
Description :
The MCU-2516 (CJMCU-2516) is a compact breakout module featuring the Winbond W25Q16 Non-Volatile SPI Flash Memory chip.
It is widely used with microcontrollers (Arduino, STM32, ESP8244/ESP32, Raspberry Pi) to add external storage for configuration data, audio files, images, or data logging.
Key Specifications
Capacity: 16 Megabits / 2 Megabytes (2 MB)
Interface: Standard, Dual, and Quad SPI (Serial Peripheral Interface)
Operating Voltage: 2.7V to 3.6V (typically powered via 3.3V)
Clock Frequency: Up to 104 MHz
Erase/Program Sectors: 4 KB sectors, 32/64 KB blocks
Pinout Description
VCC: Power supply (2.7V – 3.6V)
GND: Ground
CS (or CE): Chip Select / Chip Enable (Active Low)
CLK (SCK): Serial Clock input
DI (MOSI): Serial Data Input (Master Out Slave In)
DO (MISO): Serial Data Output (Master In Slave Out)
WP: Write Protect (Active Low — connect to VCC if unused)
HOLD: Hold / Pause communication (Active Low — connect to VCC if unused)
Usage Note
Since the W25Q16 chip operates strictly at 3.3V logic levels, direct connection to 5V microcontrollers (like standard Arduino Uno boards) requires a 3.3V voltage regulator for power and logic level shifters on the SPI signals to prevent damaging the chip.