# Light Pendant V2 ## Description 25 mm circular BLE wearable pendant for ambient-light tracking using an ISP1807 module, AS7343 sensor, USB-C LiPo charging, and SWD programming pads. ## Project Details - **Owner:** jeffenk - **Created:** 7/12/2026 - **Last Updated:** 7/28/2026 - **Visibility:** Public ## Key Components ### J2 — [SM02B-SRSS-TB(LF)(SN)](https://www.flux.ai/lcsc/sm02b-srss-tblfsn~89ny.md) - LCSC Part Number: C160402 - Role: Energy Storage - Voltage Rating: 50V - Connector Positions: 2 - Digi-Key Part Number: 455-1804-1-ND - Current Rating: 1A - Connector Gender: Male - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_JST-SM02B-SRSS-TB-LF-SN_C160402.pdf - Role Details: Exact right-angle JST SH SM02B-SRSS-TB(LF)(SN), 1.0 mm pitch, side-entry; mates with TinyCircuits ASR00011 70 mAh LiPo micro JST-SH/SHR-02V-S-B connector - Connector Type: Headers and Wire Housings - Manufacturer Part Number: SM02B-SRSS-TB(LF)(SN) - Package or Case Code: CONN-SMD_2P-P1.00_SM02B-SRSS-TB-LF-SN - Part Type: Wire To Board / Wire To Wire Connector - JLCPCB Part Class: Extended Part - Product Info Url: https://lcsc.com/product-detail/Others_JST-Sales-America__JST-Sales-America-SM02B-SRSS-TB-LF-SN_C160402.html - Manufacturer Name: JST - Connector Pitch: 1mm **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] ### U1 — ISP1907-HT - TB - Role Details: Top-side ISP1907-HT-JT; pin 17 is P1_00/TRACEDATA0 and is used as I2C_SCL_3V3; USB is unused so VBUS/D+/D- remain NC; maintain 18 mm x 4 mm antenna no-metal keepout on all layers - Manufacturer Name: Insight SiP - Package or Case Code: Module - Datasheet URL: https://www.insightsip.com/fichiers_insightsip/pdf/ble/ISP1907/isp_ble_DS1907.pdf - Part Type: Integrated Circuit - Integrated Circuit Type: RF Device - Role: BLE MCU Module - Manufacturer Part Number: ISP1907-HT-JT **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] - 17 [pin 17] - 18 [pin 18] - 19 [pin 19] - 2 [pin 2] - 20 [pin 20] - 21 [pin 21] - 22 [pin 22] - 23 [pin 23] - 24 [pin 24] - 25 [pin 25] - 26 [pin 26] - 27 [pin 27] - 28 [pin 28] - 29 [pin 29] - 3 [pin 3] - 30 [pin 30] - 31 [pin 31] - 32 [pin 32] - 33 [pin 33] - 34 [pin 34] - 35 [pin 35] - 36 [pin 36] - 37 [pin 37] - 38 [pin 38] - 39 [pin 39] - 4 [pin 4] - 40 [pin 40] - 41 [pin 41] - 42 [pin 42] - 43 [pin 43] - 44 [pin 44] - 45 [pin 45] - 46 [pin 46] - 47 [pin 47] - 48 [pin 48] - 49 [pin 49] - 5 [pin 5] - 50 [pin 50] - 51 [pin 51] - 52 [pin 52] - 53 [pin 53] - 54 [pin 54] - 55 [pin 55] - 56 [pin 56] - 57 [pin 57] - 58 [pin 58] - 59 [pin 59] - 6 [pin 6] - 60 [pin 60] - 61 [pin 61] - 62 [pin 62] - 7 [pin 7] - 8 [pin 8] - 9 [pin 9] ### U2 — [AS7343-DLGM](https://www.flux.ai/cherepanyadima/as7343-dlgm~h9.md) - Datasheet URL: https://www.snapeda.com/parts/AS7343-DLGM/ams%20OSRAM/datasheet/ - Role: Sensing (Shunt) - Manufacturer Name: ams-OSRAM USA INC. - Role Details: Top-side AS7343 on 1.8 V rail; optical aperture must remain unobstructed - Part Type: Sensor - Manufacturer Part Number: AS7343L-DLGM **Pins:** - GND [pin 3] - GPIO [pin 6] - INT [pin 7] - LDR [pin 4] - PGND [pin 5] - SCL [pin 2] - SDA [pin 8] - VDD [pin 1] ### U4 — [MCP1703Ax-330xxTT](https://www.flux.ai/kicad-part-library/mcp1703ax-330xxtt~9wn.md) - Role: Power Conversion - Manufacturer Name: Microchip Technology Inc. - Datasheet URL: http://ww1.microchip.com/downloads/en/DeviceDoc/20005122B.pdf - Role Details: LiPo BAT to 3V3, budgeted for BLE plus level shifter; rail may drop out near low battery - Manufacturer Part Number: MCP1703Ax-330xxTT - Package or Case Code: SOT-23 **Pins:** - GND [pin 1] - VI [pin 3] - VO [pin 2] ### U5 — [AP2112K-1.8TRG1](https://www.flux.ai/lcsc/ap2112k-1p8trg1~0t5p.md) - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_Diodes-Incorporated-AP2112K-1-8TRG1_C176944.pdf - Part Type: Linear Voltage Regulators (LDO) - Package or Case Code: SOT-25_L3.0-W1.6-P0.95-LS2.8-BL - Product Info Url: https://lcsc.com/product-detail/presales_Diodes-Incorporated-AP2112K-1-8TRG1_C176944.html - Manufacturer Part Number: AP2112K-1.8TRG1 - LCSC Part Number: C176944 - JLCPCB Part Class: Extended Part - Role: Power Conversion - Manufacturer Name: DIODES(美台) - Role Details: AS7343 1.8 V supply; EN tied high to BAT/enable source **Pins:** - EN [pin 3] - GND [pin 2] - NC [pin 4] - VIN [pin 1] - VOUT [pin 5] ### U6 — [TXS0102DCU](https://www.flux.ai/kicad-part-library/txs0102dcu~ql.md) - Manufacturer Part Number: TXS0102DCU - Package or Case Code: VSSOP-8_2.3x2mm_P0.5mm - Manufacturer Name: Texas Instruments Inc. - Datasheet URL: http://www.ti.com/lit/gpn/txs0102 - Role: Logic-level Shifting - Role Details: A side = 1V8 sensor bus, B side = 3V3 MCU bus; TXS0102 includes 10 kΩ pull-ups **Pins:** - A1 [pin 5] - A2 [pin 4] - B1 [pin 8] - B2 [pin 1] - GND [pin 2] - OE [pin 6] - VCCA [pin 3] - VCCB [pin 7] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/jeffenk/light-pendant-v2~28](https://www.flux.ai/jeffenk/light-pendant-v2~28).* --- *Generated from [https://www.flux.ai/jeffenk/light-pendant-v2~28](https://www.flux.ai/jeffenk/light-pendant-v2~28)*