# Visible Light Sensor TIA ## Description Reverse-biased photodiode visible-light sensor with op-amp transimpedance amplifier, DIP-switch-selectable gain resistors, and output smoothing. ## Project Details - **Owner:** lmaples97 - **Created:** 5/16/2026 - **Last Updated:** 5/16/2026 - **Visibility:** Public ## Key Components ### D1 — [SFH203](https://www.flux.ai/vasy_skral/sfh203~kkg.md) - Role: Sensing (Shunt) - Manufacturer Name: OSRAM Opto Semiconductors Inc. - Role Details: SFH 203 photodiode; cathode biased from +5V and anode connected to the TIA summing node for reverse-biased current sensing. - Manufacturer Part Number: SFH 203 - Mouser Part Number: 720-SFH203 - Part Type: Photodiode - Datasheet URL: https://dammedia.osram.info/media/resource/hires/osram-dam-5488337/SFH%20203_EN.pdf **Pins:** - A [pin 2] - K [pin 1] ### J1 — [0022232031](https://www.flux.ai/adrian95/0022232031~ox7.md) - Datasheet URL: https://www.molex.com/pdm_docs/sd/022232031_sd.pdf - Role Details: External interface header: +5V input, GND, and filtered analog output. - Role: Switching - Manufacturer Name: Molex - Part Type: Connector - Manufacturer Part Number: 0022232031 - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### SW1 — [1825360-3](https://www.flux.ai/adrian95/1825360-3~qvc.md) - Part Type: Switch - Manufacturer Part Number: 1825360-3 - Package or Case Code: DIP810W60P254L1209H480Q8N - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: TE Connectivity - Datasheet URL: https://www.te.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=ADE_ADP_ADF_Datasheet&DocType=Data+Sheet&DocLang=English&DocFormat=pdf&PartCntxt=1825360-3 - Role Details: Selects one or more feedback resistors in parallel to adjust transimpedance gain during bench testing. - Role: Switching **Pins:** - COM_1 [pin 1] - COM_2 [pin 2] - COM_3 [pin 3] - COM_4 [pin 4] - NO_1 [pin 5] - NO_2 [pin 6] - NO_3 [pin 7] - NO_4 [pin 8] ### U1 — [OPA381AIDGKR](https://www.flux.ai/lcsc/opa381aidgkr~79a0.md) - Role Details: OPA381AIDGKR transimpedance amplifier; converts SFH 203 photocurrent into an analog voltage with selectable feedback resistance. - JLCPCB Part Class: Extended Part - Role: Amplification - LCSC Part Number: C2870973 - Part Type: Special Purpose Amplifiers - Manufacturer Part Number: OPA381AIDGKR - Mouser Part Number: 595-OPA381AIDGKR - Manufacturer Name: TI(德州仪器) - Package or Case Code: VSSOP-8_L3.0-W3.0-P0.65-LS4.9-BL **Pins:** - IN- [pin 2] - IN+ [pin 3] - NC [pin 8] - NC [pin 5] - NC [pin 1] - OUT [pin 6] - V- [pin 4] - V+ [pin 7] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/lmaples97/visible-light-sensor-tia~b6](https://www.flux.ai/lmaples97/visible-light-sensor-tia~b6).* --- *Generated from [https://www.flux.ai/lmaples97/visible-light-sensor-tia~b6](https://www.flux.ai/lmaples97/visible-light-sensor-tia~b6)*