts AC power is usually rectified into DC power for use, and the role of the inverter is the opposite, hence the name. In an era of “mobility”, mobile office, mobile communication, mobile leisure and entertainment. When on the move, not only low-voltage direct current is needed from batteries or storage batteries, but also 220-volt alternating current, which is indispensable in daily life. Inverters can meet these needs.