# US 8,786,204 B2 · DC/DC converter and driving apparatus having the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,204 B2 - Document ID: US8786204B2 - Status: Granted - Kind: B2 - Application number: 13/420,229 - Filed: 2012-03-14 - Published: 2013-07-04 - Granted: 2014-07-22 - Earliest claimed: 2011-12-28 - Assignees: Samsung Electro-Mechanics Co., Ltd. - Applicants: Sang Gab Park; Nam Jin Park; Heung Gyoon Choi; Han Hee Lee; Hyo Joong An; Kyu Min Park; Su Hun Jo - Inventors: Sang Gab Park; Nam Jin Park; Heung Gyoon Choi; Han Hee Lee; Hyo Joong An; Kyu Min Park; Su Hun Jo - Web page: https://patentgrep.com/patent/US8786204B2 ## CPC - H02M 3/33592: {having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer} - H05B 45/60: Circuit arrangements for operating LEDs comprising organic material, e.g. for operating organic light-emitting diodes [OLED] or polymer light-emitting diodes [PLED] - Y02B 20/30: Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - 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 There are provided a DC/DC converter and a driving apparatus having the same. The DC/DC converter includes a DC/DC converter part converting an input power into a predetermined DC power by switching the input power to thereby supply the converted DC power to a light emitting device; and a control part controlling switching of the DC/DC converter part in accordance with a driving signal applied to the light emitting device to thereby control a voltage level of the DC power. ## Claims ### Claim 1 A DC/DC converter, comprising: a DC/DC converter part converting an input power into a predetermined DC power by switching the input power to thereby supply the converted DC power to a light emitting device; and a control part controlling switching of the DC/DC converter part in accordance with driving power supplied to the light emitting device and a driving signal controlling brightness of the light emitting device to thereby control a voltage level of the DC power, wherein the control part includes: a comparison part comparing a predetermined reference signal with the DC power of the DC/DC converter part and a signal level of the driving signal, and a switching control part controlling switching of the DC/DC converter part in accordance with a comparison result of the comparison part. ### Claim 2 (depends on 1) The DC/DC converter of claim 1, wherein the DC/DC converter part includes: a switching part switching the input power in accordance with a switching control of the control part; a transformer having a primary winding receiving the switched power from the switching part, and a secondary winding having a predetermined winding ratio with regard to the primary winding and outputting a power transformed in accordance with the winding ratio; and a rectification part having a synchronous rectification element rectifying the transformed power from the secondary winding of the transformer. ### Claim 3 (depends on 2) The DC/DC converter of claim 2, wherein the control part is synchronized with a switching control of the switching part to thereby control ON/OFF switching of the synchronous rectification element of the rectification part. ### Claim 4 (depends on 3) The DC/DC converter of claim 3, wherein the switching control part controls the switching of the switching part of the DC/DC converter part and the switching of the synchronous rectification element of the DC/DC converter part in accordance with the comparison result of the comparison part. ### Claim 5 (depends on 3) The DC/DC converter of claim 3, wherein the control part controls switching-on duty of the switching part in accordance with on-time duty of the driving signal. ### Claim 6 (depends on 2) The DC/DC converter of claim 2, wherein the switching part has a phase shift full bridge (PSFB) switch structure or a half bridge switch structure. ### Claim 7 A driving apparatus, comprising: a power factor correction part switching a rectified power to correct a power factor; a DC/DC converter part switching the power in which the power factor is corrected from the power factor correction part, and converting the switched power into a predetermined DC power to thereby supply the converted DC power to an organic light emitting diode (OLED); and a control part controlling switching of the DC/DC converter part in accordance with driving power supplied to the OLED and a driving signal controlling brightness of the OLED to thereby control a voltage level of the DC power, wherein the control part includes: a comparison part comparing a predetermined reference signal with the DC power of the DC/DC converter part and a signal level of the driving signal, and a switching control part controlling switching of the DC/DC converter part in accordance with a comparison result of the comparison part. ### Claim 8 (depends on 7) The driving apparatus of claim 7, wherein the DC/DC converter part includes: a switching part switching the power in which the power factor is corrected in accordance with a switching control of the control part, a transformer having a primary winding receiving the switched power from the switching part, and a secondary winding having a predetermined winding ratio with regard to the primary winding to thereby output a power transformed in accordance with the winding ratio, and a rectification part having a synchronous rectification element rectifying the transformed power from the secondary winding of the transformer. ### Claim 9 (depends on 8) The driving apparatus of claim 8, wherein the control part is synchronized with a switching control of the switching part to thereby control ON/OFF switching of the synchronous rectification element of the rectification part. ### Claim 10 (depends on 9) The driving apparatus of claim 9, wherein the switching control part controls the switching of the switching part of the DC/DC converter part and the switching of the synchronous rectification element of the DC/DC converter part in accordance with the comparison result of the comparison part. ### Claim 11 (depends on 9) The driving apparatus of claim 9, wherein the control part controls switching-on duty of the switching part in accordance with on-time duty of the driving signal. ### Claim 12 (depends on 8) The driving apparatus of claim 8, wherein the switching part has a phase shift full bridge (PSFB) switch structure or a half bridge switch structure.