Patent ID: 12238831

DETAILED DESCRIPTION

InFIG.11, a lighting apparatus includes a light source plate601, LED modules602and a driver module603.

The multiple LED modules602may include multiple types of LED modules. These LED modules may include multiple types of LED modules, each type with a different light parameter, e.g. color temperature, color, color rendering index. Each LED module may include a lens, a LED chip, a fluorescent layer covering the LED chip or have other configuration, e.g. a light strip style light source. In some other embodiments, these LED modules may be the same.

FIG.12illustrates a sectional view of a light source plate. InFIG.12, the light source plate includes a substrate layer703, a wiring layer702and a protection layer701. The wire layer702may include patterned wires for electrically connecting components, e.g. LED modules to driver components.

The substrate layer703is made of metal material, e.g. zinc or aluminum alloy.

A thickness of substrate layer703is larger than ten times a total thickness of the wiring layer702and the protection layer701. In some embodiments, there is an additional insulation layer between the wiring layer702and the substrate layer703.

InFIG.12, the LED modules704are disposed on a top side705of the light source plate.

The driver module706is also disposed on the top side705of the light source plate.

Specifically, the LED modules704and the driver module705are placed on the same light source plate.

The LED modules704and the driver module706are electrically connected via the wiring layer702.

The driver module includes an AC-DC converter801, a regulator802, a controller804, a current source803and an oscillation wave removal circuit805.

The controller804controls the current source803to generate driving currents to the LED modules805.

The oscillation wave removal circuit805is coupled to the AC-DC converter801for suppressing a sudden abnormal peak voltage from the AC-DC converter801.

For example, under experiments, it is found that there are often ringing signals caused by the structure of the DoB (Device on Board) design if a metal plate is used for holding the driver circuits and the LED modules. Such ringing signals has some types of oscillation cycles and may cause component damages or affect light output patterns.

In some embodiments, the sudden abnormal peak voltage is an oscillation wave caused by a leakage current from the substrate layer.

In some embodiments, the substrate layer is used as a ground for coupling to the driver module. Ground, in the context of electrical and electronic systems, refers to a reference point or a conducting connection that serves as a common return path for electric currents. One of the primary reasons for connecting an LED light device to ground is safety. In the event of a fault or short circuit in the device, excess current may flow to the ground, providing a low-resistance path for the current to dissipate. This can prevent electric shocks to users and protect the device from damage.

Ground may also serve as the common reference point for voltages in the circuit. All voltage measurements are taken with respect to ground. Without a well-defined ground, it would be challenging to make accurate voltage measurements and maintain consistent circuit behavior.

Grounding may also help protect electronic components from Electrostatic Discharge (ESD). When someone touches an electronic device, static electricity can build up in their body. If they touch a sensitive component, the discharge could damage or destroy it. Grounding provides a path for this static charge to safely dissipate, protecting the components.

In addition, more and more light devices are integrated with connection capability. In wireless connection, antenna is a critical component. Grounding is essential and helpful in antenna design for electronic devices. Grounding plays a significant role in the proper functioning and performance of antennas.

The ringing effect in an LED light device refers to an undesired phenomenon where the LED's brightness exhibits rapid fluctuations, often appearing as flickering, pulsating, or visible rings or ripples around the light source. This effect can be particularly noticeable when the LED is dimmed or operated at low light levels. The ringing effect can create an uncomfortable lighting experience and may even lead to health concerns for some individuals, as flickering light can cause eye strain and headaches.

Please refer toFIG.1

The ringing effect is typically caused by various factors related to the LED driver circuit and the electrical characteristics of the LED itself. One of the main culprits is an improperly designed LED driver circuit that fails to provide stable and consistent current and voltage to the LED. When the driver circuit does not adequately filter the output, it can lead to rapid fluctuations in the LED's current, resulting in the ringing effect.

In addition to the driver circuit, inductive and capacitive effects within the LED driver circuit can contribute to the ringing issue. Inductive components like coils and transformers can cause sudden changes in current and magnetic fields, inducing unwanted oscillations. Similarly, capacitors can charge and discharge rapidly, creating fluctuations in the LED's current and voltage, contributing to the ringing effect.

Furthermore, if the LED driver circuit uses switching components such as transistors, their switching actions can generate transients or spikes in the circuit, leading to the ringing effect. Electromagnetic interference (EMI) or radio frequency interference (RFI) from other electronic components in the vicinity can also impact the LED driver circuit and cause fluctuations in the LED's illumination.

To mitigate the ringing effect in LED light devices, careful design considerations are essential. Employing high-quality LED driver circuits with proper filtering and component selection is crucial. Proper grounding techniques and attention to the electrical system's characteristics can help reduce EMI/RFI interference and stabilize the LED's performance. Compliance with relevant electrical and lighting standards is also important to ensure LED devices provide stable and flicker-free illumination, promoting a comfortable and safe lighting experience for users.

In some embodiments, the oscillation wave removal circuit includes multiple wave filters coupled in parallel.

FIG.8shows such an example. The oscillation wave removal circuit includes multiple wave filters coupled in parallel. In the example ofFIG.8, each wave filter has a RV (Varistor) part and an absorbing part30, which may include a RC (Resistor-Capacitor) module.

In some embodiments, at least two of the wave filters are assigned to filter different wave segments, so as to absorb undesired electrical waves in different ranges.

InFIG.5, at least one of the wave filter is composed of a resistor R1, a capacitor C2and a transient voltage suppressor RV.

A transient voltage suppressor (TVS) is a type of electronic device used to protect sensitive electronic circuits from transient voltage events, such as voltage spikes and surges. These transient events can occur due to lightning strikes, electrostatic discharge (ESD), power grid switching, or other sudden changes in the electrical environment. TVS devices are commonly used to safeguard electronic components, such as diodes, integrated circuits, and semiconductor devices, from damage caused by these voltage transients.

The main purpose of a TVS is to limit the voltage that is applied to the protected circuit during transient events. It does this by rapidly and effectively clamping the voltage to a safe level, diverting the excess current away from the sensitive components. When a transient voltage exceeds the predefined threshold, the TVS activates and creates a low-resistance path, allowing the excess current to flow through it and bypassing the protected circuit. Once the transient event subsides, the TVS returns to its high-impedance state, allowing the normal operation of the protected circuit to resume.

InFIG.8, at least one of the wave filter, e.g. the wave filter307, is composed of a resistor R1, a capacitor C3, a diode D1and a transient voltage suppressor RV.

In some embodiments, wherein the transient voltage suppressor comprises a p-n junction heavily doped to achieve a desired low breakdown voltage lower than 10 V so that the concentration of dopant atoms in the p and n regions is intentionally increased resulting in a thinner depletion region at the p-n junction.

In some embodiments, when a transient voltage spike occurs and the voltage across the transient voltage suppressor exceeds a breakdown voltage, the transient voltage suppressor enters the breakdown region, and its resistance drops significantly

In some embodiments, the transient voltage suppressor enters the breakeven region less than 1 ms. The parameter may be adjusted by calculating electronic formula for parameters of components to achieve the goal of less than 1 ms. Engineers in the filed know how to calculate the formula and choose proper components to achieve such task. With such feature, the wave filter works only for a short period of time, instead of being enabled all the time that may cause some derivation problem.

InFIG.13, the lighting apparatus may also include a ripping suppressor808for removing another type of ripping wave caused by the current source803.

The ripping suppressor808is coupled to an output of the current source803to remove a ripping wave in the driving currents supplied to the LED modules805.

In some embodiments, the controller80waits for a predetermined period every time when the driver module is initialized before adjusting a mixed color temperature of the LED modules.

In some embodiments, the controller804selectively enables the oscillation wave removal circuit805.

In some embodiments, abnormal statistics of the sudden abnormal voltage peak is recorded by the controller804for dynamically generating a removal schedule for enabling the oscillation wave removal circuit805by analyzing the recorded abnormal statistics.

For example, the abnormal cases are collected by recording when the abnormal cases appear and how to set the configuration to remove such oscillation waves to obtain an optimized effect. Such statistics data are collected by the controller804so as to dynamically control the operation of the oscillation wave removal circuit805.

InFIG.11, the driver module603is placed in a central area of the light source plate.

The multiple LED modules602are placed in peripheral areas of the light source plate.

In some embodiments, two power wires are coupled to the AC-DC converter for providing an AC power source.

FIG.6shows two power wires L and N coupled to a driver module for bringing external AC power to the lighting apparatus.

In some embodiments, a phase angle between the two power wires (L, N) are 90 degrees.

In some embodiments, a phase angle between the two power wires (L, N) are 270 degrees.

FIG.6also shows a PE (protective Earth) terminal. PE is an important safety feature in electrical systems and electronic devices. It refers to the intentional connection of conductive parts of electrical equipment and appliances to the Earth's conductive surface, typically through a grounding wire or conductor.

The primary purpose of Protective Earth is to ensure safety by providing a low-resistance path for fault currents to flow to the ground. In the event of a fault, such as a short circuit or insulation failure, current may flow through unintended conductive parts of the equipment, creating an electric shock hazard to users or causing damage to the device. By connecting these conductive parts to the Earth, any fault current is diverted safely away from users, reducing the risk of electrical shock.

In some embodiments, the substrate layer is connected to an earth protective terminal.

A phase angle between the earth protective terminal and one of the power wire is 90 degrees.

In some embodiments, the current source is a linear current regulator.

InFIG.12, there is a path708for conducting heat of the current source to the substrate layer703. Such path708may be made of metal material and may be variable forms, shapes and sizes for performing heat dissipation. The substrate layer703is a nice heat dissipation component for carrying out heat generated by the driver module.

FIG.1shows a lighting apparatus embodiment. InFIG.1, a transient voltage suppressor (TVS)10and a rectifier120are connected so that the TVS10removes certain undesired peak current and/or voltage not handled by the rectifier120.

FIG.2shows a different embodiment unlikeFIG.1. In addition to the rectifier120and the TVS10, there is an additional capacitor20incorporated to increase additional bank storage for removing undesired voltage and currents.

FIG.3shows a different embodiment ofFIG.2. InFIG.3, unlike using only a capacitor, in addition to the rectifier120and the TVS10, there is a R-C module that are used for absorbing the undesired voltage and current.

FIG.4shows a bridge circuit401which is coupled to an oscillation wave removal circuit402.

FIG.5shows using an RC module30in the oscillation wave removal circuit.

FIG.6shows using another RC module30in the oscillation wave removal circuit.

FIG.7shows another kind of oscillation wave removal circuit that includes a TVS and a RV.

FIG.8shows multiple wave filters are connected in parallel for removing undesired voltage and currents form the bridge circuit.

FIG.9shows a lighting apparatus embodiment.

InFIG.9, the lighting apparatus includes a filter module110, a rectifier module120for converting AC to DC, a power control module130as a current source for generating driving currents, a ripping filter140for removing ripping noise, a current absorbing module200for removing undesired voltage or current mentioned above, a color temperature control module150for sending control signals to the power control module130to generate different driving currents to the LED modules160based on different color temperature settings.

FIG.10shows a detailed circuit example to implement the filter module110, the rectifier module120for converting AC to DC, the power control module130as a current source for generating driving currents, the ripping filter140for removing ripping noise, the current absorbing module200, the color temperature control module150, the controller170and the LED modules160.

The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings.

The embodiments were chosen and described in order to best explain the principles of the techniques and their practical applications. Others skilled in the art are thereby enabled to best utilize the techniques and various embodiments with various modifications as are suited to the particular use contemplated.

Although the disclosure and examples have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the disclosure and examples as defined by the claims.