MT6631N IC

Product Details
Product Details:

- Part Number: MT6631N (Marking: MT6631N)

- Manufacturer: MediaTek Inc. (MTK)

- Function: 4-in-1 Highly Integrated Wireless Connectivity SoC

- Integrated Wireless Protocols:

* Dual-Band Wi-Fi: IEEE 802.11 a/b/g/n/ac (2.4GHz & 5GHz)

* Bluetooth: Bluetooth 5.0 + BLE (Bluetooth Low Energy)

* Satellite Navigation (GNSS): GPS, GLONASS, BeiDou, Galileo

* FM Radio Receiver with digital stereo decoding

- Interface to Host SoC: SDIO (for Wi-Fi) / UART (for Bluetooth) / I2S (for Audio)

- Power Rails Required: VDD_WIFI (3.3V / 1.8V), VDD_IO (1.8V), VDD_CORE (1.1V–1.3V provided by main PMIC like MT6357)

- Package Type: Fine-Pitch QFN-40 / WLCSP BGA

- Stencil Compatibility: YCS MTK-05 / Amaoe Universal MTK Connectivity Stencil (0.12mm)

- Recommended Solder Paste: 183°C Leaded Solder Paste

Usage:

- Wireless Communication Controller: Provides short-range wireless networking, audio peripheral streaming, and satellite positioning for the application processor.

- Target Devices & Compatible Models:

* Samsung: Galaxy A10s (SM-A107F / A107M)

* Oppo / Realme: Oppo Reno 2, Oppo A1k, Oppo A5s, Oppo A12, Oppo A15, Realme C2, Realme C11, Realme C12

* Xiaomi / Redmi: Redmi 6, Redmi 6A, Redmi 9A, Redmi 9C, Redmi Note 4 (MediaTek variant), Redmi Note 8 Pro (companion connectivity)

* Huawei / Honor: Honor 9A, Honor 8A, Huawei Y6 Prime 2019

* Tecno / Infinix: Tecno Spark 5, Spark 6 Go, Infinix Hot 8, Hot 9 Play, Smart 5

- Common Fault Symptoms & Motherboard Diagnostics:

* Wi-Fi & Bluetooth Greyed Out (Samsung A10s / Redmi 6A classic fault):

- Tapping the Wi-Fi or Bluetooth slider in Settings causes it to freeze in the "Turning on..." state or immediately snap back to OFF.

- Caused by fractured solder joints beneath MT6631N after physical drops or an internally burnt logic stage.

* Weak Wi-Fi Signal / Low Range:

- Phone only detects routers when placed within 1–2 meters of the access point. Caused by a degraded internal LNA (Low-Noise Amplifier) or damaged RF front-end filtering pin.

* Standby Battery Drain & Motherboard Heating:

- Phone discharges quickly on standby and gets warm under the RF shielding can near the MT6631N, caused by leakage across the 1.8V VIO or 3.3V VDD_WIFI power rails.

* GPS Location Failure:

- Google Maps displays "Searching for GPS" continuously or shows wild drift in location tracking.

* Total Power Failure (Dead Board Short):

- A direct short across the decoupling capacitors surrounding MT6631N pulls down the 1.8V system I/O rail, preventing the main CPU and PMIC from booting.