Shenzhen Jingfeihong Technology Co., Ltd.
1st Floor, Factory Building No.6, Hekan Village, BanTian Street, Longgang District, Shenzhen, Guangdong, China
Cao Yangfu
+86 15601649610
Chip-level simplicity: A single SOT23-5 linear charging IC (TP4056/AH4056H) completes 5 V→4.2 V/1 A CC/CV charging. Only 2 chip capacitors and 1 PROG resistor required externally; BOM cost ≤ 0.5 CNY. High-voltage upgrade: AH4056H supports 28 V input, with built‑in 6.25 V OVP, battery reverse‑current protection, and 150 ℃ thermal shutdown. Safe for hot‑plugging 12 V car chargers without damage. 4-stage smart charging: Trickle → Constant Current → Constant Voltage → Auto Stop. Recharge threshold at 4.05 V. Standby battery leakage ≤ 1 µA, no power loss during long‑term storage. Status indication: CHRG (red) / DONE (green) open‑drain dual LED. Flashes at 1 Hz when no battery connected for quick fault detection. Ultra-small package: ESOP8 / DFN2×2-8 available, board area only 6 mm². Fits TWS earbud cases, lipstick power banks, smart wearables and other compact spaces. Integrated protection board: Onboard 8205A + DW01 provides 4.3 V overcharge, 2.4 V over‑discharge, 3 A over‑current, and 0 V short‑circuit protection. Ready for Amazon, AliExpress sales. Plug‑and‑play: USB‑A female + 18650 nickel pad. Input 5 V/1 A, output 5 V/1 A. Dimensions 18 × 28 mm. 100 prototypes in 7 days. Ideal low‑cost solution for DIY, gifts and promotions.
# I. Market & Applications Capacity: 1×18650 (2000–3500 mAh) or 1×polymer (2500–5000 mAh). Finished size similar to lipstick, weight ~50 g. Ideal for TWS earbud cases, mini flashlights, smart wearables, and promotional gifts. Power: 5 V/1 A output, 5 V/1–2 A input. Mature, cost-effective solution with monthly shipments in tens of millions. # II. Chip Solution Comparison | Model | Package | Max Charge Current | Input Voltage | Battery Leakage (Standby) | Features | Price (CNY) | |----------|-------------|--------------------|---------------|---------------------------|-------------------------------------------|-------------| | TP4056 | SOT23-5 | 1 A | 6.5 V | 2 µA | Most popular, abundant resources | 0.18 | | AH4056H | ESOP8 | 1.2 A | 28 V | 1 µA | 12 V car charger hot-plug safe | 0.25 | | FS4057 | ThinSOT-23 | 0.5 A | 6 V | 1 µA | Ultra-small for 0.5 A applications | 0.20 | | PW4056 | SOP8-EP | 1 A | 6 V | 2 µA | Dual LED indication | 0.22 | Conclusion: TP4056 is the lowest-cost choice for 5 V/1 A USB‑A output. Choose AH4056H for 12 V car charger compatibility. FS4057 for extreme space constraints. # III. Hardware Architecture (TP4056 Example) ## Linear CC/CV Charging Input 5 V, internal PMOS regulator outputs 4.2 V±1 %. Max 1 A, programmable via external RPROG: I = 1200 / RPROG (kΩ → mA). No external MOS, Schottky, or sense resistor. BOM only 3 capacitors + 1 resistor + 2 LEDs, cost < 0.5 CNY. ## 4‑Stage Charging Curve Trickle (<3 V) → Constant Current (1 A) → Constant Voltage (4.2 V) → Auto Stop (C/10 ≈ 100 mA). Battery leakage ≤ 2 µA after full charge, no self-drain during long‑term storage. ## Status Indication CHRG (red, open‑drain): on during charging, off when full. STDBY (green): on when full, 1 Hz flashing without battery. ## Thermal Feedback Internal thermal regulation: current foldback at 120 ℃, shutdown at 150 ℃. Maintains 600 mA charging at 85 ℃ ambient to avoid plastic case deformation. ## 2‑in‑1 Protection Board Onboard 8205A + DW01 provides: - Overcharge: 4.3 V - Over‑discharge: 2.4 V - Over‑current: 3 A - Short‑circuit: 0 V Suitable for direct sale on Amazon, AliExpress. # IV. Key Performance Test (TP4056 Sample) | Item | Specification | Remarks | |-----------------------|---------------------|------------------------------------------| | Input Voltage | 4.5–6.5 V | Works with 5 V/1–2 A adapters | | Charge Voltage | 4.2 V±1 % | 4.195 V measured at 25 ℃ | | Charge Current | 0.1–1 A | 1 A at RPROG = 1.2 kΩ | | Standby Leakage | 2 µA | Battery 4.2 V, chip shutdown | | Recharge Threshold | 4.05 V | SOC ≈ 85 % | | LED Indicator Current | 2 mA | 1 kΩ current limiting | | PCB Size | 18 mm × 28 mm | Double-layer, single-sided SMT | # V. Design & Mass Production Guidelines - **Input capacitor**: 10 µF/6.3 V X5R, placed within 2 mm of VCC to suppress hot‑plug spikes. - **RPROG**: 1 % precision resistor, TCR ≤ 100 ppm, to ensure 1 A ±5 % accuracy. - **Thermal**: 0.8 W dissipation at 5 V→4.2 V/1 A. Requires ≥20 mm² copper area or 0.3 mm aluminum sheet. - **Battery protection**: DW01 + TP4056 in series provides dual protection, meets IEC62133. - **Auto power-on**: Add MX10 protocol IC for plug‑and‑play without a button. - **Certification**: For CE/FCC, add 5 V TVS + common-mode choke for 4 kV EFT / ±8 kV ESD (extra ~0.08 CNY).