# US 7,408,270 B2 · Forward converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,408,270 B2 - Document ID: US7408270B2 - Status: Granted - Kind: B2 - Application number: 10/577,980 - Filed: 2004-10-28 - Published: 2007-03-29 - Granted: 2008-08-05 - Earliest claimed: 2003-11-04 - Assignees: NXP B.V. - Inventors: Thomas Dürbaum; Georg Sauerländer; Cornelis Johannes Adrianus Schetters - Web page: https://patentgrep.com/patent/US7408270B2 ## CPC - H02J 9/005: {using a power saving mode (for copiers G03G15/5004)} - H02M 3/33561: {having more than one ouput with independent control} - H02M 1/0032: {Control circuits allowing low power mode operation, e.g. in standby mode} - H02M 1/009: {having two or more independently controlled outputs (for DC-DC converter with intermediate AC H02M3/33561)} - 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 - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract Usually, power supplies are not capable of switching off part of the outputs of a main power supply during stand-by. Due to this, stand-by power supplies are used in addition to operation power supplies. Consistent with an example embodiment, a forward converter is provided, including switches in the rectifier circuit thereof. Due to this, the rectifier circuits may be selectively switched on and off. Advantageously, this may allow that the main outputs of such a forward converter are switched off while on stand-by. ## Claims ### Claim 1 A forward converter adapted for connection to a device, the forward converter comprising: a first rectifier circuit having a first output; a second rectifier circuit having a second output; wherein a first switch is provided in the first rectifier circuit; and wherein a second switch is provided in the second rectifier circuit; wherein, by switching the first and second switches, the first and second outputs may be selectively switched off, wherein, when the first switch is closed and the second switch is open, the first rectifier provides an operation voltage for the device; and wherein, when the first switch is open and the second switch is closed, the second rectifier provides a stand-by voltage for the device. ### Claim 2 (depends on 1) The forward converter of claim 1, wherein a third rectifier circuit is provided; wherein the third rectifier circuit is connected to the first rectifier circuit by a coupled inductor. ### Claim 3 (depends on 1) The forward converter of claim 1, wherein the first and second rectifier circuits each have a winding; wherein the windings of the first and second rectifier circuits are associated with the same transformer. ### Claim 4 (depends on 1) The forward converter of claim 1, wherein the forward converter is part of a PC power supply and the device is a PC. ### Claim 5 (depends on 1) The forward converter of claim 1, wherein a fourth rectifier circuit is provided; wherein a third switch is provided in a connection between the fourth rectifier circuit and the second rectifier circuit; wherein the third switch is closed during operation when the first rectifier circuit provides the operation voltage and wherein the third switch is open during operation when the second rectifier circuit provides the stand-by voltage. ### Claim 6 (depends on 1) The forward converter of claim 1, wherein the first switch is a bi-directional switch. ### Claim 7 Method of operating a forward converter adapted for connection to a device, the forward converter having a first rectifier circuit having a first output and a second rectifier circuit having a second output, wherein a first switch is provided in the first rectifier circuit, and wherein a second switch is provided in the second rectifier circuit, the method comprising the step of selectively switching off the first and second outputs by switching the first and second switches such that when the first switch is closed and the second switch is open, the first rectifier provides an operation voltage for the device, and when the first switch is open and the second switch is closed, the second rectifier provides a stand-by voltage for the device. ### Claim 8 (depends on 7) The method of claim 7, wherein a third rectifier circuit is provided, the method further comprising the step of: operating the third rectifier circuit and the first rectifier circuit by a coupled inductor. ### Claim 9 (depends on 7) The method of claim 7, wherein a fourth rectifier circuit is provided, wherein a third switch is provided in a connection between the fourth rectifier circuit and the second rectifier circuit, the method further comprising the step of: operating the third switch such that it is closed during operation when the first rectifier circuit provides the operation voltage and open during operation when the second rectifier circuit provides the stand-by voltage. ### Claim 10 (depends on 1) The forward converter of claim 1, further comprising a fourth rectifier circuit connected to the third rectifier circuit by a coupled inductor. ### Claim 11 (depends on 1) The forward converter of claim 1, wherein the first switch is a high frequency switch. ### Claim 12 (depends on 1) The forward converter of claim 1, wherein the first switch is regulated by a duty cycle of a power source switch. ### Claim 13 (depends on 12) The forward converter of claim 12, wherein the second switch is adapted as a static switch. ### Claim 14 (depends on 1) The forward converter of claim 1, wherein the first switch and the second switch are static switches. ### Claim 15 (depends on 1) The forward converter of claim 1, wherein the first switch and the second switch are not adapted to switch with cycles of a duty cycle.