# Relieved Red Power Laces ## Description Piggyback USB2.0 Type-A Mezzanine Interposer with Reverse-Current Protection, Tamper-Resistant D+/D− One-Shot Shunt, Supercap Backup, and SI-Compliant Chassis-Mounted Shielding ## Project Details - **Owner:** sapphirelinux - **Created:** 11/29/2025 - **Last Updated:** 11/29/2025 - **Visibility:** Public - **Role:** Power Conversion - **J2 outline width:** 30px - **Net Type:** Power - **J2 outline height:** 7.62mm - **J2 target footprint family:** ONSHORE_USB-A1VSB6 - **Bus Type:** USB 2.0 - **Connector Pitch:** 2.5mm - **Connector Positions:** 4 + shield stakes - **Connectivity:** USB - **Domain:** Telecommunications - **Part Type:** Mechanical - **Power Requirements:** USB - **Chassis mounting hole positions:** [(-6.57mm, 0mm), (6.57mm, 0mm)] - **J2 target connector family:** On Shore USB-A1VSB6 - **J2 piggyback capture pad strategy:** Adjustable slotted pad pattern to accommodate typical 4-pin right-angle through-hole USB-A receptacles with ~2.5 mm pin pitch and shield stakes at ±6.57 mm - **Role Details:** USB 2.0 Type-A tamper-detect interposer with integrated reverse-current protection, polyfuse, VBUS TVS, supercapacitor-based energy store, and one-shot–latched D+/D- shunt for tamper response. Implemented on a standard 4-layer stackup with inner planes for VBUS and GND/return to support USB 2.x signal integrity in a compact interposer form factor. - **J2 outline depth:** 12mm - **System Architecture Diagram:** mermaid graph TD J2["J2: USB-A Right-Angle Receptacle"] Mezz["Mezzanine PCB (Piggyback Interposer)"] CHASSIS["Chassis / Rear I/O Shield"] %% Mechanical mating J2 -->|Pin Contacts| Mezz Mezz -->|Shield Stakes| CHASSIS subgraph Power Path MP5016["U1: MP5016 Load Switch"] FUSE["F1: Polyfuse"] TVS["VBUS TVS Diode"] J2_VBUS["J2 VBUS Pad"] GND[(GND Plane)] Mezz -->|VBUS_IN| MP5016 MP5016 -->|VBUS_PROT| FUSE FUSE -->|VBUS_OUT| TVS TVS -->|Clamp to GND| GND TVS -->|VBUS_OUT| J2_VBUS end subgraph Tamper Circuit U2["U2: LTC6993 One-Shot Timer"] U3["U3: LTC3625 Supercap Charger"] U4["U4: D+/D- Shunt Switch"] Dshort["D+/D- Short Node"] J2_VBUS -->|VBUS_SENSE| U2 U3 -->|*PFO (Power-Good)| U2 U2 -->|LATCH_ENABLE| U4 U4 -->|Short D+/D-| Dshort end subgraph SI & ESD Protection Rser["R1/R2: 22Ω Series Resistors"] ESD["U5: USBLC6 ESD Array"] TP2["D+ Test Pad"], TP3["D- Test Pad"] J2 -->|D+/D-| Rser Rser -->|D+_INT / D-_INT| ESD ESD -->|Protected D+/D-| J2 ESD -->|Clamp| GND Rser --> TP2 & TP3 end %% Shield bonding SHIELD["Connector Shield"] J2 -->|SHIELD| SHIELD SHIELD -->|Bond| CHASSIS ## Key Components ### D1 — [USBLC6-2SC6](https://www.flux.ai/collinsemasi/usblc6-2sc6~jt.md) - Voltage - Breakdown: 6V - Datasheet URL: https://www.st.com/content/ccc/resource/technical/document/datasheet/06/1d/48/9c/6c/20/4a/b2/CD00050750.pdf/files/CD00050750.pdf/jcr:content/translations/en.CD00050750.pdf - Manufacturer Part Number: USBLC6-2SC6 - Role Details: Transient voltage suppression for USB VBUS - Unidirectional Channels: 2 - Package: SOT-23 - Voltage - Reverse Standoff: 5.25V - Part Type: ESD PROTECTION - Operating Temperature: -40°C ~ 150°C (TJ) - Role: Protection - Manufacturer Name: STMicroelectronics **Pins:** - 1 [pin 1] - 3 [pin 3] - 4 [pin 4] - 6 [pin 6] - GND [pin 2] - VBUS [pin 5] ### D3 — [6V Unidirectional TVS Diode](https://www.flux.ai/corynrobinson/6v-unidirectional-tvs-diode~4n.md) - Role: Protection - Part Type: Diode - Breakdown Voltage: 6V - Manufacturer Part Number: SMAJ6.0A - Package or Case Code: D_SMA - Manufacturer Name: Littlefuse - Datasheet URL: https://www.littelfuse.com/~/media/electronics/datasheets/tvs_diodes/littelfuse_tvs_diode_smaj_datasheet.pdf.pdf - Role Details: Transient voltage suppression for USB VBUS **Pins:** - A - K ### F1 — [ASMD2018-100](https://www.flux.ai/lcsc/asmd2018-100~j5j8.md) - Manufacturer Part Number: ASMD2018-100 - Package: F2018 - Package or Case Code: F2018 - JLCPCB Part Class: Extended Part - LCSC Part Number: C135370 - Product Info Url: https://lcsc.com/product-detail/Surface-Mount-Fuses_1A-Self-recovery_C135370.html - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2305151204_Shenzhen-JDT-Fuse-ASMD2018-100_C135370.pdf - Role: Protection - Manufacturer Name: JDTfuse(集电通) - Part Type: Resettable Fuses - Current Rating: 1A - Role Details: Overcurrent protection for USB VBUS **Pins:** - 1 [pin 1] - 2 [pin 2] ### J1 — [USB-A Plug PCB](https://www.flux.ai/jharwinbarrozo/usb-a-plug-pcb~6lp.md) - Part Type: USB A - Role Details: Upstream USB Type-A plug for host connection - Role: Connector - Manufacturer Part Number: USB-A PCB Plug **Pins:** - D- [pin 2] - D+ [pin 3] - GND [pin 4] - VBUS [pin 1] ### J2 — [USB-A1VSB6](https://www.flux.ai/vasyl/usb-a1vsb6~qx.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: OST - Role: Connector - Datasheet URL: https://www.snapeda.com/parts/USB-A1VSB6/On%20Shore/datasheet/ - Part Type: USB A - Manufacturer Part Number: USB-A1VSB6 - Role Details: Downstream USB Type-A receptacle for YubiKey **Pins:** - D- [pin 2] - D+ [pin 3] - GND [pin 4] - SHIELD [pin S1] - SHIELD__1 [pin S2] - VUSB [pin 1] ### J3 — [USB type A](https://www.flux.ai/vasyl/usb-type-a~j7.md) - Part Type: USB Connectors - Datasheet URL: https://www.snapeda.com/parts/61400416021/Wurth%20Electronics/datasheet/ - Role Details: Right-angle USB Type-A receptacle, 4-pin through-hole, for piggyback mounting - Manufacturer Name: CNC Tech - Manufacturer Part Number: USB type A - Role: Connector **Pins:** - D- [pin 2] - D+ [pin 3] - GND [pin 4] - VBUS [pin 1] ### SHLD1 — [MS110-10S-NS](https://www.flux.ai/vasy_skral/ms110-10s-ns~amh.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://api.masach.com/media/catalog/product/file/MS110-10.pdf - Role Details: USB shield bonding stake for chassis ground - Manufacturer Name: Masach Tech Ltd. - Part Type: RF Shield - Manufacturer Part Number: MS110-10S-NS - Role: Mechanical **Pins:** - Shield [pin 1] ### SHLD2 — [MS110-10S-NS](https://www.flux.ai/vasy_skral/ms110-10s-ns~amh.md) - Part Type: RF Shield - Manufacturer Name: Masach Tech Ltd. - Role Details: USB shield bonding stake for chassis ground - Manufacturer Part Number: MS110-10S-NS - Role: Mechanical - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://api.masach.com/media/catalog/product/file/MS110-10.pdf **Pins:** - Shield [pin 1] ### TP1 — [5019](https://www.flux.ai/adrian95/5019~fxh.md) - Manufacturer Name: Keystone Electronics - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: 5019 - Datasheet URL: https://www.keyelco.com/product-pdf.cfm?p=1357 - Role: Terminal - Silkscreen Label: TP1 - Role Details: Test pad for net VBUS - Manufacturer Part Number: 5019 - Part Type: Test Point **Pins:** - 1 [pin 1] ### TP2 — [5019](https://www.flux.ai/adrian95/5019~fxh.md) - Part Type: Test Point - Role: Terminal - Manufacturer Part Number: 5019 - Silkscreen Label: TP2 - Package or Case Code: 5019 - Datasheet URL: https://www.keyelco.com/product-pdf.cfm?p=1357 - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Test pad for net D+ - Manufacturer Name: Keystone Electronics **Pins:** - 1 [pin 1] ### TP3 — [5019](https://www.flux.ai/adrian95/5019~fxh.md) - Manufacturer Part Number: 5019 - Part Type: Test Point - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.keyelco.com/product-pdf.cfm?p=1357 - Role Details: Test pad for net D- - Package or Case Code: 5019 - Silkscreen Label: TP3 - Manufacturer Name: Keystone Electronics - Role: Terminal **Pins:** - 1 [pin 1] ### TP4 — [5019](https://www.flux.ai/adrian95/5019~fxh.md) - Role Details: Test pad for net LATCH_ENABLE - Silkscreen Label: TP4 - Manufacturer Name: Keystone Electronics - Manufacturer Part Number: 5019 - Part Type: Test Point - Role: Terminal - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: 5019 - Datasheet URL: https://www.keyelco.com/product-pdf.cfm?p=1357 **Pins:** - 1 [pin 1] ### TP5 — [5019](https://www.flux.ai/adrian95/5019~fxh.md) - Manufacturer Part Number: 5019 - Part Type: Test Point - License: https://creativecommons.org/licenses/by/4.0/ - Silkscreen Label: TP5 - Datasheet URL: https://www.keyelco.com/product-pdf.cfm?p=1357 - Package or Case Code: 5019 - Role Details: Test pad for net TAMPER_TRIGGER - Role: Terminal - Manufacturer Name: Keystone Electronics **Pins:** - 1 [pin 1] ### U1 — [MP5016GQH-L-Z](https://www.flux.ai/monolithicpower/mp5016gqh-l-z~rxw.md) - Max Input Voltage: 5.5V - Product Image Url: https://www.monolithicpower.com/pub/media/catalog/product/m/p/mp5016-l_tac.jpg - Product Info Url: https://www.monolithicpower.com/en/catalog/product/view/id/2858?utm_source=ultralibrarian&utm_medium=component_search&utm_campaign=listing - Role Details: Reverse-current blocking load switch for USB VBUS - Manufacturer Part Number: MP5016GQH-L-Z - Package or Case Code: QFN10-1p5X2_MNP - Manufacturer Name: Monolithic Power Systems - Datasheet URL: https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP5016-L - Role: Protection **Pins:** - DV/DT [pin 10] - EN [pin 9] - GATE [pin 8] - GND [pin 3] - ILIMIT [pin 4] - MODE [pin 5] - SOURCE [pin 7] - SOURCE [pin 6] - VCC [pin 1] - VCC [pin 2] ### U1 — [MP5016GQH-L-Z](https://www.flux.ai/monolithicpower/mp5016gqh-l-z~rxw.md) - Manufacturer Name: Monolithic Power Systems - Package or Case Code: QFN10-1p5X2_MNP - Datasheet URL: https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP5016-L - Role: Protection - Manufacturer Part Number: MP5016GQH-L-Z - Product Image Url: https://www.monolithicpower.com/pub/media/catalog/product/m/p/mp5016-l_tac.jpg - Product Info Url: https://www.monolithicpower.com/en/catalog/product/view/id/2858?utm_source=ultralibrarian&utm_medium=component_search&utm_campaign=listing - Role Details: Reverse-current blocking load switch for USB VBUS **Pins:** - DV/DT [pin 10] - EN [pin 9] - GATE [pin 8] - GND [pin 3] - ILIMIT [pin 4] - MODE [pin 5] - SOURCE [pin 7] - SOURCE [pin 6] - VCC [pin 1] - VCC [pin 2] ### U2 — [LTC6993IS6-3#TRPBF](https://www.flux.ai/vasyl/ltc6993is6-3trpbf~ths.md) - Role Details: One-shot latch controller for tamper detection - Manufacturer Part Number: LTC6993IS6-3#TRPBF - Part Type: Integrated Circuit - Role: Latch - Manufacturer Name: Analog Devices Inc. - Datasheet URL: https://www.analog.com/media/en/technical-documentation/data-sheets/LTC6993-6993-1-6993-2-6993-3-6993-4.pdf **Pins:** - DIV [pin 4] - GND [pin 2] - OUT [pin 6] - SET [pin 3] - TRIG [pin 1] - V+ [pin 5] ### U2 — [LTC6993IS6-3#TRPBF](https://www.flux.ai/vasyl/ltc6993is6-3trpbf~ths.md) - Datasheet URL: https://www.analog.com/media/en/technical-documentation/data-sheets/LTC6993-6993-1-6993-2-6993-3-6993-4.pdf - Manufacturer Name: Analog Devices Inc. - Role Details: One-shot latch controller for tamper detection - Part Type: Integrated Circuit - Manufacturer Part Number: LTC6993IS6-3#TRPBF - Role: Latch **Pins:** - DIV [pin 4] - GND [pin 2] - OUT [pin 6] - SET [pin 3] - TRIG [pin 1] - V+ [pin 5] ### U3 — [LTC3625IDE-1#PBF](https://www.flux.ai/adrian95/ltc3625ide-1pbf~ya.md) - Datasheet URL: https://www.analog.com/media/en/technical-documentation/data-sheets/3625f.pdf - Role: Power Management - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: LTC3625IDE-1#PBF - Manufacturer Name: Analog Devices Inc. - Role Details: Supercapacitor charge controller for one-shot circuit - Part Type: Integrated Circuit **Pins:** - *PFO [pin 8] - CTL [pin 3] - EN [pin 5] - EPAD [pin 13] - PFI [pin 7] - PGOOD [pin 9] - PROG [pin 6] - SW1 [pin 1] - SW2 [pin 12] - VIN [pin 2] - VMID [pin 10] - VOUT [pin 11] - VSEL [pin 4] ### U3 — [LTC3625IDE-1#PBF](https://www.flux.ai/adrian95/ltc3625ide-1pbf~ya.md) - Role: Power Management - Part Type: Integrated Circuit - Datasheet URL: https://www.analog.com/media/en/technical-documentation/data-sheets/3625f.pdf - Manufacturer Part Number: LTC3625IDE-1#PBF - Role Details: Supercapacitor charge controller for one-shot circuit - Manufacturer Name: Analog Devices Inc. - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - *PFO [pin 8] - CTL [pin 3] - EN [pin 5] - EPAD [pin 13] - PFI [pin 7] - PGOOD [pin 9] - PROG [pin 6] - SW1 [pin 1] - SW2 [pin 12] - VIN [pin 2] - VMID [pin 10] - VOUT [pin 11] - VSEL [pin 4] ### U4 — [TPD3S014TDBVRQ1](https://www.flux.ai/vasy_skral/tpd3s014tdbvrq1~wzi.md) - Datasheet URL: http://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=http%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftpd3s014-q1 - Role Details: Switching device to short USB D+/D− lines on tamper trigger - Role: Switching - Manufacturer Name: Texas Instruments - Part Type: Protection - Manufacturer Part Number: TPD3S014TDBVRQ1 **Pins:** - D1 [pin 5] - D2 [pin 6] - EN [pin 1] - GND [pin 2] - IN [pin 3] - OUT [pin 4] ### U4 — [TPD3S014TDBVRQ1](https://www.flux.ai/vasy_skral/tpd3s014tdbvrq1~wzi.md) - Manufacturer Name: Texas Instruments - Part Type: Protection - Manufacturer Part Number: TPD3S014TDBVRQ1 - Role Details: MOSFET network shunt switch for D+/D 0 lines on tamper detection - Role: Switching - Datasheet URL: http://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=http%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftpd3s014-q1 **Pins:** - D1 [pin 5] - D2 [pin 6] - EN [pin 1] - GND [pin 2] - IN [pin 3] - OUT [pin 4] ### U5 — [USBLC6-2P6](https://www.flux.ai/kicad-part-library/usblc6-2p6~djt.md) - Role: Protection - Manufacturer Part Number: USBLC6-2P6 - Role Details: USB 2.0 ESD protection array for D+ and D− lines - Package or Case Code: SOT-666 - Manufacturer Name: Texas Instruments Inc. - Datasheet URL: https://www.st.com/resource/en/datasheet/usblc6-2.pdf **Pins:** - GND [pin 2] - I/O1 [pin 6] - I/O1 [pin 1] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### U5 — [USBLC6-2P6](https://www.flux.ai/kicad-part-library/usblc6-2p6~djt.md) - Package or Case Code: SOT-666 - Manufacturer Name: Texas Instruments Inc. - Datasheet URL: https://www.st.com/resource/en/datasheet/usblc6-2.pdf - Manufacturer Part Number: USBLC6-2P6 - Role Details: USB 2.0 ESD protection for D+, D−, and VBUS lines - Role: Protection **Pins:** - GND [pin 2] - I/O1 [pin 6] - I/O1 [pin 1] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### U6 — [TPD3S014TDBVRQ1](https://www.flux.ai/vasy_skral/tpd3s014tdbvrq1~wzi.md) - Role: Protection - Datasheet URL: http://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=http%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftpd3s014-q1 - Manufacturer Name: Texas Instruments - Part Type: Protection - Manufacturer Part Number: TPD3S014TDBVRQ1 - Role Details: Low-capacitance ESD TVS protection for USB lines **Pins:** - D1 [pin 5] - D2 [pin 6] - EN [pin 1] - GND [pin 2] - IN [pin 3] - OUT [pin 4] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/sapphirelinux/relieved-red-power-laces~kz](https://www.flux.ai/sapphirelinux/relieved-red-power-laces~kz).* --- *Generated from [https://www.flux.ai/sapphirelinux/relieved-red-power-laces~kz](https://www.flux.ai/sapphirelinux/relieved-red-power-laces~kz)*