The Redmi Note 5 Pro (MEI7S) Charging Board, also known as the Sub-PCB or "CC Board," is the hub for power input, data connectivity, and primary voice communication. For this model, the board is particularly important as it bridges the gap between the charging port and the high-capacity 4,000mAh battery while also housing the analog components for calls.
Below is the detailed technical description and specification breakdown in a tabular format.
| Feature | Detailed Specification |
| Compatible Model | Redmi Note 5 Pro (India) / Redmi Note 5 AI Dual Camera (Global) |
| Model Code | MEI7S, MEI7 |
| Component Type | Sub-PCB / USB Charging Port Dock Flex |
| Port Type | Micro-USB 2.0 (Standard 5-pin) |
| Fast Charge Support | Qualcomm Quick Charge 2.0 (Supports up to 18W) |
| Integrated Hardware | Micro-USB Port, Analog Microphone, Antenna Terminal, Audio Jack Path |
| Main Functions | Charging, Data Sync, Primary Microphone Input, Network Signal Reception |
| Build Quality | OEM High-Quality / Full IC Grade |
| Mounting Style | Snap-on Board-to-Board (BTB) Connector |
1. Charging & Power Delivery
Unlike budget boards, the premium Redmi Note 5 Pro board includes a dedicated Charging IC and NTC (Negative Temperature Coefficient) thermistor. This allows the device to safely negotiate 18W fast charging without overheating the sub-board or the battery.
2. Analog Microphone
The primary microphone is soldered to the bottom-left of the board. It is specifically calibrated to reduce ambient noise via the device's secondary noise-canceling mic on the top frame. Replacement is necessary if callers report "hissing" or "no sound."
3. Signal Reception (Antenna Terminal)
The gold-plated circular terminal connects to the white/black coaxial antenna cable. A "Full IC" board is required to maintain strong 4G VoLTE signal bars. Cheaper boards without these ICs often lead to "Emergency Calls Only" or frequent signal drops.


