Smart Relay Design for Fuel Pumps

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devxxx

Can you create a downloaded format for the following: Automotive Smart Fuel Pump Controller - Engineering Handoff A 12 V nominal automotive smart fuel pump power controller that reads the OEM FSCM analog output after the factory module, qualifies battery input above 12 V, drives a protected pump output, monitors current and temperature, and provides red/blue status indication plus a 5-second audible fault alert.
  1. Current project status Schematic status ERC clean No remaining: floating pins undriven nets single-pin nets pin-to-pin conflicts missing power shorted 2-pin parts PCB status Not signed off yet Remaining DRC/layout issues: 83 airwires 58 floating copper 1 overlapping copper Board stackup: 4-layer Board size: 160 mm x 100 mm Placed component count: 36 Placement density: low / generous board area
  2. Technical scope Product intent Replace a traditional fuel-pump relay with a protected solid-state controller Accept OEM FSCM analog command input Require battery input > 12 V before valid operation Prevent pump operation when battery input is invalid Limit pump current to 25 A Provide thermal protection by derating, not shutdown Provide: red fault indication blue normal-operation indication 5-second audible alert Field interface Main field connector: J1 Current project uses J1 as the schematic/layout placeholder for the intended Deutsch 4-way interface. High-current path J1 -> F1 -> U4 -> Q1 -> R5
  3. Functional requirements Power and enable behavior Battery input must be greater than 12 V for valid operation Below 12 V, controller must not synthesize the output floor Pump must be off at shutdown / zero valid command Protected battery input path is implemented around: F1 U4 D1 C6 Command following OEM analog command enters through J1 Input filtering path uses: R4 C5 Command drives the control path around U2 Current measurement / limit intent Current shunt: R5 Current sense amplifier: IC1 Design intent is 25 A max Current-sense architecture exists, but still needs final validation in the routed PCB context Thermal monitoring Temperature sensor: U3 Thermal behavior target: warn derate recover do not hard-shutdown during thermal stress unless a separate catastrophic condition requires it User indication Red fault path: D2 Q2 R6 R7 Blue status path: D3 Q4 R9 R10 Audible alert path: LS1 Q3 R8
  4. Implemented schematic blocks Implemented active parts
Gate driver U2 Input protection / surge controller U4 Main power MOSFET Q1 Undervoltage supervisor U1 Current-sense amplifier IC1 Temperature sensor U3 Red LED driver transistor Q2 Blue LED driver transistor Q4 Buzzer driver transistor Q3 Implemented named nets TEMP_SENSE RED_FAULT_RET BATT_FUSED LOW_GATE_UNUSED BLUE_STATUS_BASE CURR_REF UV_FAULT RED_FAULT_BASE U4_GATE GND BAT_MON U2_BOOTSTRAP BATT_IN_RAW CURR_SENSE_OUT BUZZER_BASE PUMP_OUT FSCM_CMD_FILT GATE_DRIVE VBAT_PROTECTED BUZZER_LOW FSCM_ANALOG_IN PUMP_SW RED_FAULT_SRC FAULT_REQ CURR_SENSE_P 5. Remaining errors / open issues A. PCB DRC blockers
Critical Airwires 83 Board is still unrouted/incompletely routed Critical Floating copper 58 Likely isolated vias/traces/copper objects Critical Overlapping copper 1 Needs direct PCB cleanup before signoff B. Layout / routing work still required
1 Fix overlap near F1 Remove or redraw offending copper segment 2 Route high-current path Start with J1 -> F1 -> U4 -> Q1 -> R5 3 Route current-sense and gate-drive group Keep IC1 close to R5; keep U2 close to Q1 4 Remove/reconnect floating copper Delete stray copper or connect intentional copper properly 5 Route remaining control/status nets Finish LED, buzzer, UV, and temp/fault paths 6 Final DRC pass Target: 0 overlap, 0 floating copper, 0 airwires 6. Best-practice PCB guidance for your engineering team This is the recommended order for PCB closure and signoff, consistent with staged PCB cleanup and export workflows Power routing priority J1 F1 U4 Q1 R5 Placement/routing guidance Keep the high-current path short, wide, and direct Keep IC1 physically close to R5 Keep U2 close to Q1 for gate-drive quality Keep analog/control circuitry away from the switching/current loop Remove all isolated copper before final signoff Re-run DRC after each cleanup stage 7. Known design notes / limitations Schematic baseline is currently the most stable part of the project PCB is not yet signoff-ready The connector in the current design is a placeholder implementation for the intended Deutsch interface: J1 There is no firmware deliverable in this project at present: no MCU firmware source no compiled binary no embedded software artifact This project is primarily: schematic PCB BOM review/DFM closure work 8. Downloadable files available now Documentation export Project PDF: automotive-smart-fuel-pump-controller.pdf BOM exports Flux BOM: automotive-smart-fuel-pump-controller-bom.csv
C1,C2,C3,C4,C7 5 0517655b-452d-4520-a493-00ec64f69067,324e3b63-49ec-4463-b81d-53c585d957a7,4510af4f-d37b-42bc-bba6-326fa2178b7a,e74ad60c-2de2-4f16-a834-7478b9a8cdf1,f8f318d6-0f0a-4b79-9c1c-78599ecd99a2 46707925-236f-106b-e676-afa2757aa1d6 Non-Polarized Capacitor, 100nF, SMD_0805_2012Metric Non-Polarized Capacitor Decoupling,Timing Local decoupling on protected battery rail after fuse and controller,Decoupling for current-sense amplifier supply,Undervoltage qualification debounce capacitor,Decoupling for undervoltage supervisor supply,Decoupling for gate driver supply V % 100nF SMD_0805_2012Metric C C5 1 cf4c4a5d-2de5-4e81-ad51-f27cc789562f 46707925-236f-106b-e676-afa2757aa1d6 Non-Polarized Capacitor, 10nF, SMD_0805_2012Metric Non-Polarized Capacitor Input Filter OEM analog command smoothing capacitor V % 10nF SMD_0805_2012Metric C C6 1 c440d32d-7a03-4a10-9000-034dfd7a6721 46707925-236f-106b-e676-afa2757aa1d6 Non-Polarized Capacitor, 10uF, SMD_0805_2012Metric Non-Polarized Capacitor Bulk Protected battery input bulk capacitor after connector-side protection V % 10uF SMD_0805_2012Metric C D1 1 f7a77ed8-9ea4-428b-8bd0-10d5e5a289cb ff88f987-ab9c-37bd-4eae-459c5aed0063 Diode, SMB Diode Surge Protection Automotive battery input transient clamp near field connector SM6T12A STMicroelectronics https://creativecommons.org/licenses/by/4.0/ SMB D D2 1 f072043d-0d81-4d25-9553-8926eb662f41 75ff6bcd-4e02-465e-957e-44d3baf23c10 LED, 1210 LED Fault Indicator Red LED for distinct persistent flashing fault indication APD3224SURCK-F01 Kingbright https://creativecommons.org/licenses/by/4.0/ 1.95V 1210 LED D3 1 62024296-5b42-44f3-87ce-ce7a246f0234 f90cb071-0aaa-4f2f-86e1-e8c44f714ad8 LED, 0805 LED Status Indicator Blue LED for normal operation and thermal derate indication KT-0805B C2293 Hubei KENTO Elec https://creativecommons.org/licenses/by/4.0/ 0805 LED F1 1 2ce2c284-e2d5-4a18-812d-350764a52624 9974e98c-6fb8-4915-8dff-019fdd9799f2 0297030.WXNV, 0297030WXNV 0297030.WXNV Input Fuse 30 A automotive input fuse between raw battery and protected input stage 0297030.WXNV LITTELFUSE https://creativecommons.org/licenses/by/4.0/ 0297030WXNV Blade F IC1 1 c66d9c98-12e8-4f53-a474-c81cef5cde31 7b5d3683-8842-f2f0-2219-8718d7cf62c0 Integrated Circuit, SON-8 Integrated Circuit Current Sense Automotive current-sense amplifier for pump current limit and fault detection INA240A3EDRQ1 Texas Instruments SON-8 IC J1 1 170c1894-f9bc-4ff7-ae08-5ae17d286d21 6f84e1cd-0933-40e8-b854-09baaecd5036 Connector, Through Hole Connector Field Interface Deutsch DTP 4-way placeholder: Pin 1 GND, Pin 2 BATT_IN, Pin 3 PUMP_OUT, Pin 4 FSCM_ANALOG_IN DT13-4P TE Connectivity Deutsch Connectors https://creativecommons.org/licenses/by/4.0/ Through Hole J Pin 1 GND, Pin 2 BATT_IN, Pin 3 PUMP_OUT, Pin 4 FSCM_ANALOG_IN LS1 1 0c0e5821-6a97-4a45-a89d-a686428336b4 450acd1c-dd80-43d2-9f9b-78cd8ecbe611 Buzzer, PKMCS1818E20A0R1 Buzzer Audible Alert Piezo transducer for 5-second qualified fault beeping PKMCS1818E20A0-R1 Murata Electronics https://creativecommons.org/licenses/by/4.0/ PKMCS1818E20A0R1 SMD LS Q1 1 30bd10a5-ec61-4b74-b290-6d2271d99396 5c851efc-d850-456b-aebb-2e6182596f29 , LFPAK88 Power Switch External low-loss PWM pump-stage MOSFET controlled by gate driver SQJQ160E Texas Instruments Inc. Configured as first-pass external PWM pump-stage MOSFET. Final gate topology and thermal/parallel-device decisions remain to be refined in next pass. LFPAK88 LFPAK88 Q Q2,Q3,Q4 3 13feb876-178e-41e1-a245-d29376f4d69a,d5bbbc85-e6c6-448a-a1ca-4c5f29afff81,f3b1ffaa-5cc5-4f14-957c-37e31047ba67 c89e6e33-04cc-4c16-9a33-027ec5b38bab Transistor, SOT-23 Transistor LED Driver,Buzzer Driver Low-side driver for blue status LED,Low-side driver for red fault LED flashing patterns,Low-side driver for 5-second qualified audible fault alert MMBT3904LT1G onsemi https://creativecommons.org/licenses/by/4.0/ SOT-23 Q R1,R11,R12,R13,R14,R2 6 2f09bbb3-053e-40bb-8b9f-94bd4adac92a,3b44f7a6-ce1c-4100-8f3d-0429285a6256,62d4917e-13d2-48a6-ac02-53a62728e09a,c9786572-246f-4288-bef1-a13a37d4498c,d4338506-0306-4ddf-999c-de73b0536cd2,f801cfde-01bf-40e7-b2a1-4c502ebca32f b67f50a9-ae5e-10ea-9c3c-d377e2ab3b2d Resistor, 100kΩ, SMD_0805_2012Metric Resistor Feedback,Fault Sense Link,Pull Down Battery sense divider upper resistor A,Battery sense divider upper resistor B / command scaling option,Weak coupling from U1 reset/UV output to FAULT_REQ/monitor path to eliminate isolated undervoltage fault net while preserving supervisor ownership,Weak coupling from TEMP_SENSE to FAULT_REQ/monitor path to prevent floating temperature-control net during ERC repair pass,Terminates isolated U4 gate node U4_GATE to ground during protected-input controller refinement,Terminates unused U2 LO output net LOW_GATE_UNUSED to ground to prevent floating/undriven control state V 100kΩ % SMD_0805_2012Metric R R3,R4 2 8e03fd44-0b12-410d-ac9e-3ba60fcc5067,a5926437-5cec-4ae3-bc40-8bbf64939b56 b67f50a9-ae5e-10ea-9c3c-d377e2ab3b2d Resistor, 10kΩ, SMD_0805_2012Metric Resistor Input Filter,Feedback OEM FSCM analog input series/filter resistor,Battery sense divider lower resistor V 10kΩ % SMD_0805_2012Metric R R5 1 949e576d-951a-4f77-b08f-606855646f09 f0617ba8-f91a-482b-8822-9b39748fc8f4 , 2512 Current Sense 25A pump-path shunt for INA240 current measurement and protection monitoring PU2512FKGP60U5L 500uΩ 2512 R R6,R9 2 04e8b9a7-497d-4d16-896c-0ae3749a23e1,769d46ec-3027-465c-b814-09ff9ab115c5 b67f50a9-ae5e-10ea-9c3c-d377e2ab3b2d Resistor, 1kΩ, SMD_0805_2012Metric Resistor Current Limit Series resistor for blue status LED D3,Series current-limiting resistor for red fault LED V 1kΩ % SMD_0805_2012Metric R R10,R7,R8 3 2bfa6fd3-e840-4e98-9d56-fe588a5495cc,3a3e0844-8f30-442d-9adb-a1242f56d8d3,d9be538b-536c-4c2e-8c13-5792dd6fade5 b67f50a9-ae5e-10ea-9c3c-d377e2ab3b2d Resistor, 4.7kΩ, SMD_0805_2012Metric Resistor Base Drive Base resistor for blue LED driver transistor Q4,Base resistor for buzzer driver transistor Q3,Base resistor for red LED driver transistor Q2 V 4.7kΩ % SMD_0805_2012Metric R U1 1 452a57a0-986d-40be-8d87-a85938815a00 b821d1e7-1574-4a6a-b4a8-2a81c31d05c9 , SOIC-8_3.9x4.9mm_P1.27mm Undervoltage Supervisor Battery qualification and undervoltage fault generation for strict >12V operation MC34064D SOIC-8_3.9x4.9mm_P1.27mm SOIC-8 U U2 1 03534adc-81d2-424e-9b63-34c7d16ceacc 3ff7ca3f-771e-3cc2-8ff3-33d033c67dc6 Integrated Circuit, SOIC-8 Integrated Circuit Gate Driver Half-bridge PWM gate driver for external high-current MOSFET power stage UCC27714D Texas Instruments https://creativecommons.org/licenses/by/4.0/ SOIC-8 U U3 1 e92ac55e-5927-41ba-bde1-fd8d55c5de7a 05216e12-201c-4d6a-98a5-36015ed93312 Integrated Circuit, SC70-5 Integrated Circuit Temperature Sense Hotspot analog temperature sensor for thermal derating and recovery TMP235A4DCKR Texas Instruments https://creativecommons.org/licenses/by/4.0/ SC70-5 U U4 1 2e2a705a-0136-43af-972a-7b05ea4d650f 424fec08-32bc-475d-bfbf-f6cbb78ada2d Integrated Circuit, MSOP-12 Integrated Circuit Input Protection Protected battery input controller for surge, reverse, and undervoltage-aware front-end path LT4363IMS-2#PBF Analog Devices Inc. Temporary first-pass wiring: connector-facing surge/hot-swap controller tied into protected battery path. UV/OV/FB are temporarily referenced to protected output pending final threshold network refinement. https://creativecommons.org/licenses/by/4.0/ MSOP-12 IC JLCPCB BOM: automotive-smart-fuel-pump-controller-bom-jlcpcb.csv
Non-Polarized Capacitor 100nF SMD_0805_2012Metric C1, C2, C3, C4, C7 Non-Polarized Capacitor 10nF SMD_0805_2012Metric C5 Non-Polarized Capacitor 10uF SMD_0805_2012Metric C6 SM6T12A D1 APD3224SURCK-F01 D2 KT-0805B D3 C2293 0297030.WXNV F1 0297030WXNV INA240A3EDRQ1 IC1 DT13-4P J1 PKMCS1818E20A0-R1 LS1 PKMCS1818E20A0R1 SQJQ160E Q1 LFPAK88 MMBT3904LT1G Q2, Q3, Q4 Resistor 100kΩ SMD_0805_2012Metric R1, R11, R12, R13, R14, R2 Resistor 10kΩ SMD_0805_2012Metric R3, R4 PU2512FKGP60U5L R5 Resistor 1kΩ SMD_0805_2012Metric R6, R9 Resistor 4.7kΩ SMD_0805_2012Metric R10, R7, R8 MC34064D U1 SOIC-8_3.9x4.9mm_P1.27mm UCC27714D U2 TMP235A4DCKR U3 LT4363IMS-2#PBF U4 PCBWay BOM: automotive-smart-fuel-pump-controller-bom-pcbway.csv
1 C1,C2,C3,C4,C7 5 Non-Polarized Capacitor, 100nF, SMD_0805_2012Metric 2 C5 1 Non-Polarized Capacitor, 10nF, SMD_0805_2012Metric 3 C6 1 Non-Polarized Capacitor, 10uF, SMD_0805_2012Metric 4 D1 1 STMicroelectronics SM6T12A Diode, SMB 5 D2 1 Kingbright APD3224SURCK-F01 LED, 1210 6 D3 1 Hubei KENTO Elec KT-0805B LED, 0805 7 F1 1 LITTELFUSE 0297030.WXNV 0297030.WXNV, 0297030WXNV 0297030WXNV 8 IC1 1 Texas Instruments INA240A3EDRQ1 Integrated Circuit, SON-8 9 J1 1 TE Connectivity Deutsch Connectors DT13-4P Connector, Through Hole 10 LS1 1 Murata Electronics PKMCS1818E20A0-R1 Buzzer, PKMCS1818E20A0R1 PKMCS1818E20A0R1 11 Q1 1 Texas Instruments Inc. SQJQ160E , LFPAK88 LFPAK88 12 Q2,Q3,Q4 3 onsemi MMBT3904LT1G Transistor, SOT-23 13 R1,R11,R12,R13,R14,R2 6 Resistor, 100kΩ, SMD_0805_2012Metric 14 R3,R4 2 Resistor, 10kΩ, SMD_0805_2012Metric 15 R5 1 PU2512FKGP60U5L , 2512 16 R6,R9 2 Resistor, 1kΩ, SMD_0805_2012Metric 17 R10,R7,R8 3 Resistor, 4.7kΩ, SMD_0805_2012Metric 18 U1 1 MC34064D , SOIC-8_3.9x4.9mm_P1.27mm SOIC-8_3.9x4.9mm_P1.27mm 19 U2 1 Texas Instruments UCC27714D Integrated Circuit, SOIC-8 20 U3 1 Texas Instruments TMP235A4DCKR Integrated Circuit, SC70-5 21 U4 1 Analog Devices Inc. LT4363IMS-2#PBF Integrated Circuit, MSOP-12 Advanced Circuits BOM: automotive-smart-fuel-pump-controller-bom-advanced-circuits.csv
Non-Polarized Capacitor, 100nF, SMD_0805_2012Metric 5 C1,C2,C3,C4,C7 Non-Polarized Capacitor, 10nF, SMD_0805_2012Metric 1 C5 Non-Polarized Capacitor, 10uF, SMD_0805_2012Metric 1 C6 Diode, SMB 1 D1 SM6T12A STMicroelectronics LED, 1210 1 D2 APD3224SURCK-F01 Kingbright LED, 0805 1 D3 KT-0805B Hubei KENTO Elec 0297030.WXNV, 0297030WXNV 1 F1 0297030.WXNV LITTELFUSE Integrated Circuit, SON-8 1 IC1 INA240A3EDRQ1 Texas Instruments Connector, Through Hole 1 J1 DT13-4P TE Connectivity Deutsch Connectors Buzzer, PKMCS1818E20A0R1 1 LS1 PKMCS1818E20A0-R1 Murata Electronics , LFPAK88 1 Q1 SQJQ160E Texas Instruments Inc. Transistor, SOT-23 3 Q2,Q3,Q4 MMBT3904LT1G onsemi Resistor, 100kΩ, SMD_0805_2012Metric 6 R1,R11,R12,R13,R14,R2 Resistor, 10kΩ, SMD_0805_2012Metric 2 R3,R4 , 2512 1 R5 PU2512FKGP60U5L Resistor, 1kΩ, SMD_0805_2012Metric 2 R6,R9 Resistor, 4.7kΩ, SMD_0805_2012Metric 3 R10,R7,R8 , SOIC-8_3.9x4.9mm_P1.27mm 1 U1 MC34064D Integrated Circuit, SOIC-8 1 U2 UCC27714D Texas Instruments Integrated Circuit, SC70-5 1 U3 TMP235A4DCKR Texas Instruments Integrated Circuit, MSOP-12 1 U4 LT4363IMS-2#PBF Analog Devices Inc. 9. What is not yet downloadable Firmware: none exists in this project Production-ready PCB manufacturing pack: not recommended yet until PCB DRC is clean Signoff-ready release package: not yet, because the board is still unrouted / failing DRC
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    Automotive Smart Fuel Pump Controller thumbnail
    Automotive smart fuel pump controller with >12 V battery qualification, protected battery input, analog FSCM command following, 25 A current sensing, thermal/fault indication, blue/red LED signaling, and 5-second buzzer alert. Control and fault nets are explicitly terminated to avoid floating or undriven states; any intentionally provisional control nodes are weakly biased to safe defaults during refinement.

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    Qty 1

    Arrow

    $20.62–$24.63

    Digi-Key

    $27.03–$27.43

    LCSC

    $23.13–$23.14

    Mouser

    $29.43

    TME

    $5.01

    Verical

    $17.01–$30.04

    Controls