• Decorative lantern replica installed inside a 3D-printed diffuser/housing.
• Prototype / hobby build for a student or beginner.
• Intended to run from a single-cell LiPo or protected 18650 battery and recharge from USB-C.

• Provide warm-white internal illumination through diffusers.
• Turn fully on/off with a physical switch.
• Recharge the single-cell battery from USB-C.
• Fit inside a 60 mm cubic enclosure with mounting holes.
• Be straightforward to hand solder and inspect.

• 6 warm-white LEDs arranged around the board for even glow.
• Individual LED current-limiting resistors.
• USB-C 5 V input with single-cell Li-ion/LiPo charger.
• JST battery connector for a protected 1S LiPo/18650 pack.
• Main on/off slide or rocker switch.
• Mounting holes for standoffs.
• Clear silkscreen labels for USB, battery polarity, switch, LED polarity, and mounting orientation.

Diagram

• USB-C connector provides 5 V input using standard CC pull-down resistors.
• A single-cell Li-ion/LiPo charger IC charges the battery at a conservative current suitable for small packs.
• Battery connects through a JST-style 2-pin connector.
• The first version uses a protected battery pack or protected 18650 cell; the board does not provide cell-protection cutoff by itself unless a protected battery is used.

• 6 warm-white LEDs are driven directly from the switched battery rail through one resistor per LED.
• Target LED current: about 2–5 mA each for low heat and long runtime.
• LED resistor value target: around 220–470 Ω depending on selected LED forward voltage and desired brightness.

• One physical on/off switch disconnects LED load from the battery rail.
• No MCU, no 555 timer, and no debounce circuit in v1; debounce is unnecessary for a direct power switch.

• Board max: 60 mm × 60 mm.
• Target board: 2-layer PCB for easy routing and ground pour.
• Mounting holes near corners, kept clear of enclosure walls and copper where needed.

• USB-C receptacle: 5 V charging input only, no data.
• Battery connector: 2-pin JST-compatible connector, BAT+ and BAT-.
• Switch: switched battery positive to LED rail.
• LEDs: local series resistors connected from switched rail to LED strings/individual LEDs.

• Power source: 1S LiPo / protected 18650, nominal 3.7 V, 4.2 V full, about 3.0 V depleted.
• USB-C input: 5 V charging only.
• Expected active load with 6 LEDs at ~3 mA each: ~18 mA LED current.
• Runtime example: 500 mAh cell / 18 mA ≈ 27 h ideal; practical runtime lower due to LED voltage/current variation and chosen brightness.

Diagram

• Beginner-friendly: prefer larger SMD footprints where possible (0805 passives, hand-solderable connectors/switches) or through-hole LEDs if selected.
• 2-layer PCB.
• Gerbers, BOM, and pick-and-place should be generated after DRC is clean.
• LCSC/DigiKey links should be verified before final manufacturing export.

• No firmware for v1.
• Optional future revision could add an ATTiny or 555 timer for soft fade/flicker.

• Max 60 mm × 60 mm board.
• LEDs distributed around the perimeter or symmetric pattern for even diffuser illumination.
• USB-C and switch placed where the enclosure exposes them.
• Battery connector accessible for assembly.
• Mounting holes near corners with silkscreen labels.

• Use a minimal direct LED-drive architecture instead of MCU or 555 timer for first revision.
• Use individual LED resistors instead of shared resistors for brightness consistency and robustness.
• Use USB-C charging for convenience but keep the LED circuit battery-powered and simple.
• Assume the battery includes protection unless a dedicated protection IC is later requested.

• User wants the simplest reliable first version, not soft fade/flicker.
• 6 LEDs is a good midpoint between the requested 4–8 LEDs.
• Warm-white LEDs are low-current decorative indicators, not high-power lighting LEDs.
• Enclosure access openings for USB-C and switch are not yet fixed, so final placement may need mechanical adjustment.

• Initial specification created from pasted requirements on 2026-07-22.