# US 11,121,579 B2 · Circuit for power supply and electronic device using same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,121,579 B2 - Document ID: US11121579B2 - Status: Granted - Kind: B2 - Application number: 16/405,336 - Filed: 2019-05-07 - Published: 2020-09-10 - Granted: 2021-09-14 - Earliest claimed: 2019-03-05 - Assignees: Fu Tai Hua Industry (Shenzhen) Co., Ltd.; Hon Hai Precision Industry Co., Ltd. - Applicants: Fu Tai Hua Industry (Shenzhen) Co., Ltd.; Hon Hai Precision Industry Co., Ltd. - Inventors: Yong-Xing Yang - Web page: https://patentgrep.com/patent/US11121579B2 ## CPC - H02J 9/061: {for DC powered loads} - H05B 47/10: Controlling the light source - H02J 7/35: with light sensitive cells - H05B 47/105: in response to determined parameters - Y02B 10/70: Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A power supply circuit supplying power to components of a fixed or mobile electrical or electronic device includes a main battery, an auxiliary battery, and main and auxiliary switch units. The main battery and the main switch unit form a main power supply circuit, and the auxiliary battery and the auxiliary switch unit form an auxiliary power supply circuit. The main switch unit includes a lighting unit controlling the switching on or off of the auxiliary switch unit. When the lighting unit is switched on, the auxiliary switch unit is switched off and the auxiliary power supply circuit is disabled. When the lighting unit is switched off, the auxiliary switch unit is switched on and the auxiliary power supply circuit is enabled. An electronic device including such a power supply circuit is also provided. ## Claims ### Claim 1 A power supply circuit supplying power to an electronic device, comprises a main battery, an auxiliary battery, a main switch unit and an auxiliary switch unit, the main battery and the main switch unit form a main power supply circuit to power the electronic device, the auxiliary battery and the auxiliary switch unit form an auxiliary power supply circuit to power the electronic device, the main switch unit comprises a lighting unit, wherein when the main switch is switched on, a current from the main battery to the electronic device is applied to the lighting unit, and the lighting unit is illuminated, the auxiliary switch unit is switched off if the light unit is emitting light and the auxiliary power supply circuit is disabled from powering the electronic device, when the lighting unit is not emitting light, the auxiliary switch unit is switched on and the auxiliary power supply circuit is enabled to power the electronic device. ### Claim 2 (depends on 1) The power supply circuit as claimed in claim 1, wherein the main switch unit comprises a current monitoring unit and an electronic switch, the electronic switch is connected with the lighting unit in series to form a branch, the current monitoring unit monitors a value of current flowing through the main switch unit; the processing unit controls the electronic switch on or off according to the value of the current, the switching on of the electronic switch switches on the lighting unit to illuminate, and the switching off of the electronic switch switches off the lighting unit. ### Claim 3 (depends on 2) The power supply circuit as claimed in claim 2, wherein when the current value falls below a first threshold value, the processing unit controls the electronic switch to be switched off, the lighting unit is switched off and the auxiliary switch unit is switched on, thereby the auxiliary power supply circuit is enabled to power the electronic device. ### Claim 4 (depends on 3) The power supply circuit as claimed in claim 3, wherein when the current value goes beyond a second threshold value, the processing unit controls the electronic switch to be switched on, the lighting unit is illuminated according to the current from the main battery to the electronic device, and the auxiliary switch unit is switched off if the light unit is emitting light, thereby the auxiliary power supply circuit is disabled from powering the electronic device, the second threshold value is greater than or equal to the first threshold value. ### Claim 5 (depends on 4) The power supply circuit as claimed in claim 4, wherein electronic switch is controlled by a processing unit of the electronic device which compares the current value with the first threshold value and the second threshold value. ### Claim 6 (depends on 2) The power supply circuit as claimed in claim 2, wherein the main switch unit comprises a diode, the diode is connected in parallel to the branch, the main battery supply electronic power to the electronic device via the diode, a current path for backflow currents are defined from the diode to the main battery. ### Claim 7 (depends on 1) The power supply circuit as claimed in claim 1, wherein the auxiliary switch unit comprises a light switch controlled by light from the lighting unit, the light switch switches off when the lighting unit is illuminated based on the current from the main battery to the electronic device, and the light switch switches on when the lighting unit is not emitting light, thereby the auxiliary switch unit switches off or on accordingly. ### Claim 8 (depends on 1) The power supply circuit as claimed in claim 1, wherein the auxiliary battery is a solar panel which converts light energy into electrical power being stored into the auxiliary battery. ### Claim 9 (depends on 1) The power supply circuit as claimed in claim 1, wherein the main power supply circuit comprises a voltage stabilizing unit for stabilizing a voltage level of the main power supply circuit. ### Claim 10 (depends on 1) The power supply circuit as claimed in claim 1, wherein the auxiliary power supply circuit comprises a voltage stabilizing unit for stabilizing a voltage level of the auxiliary power supply circuit. ### Claim 11 An electronic device comprising electronic device and a power supply circuit supplying power to the electronic device, the power supply circuit comprises a main battery, an auxiliary battery, a main switch unit and an auxiliary switch unit, the main battery and the main switch unit form a main power supply circuit to power the electronic device, the auxiliary battery and the auxiliary switch unit form an auxiliary power supply circuit to power the electronic device, the main switch unit comprises a lighting unit, wherein when the main switch is switched on, a current from the main battery to the electronic device is applied to the lighting unit, and the lighting unit is illuminated, the auxiliary switch unit is switched off if the light unit is emitting light and the auxiliary power supply circuit is disabled from powering the electronic device, when the lighting unit is not emitting light, the auxiliary switch unit is switched on and the auxiliary power supply circuit is enabled to power the electronic device. ### Claim 12 (depends on 11) The electronic device as claimed in claim 11, wherein the main switch unit comprises a current monitoring unit and an electronic switch, the electronic switch is connected with the lighting unit in series to form a branch, the current monitoring unit monitors a value of current flowing through the main switch unit; the processing unit controls the electronic switch on or off according to the value of the current, the switching on of the electronic switch turns on the lighting unit to illuminate, and the switching off of the electronic switch turns off the lighting unit. ### Claim 13 (depends on 12) The electronic device as claimed in claim 12, wherein the electronic device comprises a processing unit, the processing unit receives the value of current from the current monitoring unit and compares the value of current with a first threshold value and a second threshold value greater than or equal to the first threshold value, the processing unit switches off the electronic switch when the value of current falls below the first threshold value and switches on the electronic switch when the value of current goes beyond the second threshold value. ### Claim 14 (depends on 11) The electronic device as claimed in claim 11, wherein the main switch unit comprises a diode, the diode is connected in parallel to the branch, the diode allows the main battery supply electronic power to the electronic device via the diode, a current path for backflow currents are defined from the diode to the main battery. ### Claim 15 (depends on 11) The electronic device as claimed in claim 11, wherein the auxiliary switch unit comprises a light switch controlled by light from the lighting unit, the light switch switches off when the lighting unit is illuminated according to the current from the main battery to the electronic device, and switches on when the lighting unit is if the light unit is not emitting light, thereby the auxiliary switch unit switches off or on accordingly. ### Claim 16 (depends on 11) The electronic device as claimed in claim 11, wherein the auxiliary battery is detachably amounted in the electronic device. ### Claim 17 (depends on 11) The electronic device as claimed in claim 11, wherein the auxiliary battery is a solar panel which converts light energy into electrical power being stored into the auxiliary battery. ### Claim 18 (depends on 11) The electronic device as claimed in claim 11, wherein all functions of the electronic device is enabled when the auxiliary power supply circuit is disabled from powering the electronic device, and partly of the functions of the electronic device is enabled when the auxiliary power supply circuit is enabled to power the electronic device.