# HB PCB Design Final ## Description A simple fixed linear voltage regulator board that can provide 3.3V up to 1A output and could operate down to 1V input-to-output differential. #firstpcbFlux ## Project Details - **Owner:** zhechenzhao - **Created:** 4/21/2025 - **Last Updated:** 9/26/2025 - **Visibility:** Public - **Copies:** 1 ## Key Components ### BAT54C-G — [BAT54C-G](https://www.flux.ai/lcsc/bat54c-g.md) - JLCPCB Part Class: Extended Part - Product Info Url: https://lcsc.com/product-detail/Schottky-Barrier-Diodes-SBD_BAT54C_C164910.html - Part Type: Schottky Barrier Diodes (SBD) - Package or Case Code: SOT-23_L2.9-W1.3-P1.90-LS2.4-BR - Manufacturer Name: CJ(江苏长电/长晶) - Manufacturer Part Number: BAT54C-G - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/1809211019_Jiangsu-Changjing-Electronics-Technology-Co---Ltd--BAT54C-G_C164910.pdf - LCSC Part Number: C164910 **Pins:** - A1 [pin 1] - A2 [pin 2] - K [pin 3] ### Battery_1 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### Battery_2 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Name: JST Sales America Inc. - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector **Pins:** - P1 [pin 1] - P2 [pin 2] ### LED_Bat1 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_Bat2 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_J2 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M1 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M2 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M3 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M4 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M5 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M6 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M7 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### LED_M8 — [LED 0805 (2012 Metric)](https://www.flux.ai/vasyl/led-0805-2012-metric.md) - Part Type: LED **Pins:** - A [pin 2] - K [pin 1] ### M1 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### M2 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Name: JST Sales America Inc. - Part Type: Connector - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) **Pins:** - P1 [pin 1] - P2 [pin 2] ### M3 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Name: JST Sales America Inc. - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector **Pins:** - P1 [pin 1] - P2 [pin 2] ### M4 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### M5 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Part Type: Connector - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### M6 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### M7 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf **Pins:** - P1 [pin 1] - P2 [pin 2] ### M8 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### Portenta H7 ABX00042 — [Portenta H7 ABX00042](https://www.flux.ai/vasy_skral/portenta-h7-abx00042.md) - Manufacturer Part Number: ABX00042 - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/Arduino%20PDFs/Portenta_H7_Web.pdf - Exclude from PCB: false - Part Type: Evaluation Board - Manufacturer Name: Arduino **Pins:** - ~RESET [pin J1_73] - ADC_A0 [pin J2_73] - ADC_A1 [pin J2_75] - ADC_A2 [pin J2_77] - ADC_A3 [pin J2_79] - ADC_A4 [pin J2_74] - ADC_A5 [pin J2_76] - ADC_A6 [pin J2_78] - ADC_A7 [pin J2_80] - ADC_VREF- [pin J2_72] - ADC_VREF+ [pin J2_71] - BOOT_SOURCE [pin J2_3] - CAM_CLK [pin J2_20] - CAM_D0 [pin J2_16] - CAM_D1 [pin J2_14] - CAM_D2 [pin J2_12] - CAM_D3 [pin J2_10] - CAM_D4 [pin J2_8] - CAM_D5 [pin J2_6] - CAM_D6 [pin J2_4] - CAM_D7 [pin J2_2] - CAM_HS [pin J2_22] - CAM_VS [pin J2_18] - CAN1_RX [pin J1_51] - CAN1_TX [pin J1_49] - COINCELL [pin J2_7] - DMIC_CK [pin J1_66] - DMIC_D0 [pin J1_68] - DSI_CK- [pin J1_20] - DSI_CK+ [pin J1_18] - DSI_D0- [pin J1_16] - DSI_D0+ [pin J1_14] - DSI_D1- [pin J1_12] - DSI_D1+ [pin J1_10] - ETH_A- [pin J1_3] - ETH_A+ [pin J1_1] - ETH_B- [pin J1_7] - ETH_B+ [pin J1_5] - ETH_L1 [pin J1_17] - ETH_L2 [pin J1_19] - FORCE_BOOTLOADER [pin J2_1] - GND [pin J1_22] - GND [pin J1_42] - GND [pin J1_31] - GND [pin J1_47] - GND [pin J1_54] - GND_1 [pin J2_57] - GND_1 [pin J2_70] - GND_1 [pin J2_33] - GND_1 [pin J2_44] - GND_1 [pin J2_24] - GPIO_0 [pin J2_46] - GPIO_1 [pin J2_48] - GPIO_2 [pin J2_50] - GPIO_3 [pin J2_52] - GPIO_4 [pin J2_54] - GPIO_5 [pin J2_56] - GPIO_6 [pin J2_58] - I2C0_SCL [pin J1_46] - I2C0_SDA [pin J1_44] - I2C1_SCL [pin J1_45] - I2C1_SDA [pin J1_43] - I2C2_SCL [pin J2_47] - I2C2_SDA [pin J2_45] - I2S_DI [pin J1_60] - I2S_DO [pin J1_62] - I2S_MCK [pin J1_56] - I2S_WS [pin J1_58] - NC [pin J1_80] - NC [pin J1_8] - NC [pin J1_78] - NC [pin J1_6] - NC [pin J1_9] - NC [pin J1_71] - NC [pin J1_69] - NC [pin J1_24] - NC [pin J1_50] - NC [pin J1_13] - NC [pin J1_2] - NC [pin J1_4] - NC [pin J1_76] - NC [pin J1_67] - NC [pin J1_30] - NC [pin J1_15] - NC [pin J1_70] - NC [pin J1_74] - NC [pin J1_11] - NC [pin J1_52] - NC_1 [pin J2_32] - NC_1 [pin J2_39] - NC_1 [pin J2_31] - NC_1 [pin J2_29] - NC_1 [pin J2_9] - NC_1 [pin J2_55] - NC_1 [pin J2_37] - NC_1 [pin J2_41] - NC_1 [pin J2_30] - NC_1 [pin J2_19] - NC_1 [pin J2_35] - NC_1 [pin J2_21] - NC_1 [pin J2_13] - NC_1 [pin J2_15] - NC_1 [pin J2_11] - NC_1 [pin J2_17] - POWER_ON_REQ [pin J2_5] - PWM_1 [pin J2_59] - PWM_10 [pin J2_68] - PWM_2 [pin J2_61] - PWM_3 [pin J2_63] - PWM_4 [pin J2_65] - PWM_5 [pin J2_67] - PWM_6 [pin J2_60] - PWM_7 [pin J2_62] - PWM_8 [pin J2_64] - PWM_9 [pin J2_66] - SAI_CK [pin J2_49] - SAI_D0 [pin J2_53] - SAI_FS [pin J2_51] - SDC_CLK [pin J1_55] - SDC_CMD [pin J1_57] - SDC_D0 [pin J1_59] - SDC_D1 [pin J1_61] - SDC_D2 [pin J1_63] - SDC_D3 [pin J1_65] - SPI1_CK [pin J2_38] - SPI1_CS [pin J2_36] - SPI1_MISO [pin J2_40] - SPI1_MOSI [pin J2_42] - SWCK [pin J1_77] - SWDIO [pin J1_75] - SWO [pin J1_79] - UART0_CTS [pin J1_40] - UART0_RTS [pin J1_38] - UART0_RX [pin J1_36] - UART0_TX [pin J1_34] - UART1_CTS [pin J1_39] - UART1_RTS [pin J1_37] - UART1_RX [pin J1_35] - UART1_TX [pin J1_33] - UART2_RX [pin J2_28] - UART2_TX [pin J2_26] - UART3_RX [pin J2_27] - UART3_TX [pin J2_25] - USB0_D- [pin J1_28] - USB0_D+ [pin J1_26] - USB1_D- [pin J1_27] - USB1_D+ [pin J1_25] - USB1_ID [pin J1_29] - USB1_VBUS [pin J1_23] - V-SDCARD [pin J1_72] - VCC [pin J2_34] - VCC/+3V3 [pin J2_23] - VCC/+3V3 [pin J2_69] - VCC/+3V3 [pin J2_43] - VIN [pin J1_48] - VIN [pin J1_21] - VIN [pin J1_41] - VIN [pin J1_32] - VSYS [pin J1_53] - VSYS [pin J1_64] ### Q1 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Part Number: MMST3904 - Part Type: Bipolar Transistors - BJT - JLCPCB Part Class: Extended Part - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL - LCSC Part Number: C2847224 - Manufacturer Name: BORN(伯恩半导体) **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q2 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Part Number: MMST3904 - Part Type: Bipolar Transistors - BJT - JLCPCB Part Class: Extended Part - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL - LCSC Part Number: C2847224 - Manufacturer Name: BORN(伯恩半导体) **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q3 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Name: BORN(伯恩半导体) - LCSC Part Number: C2847224 - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL - JLCPCB Part Class: Extended Part - Part Type: Bipolar Transistors - BJT - Manufacturer Part Number: MMST3904 **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q4 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - JLCPCB Part Class: Extended Part - Part Type: Bipolar Transistors - BJT - Manufacturer Part Number: MMST3904 - Manufacturer Name: BORN(伯恩半导体) - LCSC Part Number: C2847224 - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q5 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - JLCPCB Part Class: Extended Part - Part Type: Bipolar Transistors - BJT - Manufacturer Part Number: MMST3904 - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL - Manufacturer Name: BORN(伯恩半导体) - LCSC Part Number: C2847224 **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q6 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Part Number: MMST3904 - Part Type: Bipolar Transistors - BJT - JLCPCB Part Class: Extended Part - LCSC Part Number: C2847224 - Manufacturer Name: BORN(伯恩半导体) - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q7 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Part Number: MMST3904 - JLCPCB Part Class: Extended Part - Part Type: Bipolar Transistors - BJT - LCSC Part Number: C2847224 - Manufacturer Name: BORN(伯恩半导体) - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### Q8 — [MMST3904](https://www.flux.ai/lcsc/mmst3904.md) - Manufacturer Name: BORN(伯恩半导体) - LCSC Part Number: C2847224 - Package or Case Code: SOT-323-3_L2.1-W1.3-P1.30-LS2.3-BL - Part Type: Bipolar Transistors - BJT - JLCPCB Part Class: Extended Part - Manufacturer Part Number: MMST3904 **Pins:** - B [pin 1] - C [pin 3] - E [pin 2] ### S1 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S2 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S3 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S4 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Manufacturer Name: S4B-PH-K-S(LF)(SN) - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S5 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Manufacturer Name: S4B-PH-K-S(LF)(SN) - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S6 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S7 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### S8 — [S4B-PH-K-S(LF)(SN)](https://www.flux.ai/jecstronic/s4b-ph-k-slfsn.md) - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Part Number: S4B-PH-K-S(LF)(SN) - Manufacturer Name: S4B-PH-K-S(LF)(SN) **Pins:** - PIN_1 [pin 1] - PIN_2 [pin 2] - PIN_3 [pin 3] - PIN_4 [pin 4] ### TCA9548A — [TCA9548APWR](https://www.flux.ai/jecstronic/tca9548apwr.md) - Manufacturer Part Number: TCA9548APWR - Datasheet URL: https://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftca9548a - Part Type: Integrated Circuit - Manufacturer Name: Texas Instruments **Pins:** - ~RESET [pin 3] - A0 [pin 1] - A1 [pin 2] - A2 [pin 21] - GND [pin 12] - SC0 [pin 5] - SC1 [pin 7] - SC2 [pin 9] - SC3 [pin 11] - SC4 [pin 14] - SC5 [pin 16] - SC6 [pin 18] - SC7 [pin 20] - SCL [pin 22] - SD0 [pin 4] - SD1 [pin 6] - SD2 [pin 8] - SD3 [pin 10] - SD4 [pin 13] - SD5 [pin 15] - SD6 [pin 17] - SD7 [pin 19] - SDA [pin 23] - VCC [pin 24] ### U5 — [MPU-9250](https://www.flux.ai/adrian95/mpu-9250.md) - Manufacturer Name: TDK InvenSense - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Sensor - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/TDK%20PDFs/MPU-9250_Rev_1.1.pdf - Manufacturer Part Number: MPU-9250 **Pins:** - ~CS [pin 22] - AD0/SDO [pin 9] - AUX_CL [pin 7] - AUX_DA [pin 21] - EXP [pin 25] - FSYNC [pin 11] - GND [pin 18] - INT [pin 12] - NC [pin 15] - NC [pin 6] - NC [pin 17] - NC [pin 4] - NC [pin 3] - NC [pin 16] - NC [pin 2] - NC [pin 5] - NC [pin 14] - REGOUT [pin 10] - RESV_1 [pin 1] - RESV_19 [pin 19] - RESV_20 [pin 20] - SCL/SCLK [pin 23] - SDA/SDI [pin 24] - VDD [pin 13] - VDDIO [pin 8] ### ULN2803A — [ULN2803A](https://www.flux.ai/jecstronic/uln2803a.md) - Manufacturer Name: STMicroelectronics - Manufacturer Part Number: ULN2803A - Part Type: Transistor Array - Datasheet URL: https://www.st.com/content/ccc/resource/technical/document/datasheet/e4/fa/1c/16/4e/39/49/04/CD00000179.pdf/files/CD00000179.pdf/jcr:content/translations/en.CD00000179.pdf - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - COM [pin 10] - GND [pin 9] - I1 [pin 1] - I2 [pin 2] - I3 [pin 3] - I4 [pin 4] - I5 [pin 5] - I6 [pin 6] - I7 [pin 7] - I8 [pin 8] - O1 [pin 18] - O2 [pin 17] - O3 [pin 16] - O4 [pin 15] - O5 [pin 14] - O6 [pin 13] - O7 [pin 12] - O8 [pin 11] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/zhechenzhao/hb-pcb-design-final](https://www.flux.ai/zhechenzhao/hb-pcb-design-final).* --- *Generated from [https://www.flux.ai/zhechenzhao/hb-pcb-design-final](https://www.flux.ai/zhechenzhao/hb-pcb-design-final)*