# ALP2-BRIDGE ## Description Compact ESP32-S3 USB-to-WiFi bridge with USB-A programming/host data, USB-C charging input, LiPo power path, 3.3V buck, and 5V boost ## Project Details - **Owner:** derchb - **Created:** 5/9/2026 - **Last Updated:** 6/11/2026 - **Visibility:** Public ## Key Components ### D1 — [SML-D13FWT86C](https://www.flux.ai/jecstronic/sml-d13fwt86c~i2q.md) - Functional Group: Battery Charger & Power Path - Manufacturer Part Number: SML-D13FWT86C - Datasheet URL: https://fscdn.rohm.com/en/products/databook/datasheet/opto/led/chip_mono/sml-d13fwt86(c)-e.pdf - Role: Indicator - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Status LED indicator - Manufacturer Name: Rohm Semiconductor - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### D2 — [SML-D13FWT86C](https://www.flux.ai/jecstronic/sml-d13fwt86c~i2q.md) - Manufacturer Part Number: SML-D13FWT86C - Functional Group: Battery Charger & Power Path - Datasheet URL: https://fscdn.rohm.com/en/products/databook/datasheet/opto/led/chip_mono/sml-d13fwt86(c)-e.pdf - Role Details: Status LED indicator - Manufacturer Name: Rohm Semiconductor - Part Type: LED - Role: Indicator - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - A [pin 2] - K [pin 1] ### D3 — [SML-D13FWT86C](https://www.flux.ai/jecstronic/sml-d13fwt86c~i2q.md) - Manufacturer Part Number: SML-D13FWT86C - Datasheet URL: https://fscdn.rohm.com/en/products/databook/datasheet/opto/led/chip_mono/sml-d13fwt86(c)-e.pdf - Role: Indicator - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Status LED indicator - Manufacturer Name: Rohm Semiconductor - Functional Group: ESP32-S3 Controller - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### D4 — [TPD2EUSB30](https://www.flux.ai/kicad-part-library/tpd2eusb30~px7.md) - Role: ESD Protection - Role Details: USB D+/D- ESD clamp to ground at connector - Functional Group: USB-A Data Interface - Datasheet URL: http://www.ti.com/lit/ds/symlink/tpd2eusb30a.pdf - Package or Case Code: Texas_DRT-3 - Manufacturer Part Number: TPD2EUSB30 - Manufacturer Name: Texas Instruments Inc. **Pins:** - D- [pin 2] - D+ [pin 1] - GND [pin 3] ### D5 — [TPD2EUSB30](https://www.flux.ai/kicad-part-library/tpd2eusb30~px7.md) - Manufacturer Name: Texas Instruments Inc. - Functional Group: USB-A Data Interface - Datasheet URL: http://www.ti.com/lit/ds/symlink/tpd2eusb30a.pdf - Package or Case Code: Texas_DRT-3 - Role Details: USB D+/D- ESD clamp to ground at connector - Manufacturer Part Number: TPD2EUSB30 - Role: ESD Protection **Pins:** - D- [pin 2] - D+ [pin 1] - GND [pin 3] ### J1 — [USB-C 2.0 Receptacle](https://www.flux.ai/vasy_skral/usb-c-2p0-receptacle~1xw.md) - Manufacturer Name: GTC - Part Type: USB C - Symbol Style: parametric-v1 - Datasheet URL: https://gct.co/files/drawings/usb4105.pdf - Role Details: USB-C sink for 5V charging/input power only; ESP32 programming/debug now uses the USB-A data connector via native USB on GPIO19/GPIO20. - Purchase Url: https://www.digikey.com/en/products/detail/gct/USB4105-GF-A/11198441 - Manufacturer Part Number: USB4105-GF-A - Functional Group: USB-C Charge Input - Role: USB-C Charge Input **Pins:** - CC1 [pin 6] - CC2 [pin 12] - D- [pin 7] - D- [pin 9] - D+ [pin 10] - D+ [pin 8] - GND [pin 1] - GND [pin 16] - GND [pin 15] - GND [pin 2] - SBU1 [pin 11] - SBU2 [pin 5] - VBUS [pin 3] - VBUS [pin 14] - VBUS [pin 4] - VBUS [pin 13] ### J2 — [USB1015-GF-L-A](https://www.flux.ai/adrian95/usb1015-gf-l-a~0sl.md) - Role: USB-A Host and Programming Connector - Role Details: USB-A receptacle carries ESP32-S3 native USB D+/D- for LifePoint host mode and firmware programming/debug. During programming, keep 5V_HOST boost disabled or use a data-only/safe programming adapter to avoid VBUS backfeed against a PC host. - Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/5335/USB1015_Spec.pdf - Functional Group: USB-A Data Interface - Manufacturer Name: GCT - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Manufacturer Part Number: USB1015-GF-L-A **Pins:** - D- [pin 2] - D+ [pin 3] - GND [pin 4] - SHIELD [pin SH1] - SHIELD__1 [pin SH2] - SHIELD__2 [pin SH3] - SHIELD__3 [pin SH4] - VBUS [pin 1] ### J3 — [S2B-PH-SM4-TB(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-sm4-tblfsn~b96.md) - Role Details: Single-cell 3000mAh LiPo JST-PH connector - Role: Battery Connector - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: S2B-PH-SM4-TB(LF)(SN) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Functional Group: Battery Charger & Power Path - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### JP1 — [5-146256-2](https://www.flux.ai/adrian95/5-146256-2~qmp.md) - Role: Legacy USB-C Programming Jumper / DNI - Part Type: Connector - Role Details: Not required for normal programming because USB-A D+/D- connect directly to ESP32 GPIO19/GPIO20. Leave unpopulated unless a USB-C programming option is explicitly needed; do not connect USB-C and USB-A hosts simultaneously. - Datasheet URL: https://www.te.com/usa-en/product-5-146256-2.datasheet.pdf - Manufacturer Name: TE Connectivity - Package or Case Code: HDRV4W77P254_2X2_467X488X821P - Manufacturer Part Number: 5-146256-2 - License: https://creativecommons.org/licenses/by/4.0/ - Functional Group: USB-A Data Interface **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] ### SW1 — [PTS636 SM43J SMTR LFS](https://www.flux.ai/jharwinbarrozo/pts636-sm43j-smtr-lfs~6r0.md) - Role: User Button - Role Details: ESP32 BOOT or RESET momentary switch to ground - Datasheet URL: https://www.ckswitches.com/media/2779/pts636.pdf - Part Type: Switch - Manufacturer Name: C&K - Manufacturer Part Number: PTS636 SM43J SMTR LFS - Functional Group: ESP32-S3 Controller **Pins:** - P1 [pin 1] - P2 [pin 2] ### SW2 — [PTS636 SM43J SMTR LFS](https://www.flux.ai/jharwinbarrozo/pts636-sm43j-smtr-lfs~6r0.md) - Manufacturer Name: C&K - Manufacturer Part Number: PTS636 SM43J SMTR LFS - Part Type: Switch - Role Details: ESP32 BOOT or RESET momentary switch to ground - Role: User Button - Functional Group: ESP32-S3 Controller - Datasheet URL: https://www.ckswitches.com/media/2779/pts636.pdf **Pins:** - P1 [pin 1] - P2 [pin 2] ### SW3 — [MST-12D18G4 SPDT Slide Switch](https://www.flux.ai/adrian95/mst-12d18g4-spdt-slide-switch~zaw.md) - Voltage Rating: 12V - Part Type: Slide Switches - Current Rating: 100mA - Throw Configuration: Single Pole Double Throw (SPDT) - Role Details: User slide switch controlling system/host power enable path - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: SW-TH_SS-12D10L5 - Role: Power Switch - Manufacturer Part Number: MST-12D18G4 SPDT Slide Switch - Manufacturer Name: SHOU HAN - Datasheet URL: https://www.lcsc.com/datasheet/C49023767.pdf - Functional Group: 5 V Host Boost Supply - LCSC Part Number: C49023767 - Product Info Url: https://www.lcsc.com/product-detail/C49023767.html?utm_source=octopart&utm_medium=cpc&utm_campaign=MST-12D18G4%20SPDT%20Slide%20Switch **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### U1 — [ESP32-S3-WROOM-1-N16R8](https://www.flux.ai/adrian95/esp32-s3-wroom-1-n16r8~fs1.md) - Datasheet URL: https://www.mouser.com/datasheet/2/891/esp32_s3_wroom_1_wroom_1u_datasheet_en-2930317.pdf - Manufacturer Part Number: ESP32-S3-WROOM-1-N16R8 - Manufacturer Name: Espressif Systems - Role Details: ESP32-S3 WiFi bridge controller, native USB OTG on GPIO19/GPIO20 - Role: MCU Module - Functional Group: ESP32-S3 Controller - License: https://creativecommons.org/licenses/by/4.0/ - Symbol Style: parametric-v1 - Part Type: Module **Pins:** - 3V3 [pin 2] - EN [pin 3] - GND_1 [pin 1] - GND_10 [pin 48] - GND_11 [pin 49] - GND_2 [pin 40] - GND_3 [pin 41] - GND_4 [pin 42] - GND_5 [pin 43] - GND_6 [pin 44] - GND_7 [pin 45] - GND_8 [pin 46] - GND_9 [pin 47] - IO0 [pin 27] - IO1 [pin 39] - IO10 [pin 18] - IO11 [pin 19] - IO12 [pin 20] - IO13 [pin 21] - IO14 [pin 22] - IO15 [pin 8] - IO16 [pin 9] - IO17 [pin 10] - IO18 [pin 11] - IO19 [pin 13] - IO2 [pin 38] - IO20 [pin 14] - IO21 [pin 23] - IO3 [pin 15] - IO35 [pin 28] - IO36 [pin 29] - IO37 [pin 30] - IO38 [pin 31] - IO39 [pin 32] - IO4 [pin 4] - IO40 [pin 33] - IO41 [pin 34] - IO42 [pin 35] - IO45 [pin 26] - IO46 [pin 16] - IO47 [pin 24] - IO48 [pin 25] - IO5 [pin 5] - IO6 [pin 6] - IO7 [pin 7] - IO8 [pin 12] - IO9 [pin 17] - RXD0 [pin 36] - TXD0 [pin 37] ### U2 — [BQ24074RGTT](https://www.flux.ai/lcsc/bq24074rgtt~fpyl.md) - Package or Case Code: VQFN-16_L3.0-W3.0-P0.50-TL-EP1.7 - Symbol Style: parametric-v1 - Package: VQFN-16 RGT (3 mm × 3 mm) with exposed thermal pad - Operating Temperature: -40 to 85°C - Operating Voltage: IN operating range 4.35–10.2 V for BQ24074; IN withstand/recommended range up to 26 V, abs max 28 V - Role Details: BQ24074 USB input charger/power-path for 1S LiPo and SYS rail - Manufacturer Part Number: BQ24074RGTT - JLCPCB Part Class: Extended Part - Implementation Details: Standalone single-cell Li-Ion/Li-Polymer linear charger and power-path management IC; 4.2 V battery regulation, 4.4 V OUT regulation, 10.5 V OVP, 1.5 A programmable fast charge/input current limit. - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Texas Instruments - Datasheet URL: https://www.ti.com/lit/ds/symlink/bq24074.pdf - Part Type: Battery Management ICs - Functional Group: Battery Charger & Power Path - Role: Battery Charger Power Path - LCSC Part Number: C2861252 **Pins:** - ~{CE} [pin 4] - ~{CHG} [pin 9] - ~{PGOOD} [pin 7] - BAT [pin 2] - BAT [pin 3] - EN1 [pin 6] - EN2 [pin 5] - EP [pin 17] - ILIM [pin 12] - IN [pin 13] - ISET [pin 16] - ITERM [pin 15] - OUT [pin 11] - OUT [pin 10] - TMR [pin 14] - TS [pin 1] - VSS [pin 8] ### U3 — [TPS62840DLCR](https://www.flux.ai/lcsc/tps62840dlcr~fpxf.md) - LCSC Part Number: C2071859 - Functional Group: 3.3 V Buck Regulator - Part Type: DC-DC Converters - Manufacturer Name: TI(德州仪器) - Role: 3.3V Buck Regulator - Datasheet URL: https://www.lcsc.com/datasheet/C2071859.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNRTlhaX1NSQlVfVzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D - Manufacturer Part Number: TPS62840DLCR - Package or Case Code: VSON-8_L2.0-W1.5-P0.50-BL - Symbol Style: parametric-v1 - JLCPCB Part Class: Extended Part - Role Details: TPS62840 generates 3V3 rail from BQ24074 SYS output - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - EN [pin 4] - GND [pin 1] - MODE [pin 3] - STOP [pin 6] - SW [pin 7] - VIN [pin 2] - VOS [pin 8] - VSET [pin 5] ### U4 — [TPS61023DRLR](https://www.flux.ai/lcsc/tps61023drlr~qygu.md) - Part Type: DC-DC Converters - Logic Function: Boost type - Output Current: 3A - Functional Group: 5 V Host Boost Supply - Package or Case Code: SOT-563_L1.6-W1.2-P0.50-LS1.6-BR - Role Details: TPS61023 generates switched 5V USB host VBUS enabled by ESP32 GPIO - Datasheet URL: https://www.ti.com/lit/ds/symlink/tps61023.pdf?HQS=dis-dk-null-digikeymode-dsf-pf-null-wwe&ts=1780366470639&ref_url=https%253A%252F%252Fwww.icbanq.com%252F - Operating Temperature: -40℃~+125℃@(TJ) - Manufacturer Name: TI(德州仪器) - Frequency: 1MHz - Max Input Voltage: 500mV~5.5V - License: https://creativecommons.org/licenses/by/4.0/ - Symbol Style: parametric-v1 - Role: 5V Boost Regulator - LCSC Part Number: C919459 - Max Output Voltage: 2.2~5.5V - Manufacturer Part Number: TPS61023DRLR - JLCPCB Part Class: Extended Part **Pins:** - EN [pin 2] - FB [pin 1] - GND [pin 4] - SW [pin 5] - VIN [pin 3] - VOUT [pin 6] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/derchb/alp2-bridge~0v](https://www.flux.ai/derchb/alp2-bridge~0v).* --- *Generated from [https://www.flux.ai/derchb/alp2-bridge~0v](https://www.flux.ai/derchb/alp2-bridge~0v)*