# US 11,307,525 B2 · Printed circuit board mounting piezoelectric transformer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,307,525 B2 - Document ID: US11307525B2 - Status: Granted - Kind: B2 - Application number: 16/859,139 - Filed: 2020-04-27 - Published: 2020-08-13 - Granted: 2022-04-19 - Earliest claimed: 2017-02-13 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Taro Minobe; Norikazu Sugiyama; Ryo Matsumura - Web page: https://patentgrep.com/patent/US11307525B2 ## CPC - G03G 15/80: {Details relating to power supplies, circuits boards, electrical connections} - H02M 3/33507: {with automatic control of the output voltage or current, e.g. flyback converters (H02M3/33561, H02M3/33569 take precedence)} - H05K 3/303: with surface mounted components (H05K3/32 takes precedence) - H05K 3/3415: {on both sides of the substrate or combined with lead-in-hole components} - H10N 30/40: with electrical input and electrical output, e.g. functioning as transformers - H10N 30/804: {for piezoelectric transformers} - H10N 30/88: Mounts; Supports; Enclosures; Casings - H05K 1/181: associated with surface mounted components - H05K 3/3494: Heating processes for reflow soldering - H05K 2201/10083: Electromechanical or electro-acoustic component, e.g. microphone - H05K 2201/10545: Related components mounted on both sides of the PCB - H05K 2203/1572: Processing both sides of a PCB by the same process; Providing a similar arrangement of components on both sides; Making interlayer connections from two sides - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - 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) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A printed circuit board comprises a first mounting surface, a second mounting surface, and a piezoelectric transformer. The piezoelectric transformer has a piezoelectric substance, external electrodes, and a frame substrate. The second mounting surface has a projection region. There is a first region from a first location, where an end portion further from the output electrode out of end portions of the input electrode is projected onto the second mounting surface in the projection region, to a second location, where an end portion closer to the output electrode out of the end portions of the input electrode is projected onto the second mounting surface, the first region being a mounting allowed region where an electronic component is mounted. ## Claims ### Claim 1 A method of mounting an electronic component, the method comprising: applying solder to a first mounting surface of a printed circuit board; surface-mounting a piezoelectric transformer to the first mounting surface and mounting to the first mounting surface a resistor connected in parallel to a pair of input electrodes of the piezoelectric transformer; soldering the piezoelectric transformer and the resistor to the first mounting surface by inserting the printed circuit board into a reflow oven; applying solder to a second mounting surface of the printed circuit board; mounting a semiconductor component for forming a driving circuit for driving the piezoelectric transformer to the second mounting surface; and soldering the semiconductor component to the second mounting surface by inserting the printed circuit board into the reflow oven. ### Claim 2 (depends on 1) The method according to claim 1, wherein the resistor is a first resistor, wherein the mounting of the semiconductor component for forming the driving circuit for driving the piezoelectric transformer on the second mounting surface includes mounting to the second mounting surface a second resistor connected in parallel to the pair of input electrodes of the piezoelectric transformer, and wherein the soldering of the semiconductor component to the second mounting surface by inserting the printed circuit board into the reflow oven includes soldering the second resistor to the second mounting surface by inserting the printed circuit board into the reflow oven. ### Claim 3 (depends on 1) The method according to claim 1, wherein a resistance of the resistor reduces a pyroelectric voltage generated in the pair of input electrodes of the piezoelectric transformer by a piezoelectric effect when the printed circuit board passes through the reflow oven in order to solder the semiconductor component to the second mounting surface, and the resistance of the resistor has a value so that a decrease in power supply performance of a power supply circuit that includes the piezoelectric transformer is within a predetermined range, and wherein the resistance of the first resistor is greater than or equal to 6.0 kΩ and less than or equal to 3.0 MΩ. ### Claim 4 (depends on 2) The method according to claim 2, wherein a resistance of the second resistor reduces a pyroelectric voltage generated in the pair of input electrodes of the piezoelectric transformer by a piezoelectric effect when the printed circuit board passes through the reflow oven in order to solder the semiconductor component to the second mounting surface, and the resistance of the second resistor has a value so that a decrease in power supply performance of a power supply circuit that includes the piezoelectric transformer is within a predetermined range, and wherein the resistance of the second resistor is greater than or equal to 6.0 kΩ and less than or equal to 3.0 MΩ. ### Claim 5 A printed circuit board comprising: a first mounting surface; a second mounting surface; a first electronic component soldered to the first mounting surface; and a second electronic component soldered to the second mounting surface, wherein the first electronic component includes: a piezoelectric transformer surface-mounted to the first mounting surface, and a resistor mounted to the first mounting surface and connected in parallel to a pair of input electrodes of the piezoelectric transformer, and wherein the second electronic component includes: a semiconductor component mounted to the second mounting surface and configured to form a driving circuit for driving the piezoelectric transformer. ### Claim 6 (depends on 5) The printed circuit board according to claim 5, wherein the electrode is a first electrode, and wherein the printed circuit board further comprises a second resistor mounted to the second mounting surface and connected in parallel to the pair of input electrodes of the piezoelectric transformer. ### Claim 7 (depends on 5) The printed circuit board according to claim 5, wherein a resistance of the resistor reduces a pyroelectric voltage generated in the pair of input electrodes of the piezoelectric transformer by a piezoelectric effect when the printed circuit board passes through the reflow oven in order to solder the semiconductor component to the second mounting surface, and the resistance of the resistor has a value so that a decrease in power supply performance of a power supply circuit that includes the piezoelectric transformer is within a predetermined range, and wherein the resistance of the first resistor is greater than or equal to 6.0 kΩ and less than or equal to 3.0 MΩ. ### Claim 8 (depends on 6) The printed circuit board according to claim 6, wherein a resistance of the second resistor reduces a pyroelectric voltage generated in the pair of input electrodes of the piezoelectric transformer by a piezoelectric effect when the printed circuit board passes through the reflow oven in order to solder the semiconductor component to the second mounting surface, and the resistance of the second resistor has a value so that a decrease in power supply performance of a power supply circuit that includes the piezoelectric transformer is within a predetermined range, and wherein the resistance of the second resistor is greater than or equal to 6.0 kΩ and less than or equal to 3.0 MΩ. ### Claim 9 (depends on 5) A power supply apparatus comprising: the printed circuit board according to claim 5; a piezoelectric transformer surface-mounted to the first mounting surface, and a driving circuit configured to drive the piezoelectric transformer. ### Claim 10 (depends on 9) An image forming apparatus comprising: an image carrier; a charging unit configured to uniformly charge the image carrier; an exposure unit configured to form an electrostatic latent image by exposing the image carrier; a developing unit configured to form a toner image by developing the electrostatic latent image; a transfer unit configured to transfer the toner image to a sheet; and the power supply apparatus according to claim 9, which is configured to generate a charging voltage supplied to the charging unit, a developing voltage supplied to the developing unit, or a transfer voltage supplied to the transfer unit. ### Claim 11 A method for mounting an electric component, the method comprising: applying solder to a second mounting surface of a printed circuit board; mounting a semiconductor component and a resistor on the second mounting surface, the semiconductor component forming a driving circuit for driving a piezoelectric transformer, and the resistor connected in parallel to an input electrode pair of the piezoelectric transformer; soldering the semiconductor component and the resistor on the second mounting surface by inserting the printed circuit board into a reflow oven; applying solder to a first mounting surface of the printed circuit board; surface-mounting the piezoelectric transformer on the first mounting surface; and soldering the piezoelectric transformer on the first mounting surface by inserting the printed circuit board into a reflow oven. ### Claim 12 A printed circuit board comprising: a first mounting surface; a second mounting surface; a first electronic component soldered to the first mounting surface; and a second electronic component soldered to the second mounting surface, wherein the first electronic component includes: a piezoelectric transformer surface-mounted to the first mounting surface, and wherein the second electronic component includes: a semiconductor component mounted to the second mounting surface and configured to form a driving circuit for driving the piezoelectric transformer, and a resistor mounted to the second mounting surface and connected in parallel to a pair of input electrodes of the piezoelectric transformer. ### Claim 13 (depends on 12) A power supply apparatus comprising: the printed circuit board according to claim 12; a piezoelectric transformer surface-mounted to the first mounting surface, and a driving circuit configured to drive the piezoelectric transformer. ### Claim 14 (depends on 13) An image forming apparatus comprising: an image carrier; a charging unit configured to uniformly charge the image carrier; an exposure unit configured to form an electrostatic latent image by exposing the image carrier; a developing unit configured to form a toner image by developing the electrostatic latent image; a transfer unit configured to transfer the toner image to a sheet; and the power supply apparatus according to claim 13, which is configured to generate a charging voltage supplied to the charging unit, a developing voltage supplied to the developing unit, or a transfer voltage supplied to the transfer unit.