# 4-Channel Gas Sensor AFE ## Description Four-channel electrochemical gas sensor signal-conditioning module based on the TI LMP91000EVM architecture, with shared I2C, per-channel SPI ADCs, 2.5V reference, sensor headers, and STM32F767ZI interface. ## Project Details - **Owner:** ximena123131 - **Created:** 6/24/2026 - **Last Updated:** 7/13/2026 - **Visibility:** Public ## Key Components ### J1 — [2.54-2*8P针](https://www.flux.ai/lcsc/2p54-28p~axke.md) - Manufacturer Name: BOOMELE(博穆精密) - Manufacturer Part Number: 2.54-2*8P针 - LCSC Part Number: C779499 - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: HDR-TH_16P-P2.54-V-M-R2-C8-S2.54 - Datasheet URL: https://www.lcsc.com/datasheet/C779499.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNeR1JcVFdURlJdUTsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D - JLCPCB Part Class: Extended Part - Part Type: Pin Headers - Symbol Style: parametric-v1 **Pins:** - 1 [pin 1] - 10 [pin 10] - 11 [pin 11] - 12 [pin 12] - 13 [pin 13] - 14 [pin 14] - 15 [pin 15] - 16 [pin 16] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] - 5 [pin 5] - 6 [pin 6] - 7 [pin 7] - 8 [pin 8] - 9 [pin 9] ### J2 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - Part Type: Connector - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Manufacturer Part Number: 61300311021 - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Wurth Elektronik **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J3 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - Manufacturer Name: Wurth Elektronik - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Manufacturer Part Number: 61300311021 - Part Type: Connector **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J4 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - Manufacturer Name: Wurth Elektronik - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Manufacturer Part Number: 61300311021 - Part Type: Connector **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J5 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Wurth Elektronik - Part Type: Connector - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Manufacturer Part Number: 61300311021 - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J6 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - Manufacturer Part Number: 61300311021 - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Part Type: Connector - Manufacturer Name: Wurth Elektronik - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J7 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Wurth Elektronik - Part Type: Connector - Manufacturer Part Number: 61300311021 - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J8 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Wurth Elektronik - Part Type: Connector - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Manufacturer Part Number: 61300311021 - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### JP1 — [61300311021](https://www.flux.ai/adrian95/61300311021~b2y.md) - Manufacturer Part Number: 61300311021 - Package or Case Code: HDRRA3W79P0X254_1X3_762X254X269P - Datasheet URL: https://www.we-online.com/components/products/datasheet/61300311021.pdf - Part Type: Connector - Manufacturer Name: Wurth Elektronik - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### Q1 — [MMBFJ177LT1G](https://www.flux.ai/adrian95/mmbfj177lt1g~0s8.md) - Role Details: Optional DNP JFET for RE-WE shorting when off - Datasheet URL: https://www.onsemi.com/pdf/datasheet/mmbfj177lt1-d.pdf - Part Type: Transistor - Manufacturer Part Number: MMBFJ177LT1G - Manufacturer Name: ON Semiconductor - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - D [pin 1] - G [pin 3] - S [pin 2] ### Q2 — [MMBFJ177LT1G](https://www.flux.ai/adrian95/mmbfj177lt1g~0s8.md) - Part Type: Transistor - Datasheet URL: https://www.onsemi.com/pdf/datasheet/mmbfj177lt1-d.pdf - Role Details: Optional DNP JFET for RE-WE shorting when off - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: MMBFJ177LT1G - Manufacturer Name: ON Semiconductor **Pins:** - D [pin 1] - G [pin 3] - S [pin 2] ### Q3 — [MMBFJ177LT1G](https://www.flux.ai/adrian95/mmbfj177lt1g~0s8.md) - Datasheet URL: https://www.onsemi.com/pdf/datasheet/mmbfj177lt1-d.pdf - Part Type: Transistor - Manufacturer Part Number: MMBFJ177LT1G - Manufacturer Name: ON Semiconductor - Role Details: Optional DNP JFET for RE-WE shorting when off - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - D [pin 1] - G [pin 3] - S [pin 2] ### Q4 — [MMBFJ177LT1G](https://www.flux.ai/adrian95/mmbfj177lt1g~0s8.md) - Manufacturer Name: ON Semiconductor - Manufacturer Part Number: MMBFJ177LT1G - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Optional DNP JFET for RE-WE shorting when off - Datasheet URL: https://www.onsemi.com/pdf/datasheet/mmbfj177lt1-d.pdf - Part Type: Transistor **Pins:** - D [pin 1] - G [pin 3] - S [pin 2] ### U1 — [LMP91000SDE/NOPB](https://www.flux.ai/adrian95/lmp91000sdenopb~d5k.md) - Manufacturer Part Number: LMP91000SDE/NOPB - Manufacturer Name: Texas Instruments - Part Type: Integrated Circuit - Datasheet URL: https://www.ti.com/lit/ds/symlink/lmp91000.pdf - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - AGND [pin 7] - C1 [pin 10] - C2 [pin 9] - CE [pin 14] - DGND [pin 1] - EP [pin 15] - MENB [pin 2] - NC [pin 5] - RE [pin 13] - SCL [pin 3] - SDA [pin 4] - VDD [pin 6] - VOUT [pin 8] - VREF [pin 11] - WE [pin 12] ### U2 — [LMP91000SDE/NOPB](https://www.flux.ai/adrian95/lmp91000sdenopb~d5k.md) - Part Type: Integrated Circuit - Manufacturer Name: Texas Instruments - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.ti.com/lit/ds/symlink/lmp91000.pdf - Manufacturer Part Number: LMP91000SDE/NOPB **Pins:** - AGND [pin 7] - C1 [pin 10] - C2 [pin 9] - CE [pin 14] - DGND [pin 1] - EP [pin 15] - MENB [pin 2] - NC [pin 5] - RE [pin 13] - SCL [pin 3] - SDA [pin 4] - VDD [pin 6] - VOUT [pin 8] - VREF [pin 11] - WE [pin 12] ### U3 — [LMP91000SDE/NOPB](https://www.flux.ai/adrian95/lmp91000sdenopb~d5k.md) - Manufacturer Part Number: LMP91000SDE/NOPB - Datasheet URL: https://www.ti.com/lit/ds/symlink/lmp91000.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Texas Instruments - Part Type: Integrated Circuit **Pins:** - AGND [pin 7] - C1 [pin 10] - C2 [pin 9] - CE [pin 14] - DGND [pin 1] - EP [pin 15] - MENB [pin 2] - NC [pin 5] - RE [pin 13] - SCL [pin 3] - SDA [pin 4] - VDD [pin 6] - VOUT [pin 8] - VREF [pin 11] - WE [pin 12] ### U4 — [LMP91000SDE/NOPB](https://www.flux.ai/adrian95/lmp91000sdenopb~d5k.md) - Manufacturer Name: Texas Instruments - Datasheet URL: https://www.ti.com/lit/ds/symlink/lmp91000.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Integrated Circuit - Manufacturer Part Number: LMP91000SDE/NOPB **Pins:** - AGND [pin 7] - C1 [pin 10] - C2 [pin 9] - CE [pin 14] - DGND [pin 1] - EP [pin 15] - MENB [pin 2] - NC [pin 5] - RE [pin 13] - SCL [pin 3] - SDA [pin 4] - VDD [pin 6] - VOUT [pin 8] - VREF [pin 11] - WE [pin 12] ### U5 — [ADS7866](https://www.flux.ai/kicad-part-library/ads7866~1g.md) - Manufacturer Part Number: ADS7866 - Datasheet URL: http://www.ti.com/lit/ds/symlink/ads7866.pdf - Package or Case Code: TSOT-23-6 - Role Details: Substitute for ADC161S626; verify resolution/pinout before fabrication - Manufacturer Name: Texas Instruments Inc. **Pins:** - ~{CS} [pin 6] - AIN [pin 3] - GND [pin 2] - SCLK [pin 4] - SDO [pin 5] - VDD [pin 1] ### U6 — [ADS7866](https://www.flux.ai/kicad-part-library/ads7866~1g.md) - Manufacturer Name: Texas Instruments Inc. - Package or Case Code: TSOT-23-6 - Role Details: Substitute for ADC161S626; verify resolution/pinout before fabrication - Datasheet URL: http://www.ti.com/lit/ds/symlink/ads7866.pdf - Manufacturer Part Number: ADS7866 **Pins:** - ~{CS} [pin 6] - AIN [pin 3] - GND [pin 2] - SCLK [pin 4] - SDO [pin 5] - VDD [pin 1] ### U7 — [ADS7866](https://www.flux.ai/kicad-part-library/ads7866~1g.md) - Role Details: Substitute for ADC161S626; verify resolution/pinout before fabrication - Manufacturer Part Number: ADS7866 - Datasheet URL: http://www.ti.com/lit/ds/symlink/ads7866.pdf - Package or Case Code: TSOT-23-6 - Manufacturer Name: Texas Instruments Inc. **Pins:** - ~{CS} [pin 6] - AIN [pin 3] - GND [pin 2] - SCLK [pin 4] - SDO [pin 5] - VDD [pin 1] ### U8 — [ADS7866](https://www.flux.ai/kicad-part-library/ads7866~1g.md) - Datasheet URL: http://www.ti.com/lit/ds/symlink/ads7866.pdf - Package or Case Code: TSOT-23-6 - Role Details: Substitute for ADC161S626; verify resolution/pinout before fabrication - Manufacturer Name: Texas Instruments Inc. - Manufacturer Part Number: ADS7866 **Pins:** - ~{CS} [pin 6] - AIN [pin 3] - GND [pin 2] - SCLK [pin 4] - SDO [pin 5] - VDD [pin 1] ### U9 — [LM4125AIM5-2.5](https://www.flux.ai/kicad-part-library/lm4125aim5-2p5~ebo.md) - Datasheet URL: http://www.ti.com/lit/ds/symlink/lm4125.pdf - Package or Case Code: SOT-23-5 - Manufacturer Name: Texas Instruments Inc. - Manufacturer Part Number: LM4125AIM5-2.5 **Pins:** - GND [pin 2] - NC [pin 1] - NC [pin 3] - Vin [pin 4] - Vout [pin 5] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/ximena123131/4-channel-gas-sensor-afe~0g](https://www.flux.ai/ximena123131/4-channel-gas-sensor-afe~0g).* --- *Generated from [https://www.flux.ai/ximena123131/4-channel-gas-sensor-afe~0g](https://www.flux.ai/ximena123131/4-channel-gas-sensor-afe~0g)*