CN3302 Type-C 2S Lithium Battery Charger Module – 8.4V Step-Up Boost Charging Board (3–6V USB-C Input)

Charge any 2S (7.4V) Li-ion or Li-Po battery pack from a standard 5V USB Type-C source with this compact step-up (boost) charging board, built around the Consonance CN3302 PFM step-up charge controller. It boosts a 3–6V USB-C input up to a regulated 8.4V using a true constant-current + Quasi-CV charge profile, with an external N+P power MOSFET, SS34 Schottky, and 10µH inductor for reliable energy transfer. Ideal for DIY power banks, 18650/21700 packs, robotics, solar projects, and portable electronics.

⚠️ 5V USB-C input ONLY. Do NOT apply 12V or anything above 6V — it will destroy the board. For a 12V source you need a buck (step-down) 2S charger, not this boost module.

Key Features

• Consonance CN3302 controller — PFM step-up charge management driving an external N+P MOSFET
• Wide USB-C input — works from 2.75V to 6.5V (board rated 3–6V); on-chip UVLO shuts down below ~2.65V
• True CC + Quasi-CV charging — constant current until 8.4V, then reduced-current Quasi-CV, then automatic termination
• Selectable charge current — set by the on-board RCS sense resistors (1A / 2A / 4A solder-jumper versions)
• Solar / weak-adapter friendly — input-power-adaptive function automatically lowers charge current to match a weaker source
• Automatic recharge — resumes charging if the pack drops below the recharge threshold while still plugged in
• Dual status LEDs — CR (charging) and OK (full / constant-voltage)

How It Charges

On power-up the CN3302 begins constant-current charging. As the pack approaches 8.4V it enters Quasi-CV mode (charge current is reduced) to compensate for voltage drop across the cells' internal resistance, then terminates cleanly. If the battery later falls below the recharge threshold, charging restarts automatically.

Protection

• Battery over-voltage protection
• Input under-voltage lockout (UVLO)
• Low-battery / short-circuit current fold-back
• IC internal over-temperature (thermal-shutdown) protection
• Note: this board has no NTC battery-temperature sensing and no cell-balancing

Technical Specifications

Applications

DIY power banks · 18650/21700 battery pack assembly · solar-charged battery systems · robotics & RC · portable audio · handheld instruments · IoT and embedded projects.

Frequently Asked Questions

Q: Can I power this with 12V?
No. It's a 3–6V USB-C boost charger. 12V will damage the CN3302 and over-volt the battery. Use a buck-type 2S charger for a 12V supply.

Q: Does it balance the two cells?
No. This is a series-pack step-up charger with no balance leads. For balanced charging, add a separate 2S BMS/balancer board.

Q: Does it protect against overheating?
The CN3302 has internal IC over-temperature shutdown. It does not monitor battery-pack temperature (no NTC input).

Q: Can I run it from a solar panel?
Yes — the CN3302 self-adapts to weaker sources by reducing charge current, which suits 5V solar input. Keep panel output within 3–6V.

Q: Can it charge a single 3.7V cell?
No. This is a 2S (8.4V) charger. Use a TP4056-type board for a single cell.

اردو میں مختصر تفصیل (Roman Urdu)

Yeh module Consonance CN3302 chip par bana step-up (boost) charger hai jo aap ke 2S (7.4V) lithium pack ko aam 5V Type-C se charge karta hai — 3–6V input ko 8.4V tak barha kar CC + Quasi-CV mode mein. Charge current board ke RCS jumpers (1A/2A/4A) se set hoti hai.

Zaroori baat: Sirf 5V USB-C ke liye. 12V ya 6V se zyada na lagayen — board jal jayega. 12V se charge karna ho to buck charger chahiye. Ye board cells ko balance nahi karta aur QC fast charge support nahi karta. Solar/kamzor adapter ke saath bhi chal jata hai. Protection: battery over-voltage, input low-voltage, short-circuit, aur chip ki garmi se bachao. NTC (battery temperature) sensing nahi hai. Do LED: CR = charging, OK = full.

Package Includes

1 × CN3302 Type-C 2S 8.4V Step-Up Charger Module