# Solar MP3 Player ## Description Batteryless 5 V solar-powered MP3 player for the Voltaic P123 panel, with automatic loop playback, UVLO hysteresis, reservoir energy buffering, microSD storage, and a small speaker output. ## Project Details - **Owner:** ttabb - **Created:** 8/6/2026 - **Last Updated:** 8/6/2026 - **Visibility:** Public ## Key Components ### D1 — [PMEG2005EJ](https://www.flux.ai/kicad-part-library/pmeg2005ej~lj.md) - Datasheet URL: https://assets.nexperia.com/documents/data-sheet/PMEGXX05EH_EJ_SER.pdf - Part Type: Diode SMD - Manufacturer Part Number: PMEG2005EJ - Functional Group: Solar Input and Protection - Manufacturer Name: Texas Instruments Inc. - Package or Case Code: D_SOD-323F - Role Details: Prevents reservoir discharge into shaded panel - Role: Protection **Pins:** - A [pin 2] - K [pin 1] ### D2 — [ESD5341N](https://www.flux.ai/lcsc/esd5341n~k8iz.md) - Functional Group: Solar Input and Protection - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: DFN1006-2L-RD - JLCPCB Part Class: Extended Part - Forward Voltage: 0.7V at 1AV - Role: Protection - Part Type: TVS - Manufacturer Part Number: ESD5341N - Datasheet URL: https://www.lcsc.com/datasheet/C3021106.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNeR1VbVVxRR1JXUTsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D - Role Details: Solar connector ESD transient clamp - Diode Type: TVS Diode - Max Reverse Voltage: 5V - Manufacturer Name: TECH PUBLIC(台舟) - LCSC Part Number: C3021106 **Pins:** - 1 [pin 1] - 2 [pin 2] ### J1 — [1.25-2P](https://www.flux.ai/lcsc/1p25-2p~h7og.md) - Functional Group: Solar Input and Protection - Role Details: 5 V nominal, 0.6 W panel - Package or Case Code: CONN-SMD_1.25-2P - Manufacturer Name: SHOU HAN(首韩) - LCSC Part Number: C393945 - Product Info Url: https://lcsc.com/product-detail/Wire-To-Board-Wire-To-Wire-Connector_SHOU-HAN-1-25-2P_C393945.html - JLCPCB Part Class: Extended Part - Role: Solar input - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/1912111437_SHOU-HAN-1-25-2P_C393945.pdf - Manufacturer Part Number: 1.25-2P - Part Type: Wire To Board / Wire To Wire Connector **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] ### J2 — [1.25-2P](https://www.flux.ai/lcsc/1p25-2p~h7og.md) - LCSC Part Number: C393945 - Functional Group: Speaker Output - Manufacturer Name: SHOU HAN(首韩) - Package or Case Code: CONN-SMD_1.25-2P - JLCPCB Part Class: Extended Part - Product Info Url: https://lcsc.com/product-detail/Wire-To-Board-Wire-To-Wire-Connector_SHOU-HAN-1-25-2P_C393945.html - Role Details: BTL output; neither pin grounded - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/1912111437_SHOU-HAN-1-25-2P_C393945.pdf - Manufacturer Part Number: 1.25-2P - Part Type: Wire To Board / Wire To Wire Connector - Role: Speaker output **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] ### U1 — [DFR0299](https://www.flux.ai/adrian95/dfr0299~dmv.md) - Role: MP3 playback module - Part Type: Development Board - Role Details: DFRobot documents 3.2-5 V operation and IO1/IO2 as momentary previous/next or long-press volume keys; automatic power-on loop is not authoritative and needs validation or controller circuitry - Functional Group: MP3 Storage and Audio - Manufacturer Part Number: DFR0299 - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://raw.githubusercontent.com/Arduinolibrary/DFPlayer_Mini_mp3/master/DFPlayer%20Mini%20Manual.pdf - Manufacturer Name: DFRobot **Pins:** - ADKEY1 [pin 12] - ADKEY2 [pin 13] - BUSY [pin 16] - DAC_L [pin 5] - DAC_R [pin 4] - GND [pin 7] - GND [pin 10] - IO1 [pin 9] - IO2 [pin 11] - RX [pin 2] - SPK1 [pin 6] - SPK2 [pin 8] - TX [pin 3] - USB- [pin 15] - USB+ [pin 14] - VCC [pin 1] ### U2 — [TLV3012AIDCKR](https://www.flux.ai/lcsc/tlv3012aidckr~i8px.md) - Package or Case Code: SC-70-6_L2.0-W1.3-P0.65-LS2.1-BR - Manufacturer Part Number: TLV3012AIDCKR - Part Type: Comparators - Manufacturer Name: TI(德州仪器) - Role Details: Controls 120 mA-class solar load; ON about 4.6 V, OFF about 3.8 V - Role: Undervoltage lockout - LCSC Part Number: C2860248 - JLCPCB Part Class: Extended Part - Functional Group: UVLO and Power Switch **Pins:** - IN- [pin 4] - IN+ [pin 3] - OUT [pin 1] - REF [pin 5] - V- [pin 2] - V+ [pin 6] ### U3 — [SiP32431DR3](https://www.flux.ai/kicad-part-library/sip32431dr3~n1y.md) - Datasheet URL: http://www.vishay.com.hk/docs/66597/sip32431.pdf - Manufacturer Part Number: SiP32431DR3 - Role Details: Reverse-blocking switched feed sized above 150 mA transient - Functional Group: UVLO and Power Switch - Role: Load switch - Package or Case Code: SOT-363_SC-70-6 **Pins:** - GND [pin 5] - GND [pin 2] - IN [pin 4] - NC [pin 6] - ON [pin 3] - OUT [pin 1] ### U4 — [CB](https://www.flux.ai/lcsc/cb~gve.md) - Product Info Url: https://lcsc.com/product-detail/Low-Dropout-Regulators-LDO_MICROCHIP_MCP1702T-5002E-CB_MCP1702T-5002E-CB_C180192.html - JLCPCB Part Class: Extended Part - Role Details: P123 rated 0.10 A at 5.89 V expected MPP; 5.0 V/250 mA LDO, 2 uA typical IQ, 13.2 V input rating protects against 7.25 V Voc - Role: Power Conversion - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2410121940_Microchip-Tech-MCP1702T-5002E-CB_C180192.pdf - LCSC Part Number: C180192 - Manufacturer Name: MICROCHIP(美国微芯) - Functional Group: Solar Input and Protection - Package or Case Code: SOT-23_L2.9-W1.3-P1.90-LS2.4-BR - Part Type: Linear Voltage Regulators (LDO) - Manufacturer Part Number: MCP1702T-5002E/CB **Pins:** - GND [pin 1] - VIN [pin 3] - VOUT [pin 2] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/ttabb/solar-mp3-player~an](https://www.flux.ai/ttabb/solar-mp3-player~an).* --- *Generated from [https://www.flux.ai/ttabb/solar-mp3-player~an](https://www.flux.ai/ttabb/solar-mp3-player~an)*