PineBuds Pro

The PineBuds Pro

The PineBuds Pro are open firmware capable ANC wireless earbuds. Some of the notable features include their light weight, 3 Microphones, ANC (Active Noise Cancellation), ENC (Environment Noise Cancellation) and high fidelity 6mm speaker. It is a fully community-driven side-project which anyone can contribute to, allowing you to keep control of your device even though hardware is proprietary.

Software

Firmwares

• OpenPineBuds
• Little Buddy

Firmware images

Flash back factory default firmware using Windows based utility:

• PineBuds Pro Windows based programmer utility user manual
• PineBuds Pro Windows based programmer utility
• PineBuds Pro factory default firmware build
• PineBuds Pro factory default OTA build

SDK release

• PineBuds Pro "Little Whale" SDK date:20221128

Introduction

General information and tips about PineBuds Pro.

Buttons/touch sensors

Buds

One capacitive touch sensor is located on the outward facing surface of each bud near the logo.

Charging case

When the buds are shipped they may have stickers covering their contacts, preventing contact with the charging case. These need to be removed before the buds can be used.

The charging case has a reset button in the center under the lid (between the seats for the two buds,) which is hooked to the ThinkPlus Semi SY8821 integrated circuit and that button resets it from the safety off mode.

Cleaning

PineBuds Pro only have IPX4 rating, so they are only splash-proof and cannot withstand immersion in water. Clean the charging case inside and out with a damp microfiber cloth. Inside, be careful near the pogo pins! The cloth easily sticks to them and may tear them. You can use a microfiber cloth at the end of a stick to immerse of the buds, but a cleaning tool made for this can help. When cleaning the buds, carefully remove the tips, place the buds on a damp microfibre cloth and one by one wipe it from all sides. Be careful with the protective mesh. If there is dirt in the mesh, you can carefully clean it with the brush of the previously mentioned tool. Wash the tips with soap and water, but be careful, they easily drip from your hand to drain. After drying them, carefully put them back to the buds.

You need:

• A microfiber cloth
• A cleaning tool like this or this

Community projects

The following community projects are currently being worked on:

• Wireless charging, bringing wireless charging to the PineBuds Pro case using vacant contacts
• Silicone case, a transparent silicone case with an improved grip to the case
• Straps, to add straps to the PineBuds Pro

Disassembly / Assembly

Disassembling the charging case:

Note: A video tutorial regarding the disassembly can be watched from Linux Lounge here

1. First open the lid and then try to press the case from the front edge with a plectrum or a thin card. There are two clips on each side. Soon the case will snap open.
2. Carefully unscrew and remove the PCB from the case.

Assembling the charging case:

Note: A video tutorial regarding the assembly can be watched from Linux Lounge here (at the 3:50 minutes timestamp)

1. Screw the PCB back into the place.
2. There is plenty of space, glue the coil to the bottom of the case.
3. Close the charging case.

Specifications

Dimensions:

• Earbud: Unknown
• Charging case: 70 x 50 x 35mm (unconfirmed)

Weight:

• Earbud: 5g
• Charging case: 65g

IP Rating of Earbuds: IPX4

Dynamic transducer (speaker): 6mm

Microphone: 3 – FeedForward, FeedBack, Talk

System on Chip (in each earbud): BES 2300YP

• CPU: Dual-core 300MHz ARM Cortex-M4F
• ROM: 448KB
• SRAM: 992KB
• BT shared SRAM: 64KB
• Flash: 4MB (Endurance erase cycles: >500)

Communication:

• Bluetooth: Bluetooth 5.2 dual-mode compliant
• USB: USB to dual UARTs at charging case

Battery:

• Earbud: Built-in LiPo 3.7V 40mAh
• Charging case: Built-in LiPo 3.7V 800mAh

Ports earbud:

• 4 pins

Ports charging case:

• 4 pogo pins
• USB type-C port 5V 500mA

SoC and Memory Specification

The PineBuds Pro's buds are based on the BES 2300YP.

BES2300YP block diagram

CPU Features:

• Dual-core ARM Cortex-M4F Processor Processor up to 300MHz CPU
• CMOS Single-chip Fully-integrated RF, PMU, Audio CODEC and Cortex-M4F CPU

Memory Features:

• 4MB Serial Flash On-chip for Custom Program
• Internal ROM 448KB for critical constants and code
• Internal SRAM 992KB for critical data and code

BT Features:

• Bluetooth 5.2 dual-mode compliant
• Profiles: A2DP, AVRCP, HFP
• Audio Codecs: SBC, AAC

Audio Features:

• Support BES Intelligent Bluetooth Retransmission (IBRT)
• Support FF/Hybrid ANC
• Dual MICs noise reduction
• Echo Cancellation
• Support low power voice activity detection
• Multi-band EQ and Bass enhancement
• Support Active Crossover
• Support TWS
• HiFi Stereo Audio DAC: 120dB SNR, 110dB DNR
• HiFi Stereo Audio ADC: 100dB SNR
• Sample rates from 8 kHz to 384 kHz
• Support dual/single Mic noise suppression
  • -45dB attenuation nominal 50-200Hz
  • -55dB max attenuation @150Hz
• Support ambient awareness
• Support talk through
• 24-bit audio processing

PMU Features

• 3.1V-5.5V Input for VBAT
• Internal LPO for low power mode.
• DCXO with internal oscillator circuit
• Internal temperature sensor

Information, Schematics and Certifications

The charging case's input power: DC 5V @ 0.5A USB Type-C

Documents:

• PineBuds Pro User Manual

Schematics:

• PineBuds Pro Earbuds Schematic 20220817
• PineBuds Pro Charging Case Schematic 20220915

Certifications:

• PineBuds Pro CE EMC Certificate
• PineBuds Pro CE RED Certificate
• PineBuds Pro FCC Certificate
• PineBuds Pro ROHS Report

Datasheets for Components and Peripherals

BES 2300YP SoC information:

• BES 2300-YP Datasheet V1.0

Charging case:

• ThinkPlus Semi SY8821 Datasheet in Chinese
• WCH Tech CH342DS USB to Dual Serial ports chip Datasheet
• COPO CP2021 2.5W Qi Wire Power Receiver Datasheet (Unpopulated)

EarBuds:

• ChiPower Tech CE3156 Single Cell Charger Datasheet
• LowPower Semi LP3992 LDO Regulator Datasheet
• HLW Semi HLW-YHX190 OTP micro Datasheet in Chinese (noted: for power-on and reset control)
• Tontek TTP-233D one key touch pad detect IC Datasheet