US Pat. No. 10,117,296

LED STRAIGHT TUBE LAMPS

CH LIGHTING TECHNOLOGY CO...

1. A LED straight tube lamp comprising a tube, lamp caps with contact pins and located on both ends of the tube, a first rectifying unit and a second rectifying unit and a filter unit that are coupled with the pins on the two ends respectively, and a switch unit that is located between the rectifying units and the filter unit characterized in that the switch unit comprises:a sampling end that is coupled with either one or both of the contact pins,
a first end that is earthed, and
a second end that is coupled with the filter unit;
wherein the switch unit further comprises a rectifying module a reference module, an impedance detecting module, a control module, a driver module and a transistor;
a source electrode and a drain electrode of the transistor are connected with the first end and second end of the switch unit, respectively;
the sampling end outputs sampling signal to the rectifying module, which outputs rectified sampling signal to the reference module;
the impedance detecting module is used to detect the current on the switch unit's first end; the control module is used to compare the current detected by the impedance detecting module and the current outputted by the reference module and output control signal to the driver module; the driver module outputs high-low level signal to the grid of the transistor; and
wherein when the contact pin on either end of the LED straight tube lamp is connected to a power supply, if the current detected by the impedance detecting module is lower than a set value, the switch unit will be disconnected; if current detected by the impedance detecting module equal to or higher than the set value, the switch unit will be connected.

US Pat. No. 10,034,338

FULL VOLTAGE SEGMENTED LINEAR CONSTANT-CURRENT LED DRIVE CIRCUIT IN AUTO SWITCHOVER MODE

CH LIGHTING TECHNOLOGY CO...

1. A full voltage segmented linear constant-current LED drive circuit in an auto switchover mode, comprising a minimum of two groups of LEDs in series connection and a voltage detection and control circuit, characterized in that:positive terminals of each group of LEDs are connected to a power source via a change-over switch; negative terminals of each group of LEDs are grounded via corresponding control switches;
wherein, one of the minimum of two groups comprises a minimum of two LED units in series connection; a negative terminal of each LED unit is grounded;
the change-over switch is connected to and controlled by the voltage detection and control circuit; the voltage detection and control circuit detects a power voltage from an output terminal of the power source and control the change-over switch accordingly to change inter-group connection mode and ON/OFF of respective LED units;
wherein each group of LEDs comprises at least one or more LEDs in series connection; in the group comprising the minimum of two LED units, each LED unit comprises at least one or more LEDs in series connection;
wherein each control switch of the minimum of two groups of LEDs is grounded via a sampling resistor, and is provided with a comparator; a sampling terminal of the comparator is connected to the sampling resistor, which aims to input constant-current protection signals to the corresponding control switch after comparison with benchmark signals;
wherein the change-over switch comprises a triode and a metal oxide semiconductor field effect transistor (MOS); wherein, a collector and an emitter of the triode are respectively connected to the positive terminal of the one of the minimum of two groups of LEDs and the positive terminal of the power source; the base of the triode is connected to the power source via a first voltage division resistor; and
a drain of the metal oxide semiconductor field effect transistor (MOS) is connected to the base of the triode via a second voltage division resistor, and a source of the MOS is grounded; a gate of the MOS is connected to the voltage detection and control circuit wherein the voltage detection and control circuit aims to collect the power voltage from the output terminal of the power source and currents from the sampling resistors and output a control signal to the gate of the MOS.

US Pat. No. 10,342,077

LED DRIVING CIRCUIT AND TUBE LAMP

CH LIGHTING TECHNOLOGY CO...

1. An LED driving circuit, comprising:a rectifying unit comprising an input terminal, an output terminal and a grounding terminal, wherein the grounding terminal of the rectifying unit is electrically connected to a first ground wire;
a first filtering unit comprising a first input terminal, a second input terminal and an output terminal, wherein the first input terminal of the first filtering unit is electrically connected to the output terminal of the rectifying unit;
a voltage converting unit comprising an input terminal and an output terminal, wherein the input terminal of the voltage converting unit is electrically connected to the output terminal of the first filtering unit, wherein the voltage converting unit is configured to convert a direct current voltage inputted to the input terminal of the voltage converting unit into another or multiple direct current voltages, and converted voltages are outputted from the output terminal of the voltage converting unit; and
an impedance detection and protection unit comprising an input terminal and a grounding terminal, wherein the input terminal of the impedance detection and protection unit is electrically connected to the second input terminal of the first filtering unit, the grounding terminal of the impedance detection and protection unit is electrically connected to the first ground wire, and the impedance detection and protection unit is configured to detect an impedance between the second input terminal of the first filtering unit and the first ground wire, so as to control the second input terminal of the first filtering unit to connect to or disconnect from the first ground wire according to a magnitude of the detected impedance.

US Pat. No. 10,716,184

LED TUBE

CH LIGHTING TECHNOLOGY CO...

1. An LED lamp comprising a driving circuit controlled by a switch during use, wherein the driving circuit comprises:a dimming controller having a switch state monitoring port and a power supply port, wherein the power supply voltage gradually decreases after the switch is turned off, and when the switch is turned on again, if the power supply voltage is between a first set value and a second set value, the dimming controller outputs a driving signal with the same value as the driving signal when the switch is off, so that the current flowing through the LED light source remains unchanged; when the supply voltage is lower than the second set value, the dimming controller outputs a dynamically changing driving signal to cause current flowing through the LED light source gradually changing from a first extreme value to a second extreme value; and
a power conversion unit, configured to receive the driving signal and provide energy for the LED light source;wherein the dimming controller comprises:a dimming trigger module outputting a corresponding trigger signal according to the switch state;
an undervoltage detection module for detecting a supply voltage of the input dimming controller;
a reference signal generator outputting a reference signal having a fixed potential or a gradient change according to magnitude of the power supply voltage at a time when the switch is on;
a PWM pulse width modulation module that is configured to receive the reference signal and synthesize the PWM pulse signal.

US Pat. No. 10,612,730

U-SHAPED LED TUBE

CH LIGHTING TECHNOLOGY CO...

1. A U-shape LED tube, comprising a U-shape tube body and light bars fixed inside the U-shape tube body, the U-shape tube body comprises two straight tube sections and one curved section, and the curved section comprises two semicircle tubes, which is characterized in that: the two ends of the curved section are provided with shrinkage parts that are inserted in the straight tube sections, and the shrinkage parts are in fixed connection with the straight tube sections through ultrasonic welding;wherein the light bar comes in integrated construction, and an inward depression or concave on the edge of the light bar is provided at the connecting point between the shrinkage part and the straight tube section;
wherein each of the two straight tube sections are in integrated construction; and
wherein an outer diameter of the shrinkage part is less than that of the straight tube section, and an inner diameter of the shrinkage part is the same as that of the straight tube section.