DFPlayer Mini MP3 module pinout

DFRobot DFR0299 reads audio from a microSD card and supports both serial commands and simple button control.

DFR0299 module

16 contacts Current package

DFRobot · 20 × 20 mm · two rows of eight contacts

DFR0299 module pinout

Top view. Identify the VCC end and match the board markings before wiring.

Selected pin details

9 · IO1

Input · Inputs

Ground momentarily for the previous track. A long press reduces volume in I/O mode.

DFRobot DFR0299 documentation, Pinout and Work Mode

Electrical limits · Link to this pin

All 16 pins

Pin	Signal	Direction	Function
1	VCC Supply input	Supply input	Use a regulated 3.2–5 V supply. The speaker stage can draw more current while playing.
2	RX Input	Input	UART command input. DFRobot shows a series 1 kΩ resistor in the example.
3	TX Output	Output	UART response output. Use a receiver compatible with the module’s logic levels.
4	DAC_R Analog output	Analog output	Right audio DAC output for an external audio input.
5	DAC_L Analog output	Analog output	Left audio DAC output for an external audio input.
6	SPK1 Bridge output	Bridge output	One side of the amplified speaker output. Connect the speaker between SPK1 and SPK2.
7	GND Return	Return	Module ground. Share this reference with the UART controller.
8	SPK2 Bridge output	Bridge output	Other side of the amplified speaker output. Keep both speaker leads isolated from ground.
9	IO1 Input	Input	Ground momentarily for the previous track. A long press reduces volume in I/O mode.
10	GND Return	Return	Module ground.
11	IO2 Input	Input	Ground momentarily for the next track. A long press increases volume in I/O mode.
12	ADKEY1 Analog input	Analog input	First resistor-coded key input. Use the key resistance table for this module.
13	ADKEY2 Analog input	Analog input	Second resistor-coded key input. Use the key resistance table for this module.
14	USB+ USB data	USB data	Positive USB data contact for the supported storage interface.
15	USB− USB data	USB data	Negative USB data contact for the supported storage interface.
16	BUSY Output	Output	Playback status output. Low indicates playback in progress.

Signal assignments

9600 bit/s UART

Cross RX and TX and share ground. The DFRobot example uses 8 data bits, no parity and one stop bit.

Speaker output

The speaker is connected across the two amplifier outputs. Use the DAC pins for single-ended line-level signals.

Electrical limits

Parameter	Limit	Conditions and source
Supply voltage3.2–5 V	3.2–5 V	The example uses 5 V. Allow headroom for playback current. DFRobot DFR0299 documentation, Pinout and Work Mode
StorageFAT16 or FAT32 · up to 32 GB	FAT16 or FAT32 · up to 32 GB	Insert or remove the card with power off. DFRobot DFR0299 documentation, Pinout and Work Mode
Serial mode9600 bit/s · 8N1	9600 bit/s · 8N1	Use a 3.3 V logic UART and shared ground in the example. DFRobot Arduino example

Models and documents

This guide follows the DFRobot DFR0299 module’s 16-contact pinout. Check the seller’s documentation for lookalike modules and different audio chips.

DFR0299: DFRobot DFPlayer Mini module.

DFRobot DFR0299 documentation· Module pinout, specifications, serial and switch wiring.
DFRobot Arduino example· UART framing and playback initialization.