KT6368A Bluetooth chip IC/Board Module Serial Port BLE SPP

Project Overview: KT6368A Bluetooth Chip

Project Name: KT6368A Bluetooth Dual-Mode Chip Integration

Objective: To embed low-cost, easy-to-use Bluetooth functionality into devices for bidirectional data communication (e.g., IoT sensors, wearables, industrial controls).

Why This Project?

1. Cost-Effective Solution

🔹The KT6368A offers competitive pricing and minimal development overhead, ideal for mass production.

🔹Eliminates complex Bluetooth protocol stacks, reducing R&D time.

2. Dual-Mode Flexibility

Supports both BLE (Bluetooth Low Energy) and SPP (Classic Bluetooth), catering to diverse needs:

🔹BLE for energy-efficient apps (e.g., health monitors).

🔹SPP for Android devices requiring high-throughput data (e.g., serial communication).

3. Simplified Integration

🔹Pre-programmed firmware and AT commands enable quick setup without deep Bluetooth expertise.

🔹Small SOP8 package simplifies PCB design.

How It Works

1. Hardware Setup

🔹Power Supply: 2.2V–3.3V (LDO recommended; avoid MCU GPIO power).

🔹UART Interface: Connects to an MCU via TX/RX pins (100Ω series resistors for level protection).

🔹Antenna: Simple wire antenna or PCB trace (ensure clearance; no metal interference).

🔹Crystal Oscillator: 24MHz, ±10ppm accuracy (critical for RF stability).

2. Key Functionalities

👉 AT Command Control:

🔹Set Bluetooth name (`AT+BM<name>\r\n`), baud rate (`AT+CT01\r\n` for 9600 bps), or UUID (`AT+U0FFF0\r\n`).

🔹Example: `AT+BMMyDevice\r\n` renames the BLE device to "MyDevice".

👉 Data Passthrough:

🔹BLE Mode: Data sent via UART is transmitted to a phone app (e.g., LightBlue) after enabling Notify on UUID `FFF1`.

🔹SPP Mode: Acts as a virtual serial port for Android devices.

👉 Connection Status:

🔹Pin 2 outputs high when connected (LED indicator possible).

3. Low-Power Option (KT6328A Version)

👉 Average current: 20µA (unconnected) / 4.3mA (connected).

👉 Broadcast interval adjustable (`AT+UT03\r\n` for 1000ms interval).

4. Testing & Debugging

👉 Initial Checks:

🔹Verify power-on serial output (e.g., `TM+KT6368A-BLE`).

🔹Use a Bluetooth test box to validate frequency deviation (±20KHz max).

👉 Common Pitfalls:

🔹Crystal oscillator quality affects connectivity.

🔹Incorrect AT command formatting (must end with `\r\n`).

Example Use Case

Smart Sensor Hub:

1. MCU (e.g., STM32) collects temperature data.

2. KT6368A transmits data via BLE to a phone app (UUID `FFF1`).

3. App processes data and sends commands back (e.g., `AT+BR05\r\n` to reduce transmission power).

Outcome: Real-time monitoring with minimal power consumption.

Key Takeaways

👉 Strengths: Low cost, dual-mode support, plug-and-play AT commands.

👉 Challenges: Crystal oscillator selection, timing for AT commands (wait 2.5s after power-up).

👉 Ideal For: Rapid prototyping and scalable production of Bluetooth-enabled devices.

For detailed commands, refer to Sections 3 (Serial Protocol) and 4 (BLE Passthrough) in the manual.