Synaptics SYN20708 low-power IoT SoC features Bluetooth, Zigbee, Thread, Matter, and advanced coexistence

Synaptics has recently introduced the SYN20708 low-power IoT SoC designed to handle simultaneous Bluetooth 5.4 Classic/Low Energy and IEEE 802.15.4 radios with Zigbee, Thread, and Matter protocols. The SoC integrates power and low-noise amplifiers and two separate radios enable simultaneous multiprotocol operations.

The SoC is based on a 160 MHz Arm Cortex-M4 processor with user-accessible OTP memory for configuration. Built using a 16-nm FinFET process, it has very low power consumption, and advanced features like high-accuracy distance measurement (HADM), angle-of-arrival (AoA), and angle-of-departure (AoD). These features with versatile antenna support make this SoC suitable for industrial, consumer, and IoT applications.

Synaptics SYN20708 specifications

CPU – Arm Cortex-M4 processor @ 160 MHz
Memory/Storage
- 544 KB System RAM
- 1664 KB Code RAM
- 1640 KB ROM
- 256 bytes OTP
Connectivity
- Dual-radio Bluetooth 5.4
  - Bluetooth Classic, Bluetooth Low Energy
  - Supports Bluetooth 6.0 features like HADM (high accuracy distance measurement)
  - Bluetooth Class 1 and Class 2 TX operation
  - BLE-LR, angle of departure (AoD), angle of arrival (AoA), and ISOC hardware support.
- IEEE 802.15.4 – Zigbee, Thread, and Matter support
RF Features
- Dual 2.4 GHz radios, concurrent operation
- Integrated 2.4 GHz PAs and LNAs
- Support for external PAs
- Integrated TR switch, support for external switch
- 4 GPIO and antenna-selection pins for AoA/AoD/HADM
Interfaces
- Synaptics-proprietary Serial Enhanced Coexistence Interface (SECI) for Wi-Fi and BT coexistence
- 3-wire IEEE 802.15.2 coexistence interface
- Optional SPI for local flash connection
- I²C master for controlling external sensors
Serial
- High-speed UART up to 12 Mbps
- Peripheral/Debug UART
Misc – Electronic Shelf Label (ESL) support
Power
- 3.3V, 1.8V, and 1.05V external supplies
- Integrated PMU and LDO regulators
Package – 103-pin FCBGA package with 0.4 mm pitch
Dimensions – 5.5 x 5.5 mm.
Operating Temperature – -40°C to +85°C (industrial range)
Process – 16 nm FinFET

The company mentions that coexistence interfaces like the Serial Enhanced Coexistence Interface (SECI) enable radios to communicate in real time, sharing transmission priorities to prevent overlaps. For example, Bluetooth can signal Zigbee to delay its activity, prioritizing critical tasks like audio streaming. Precise timing ensures tight synchronization of the radios, allocating microsecond-level time slots to avoid interference. Bluetooth’s Adaptive Frequency Hopping (AFH) further reduces congestion by dynamically switching to less crowded channels. This combination ensures reliable and efficient multiprotocol communication in dense IoT environments. Additionally, timing protocols such as adaptive frequency hopping (AFH) in Bluetooth help avoid occupied channels by dynamically steering transmissions to clearer frequencies.

At first glance, this SoC looks like a cost-down version of the SYN4383 “Triple Combo 3” Wi-Fi 6E, Bluetooth 5.4, 802.15.4 SoC because the SYN4383 features Wi-Fi 6E, whereas the SYN20708 only has Bluetooth support. The company mentions that the SYN20708 low-power IoT SoC is available now, but there is no price tag on it, and you have to contact sales through their forum for details. More information about the product can be found on the company’s products page which includes a datasheet, and the press release.

Debashis Das

Debashis Das is a technical content writer and embedded engineer with over five years of experience in the industry. With expertise in Embedded C, PCB Design, and SEO optimization, he effectively blends difficult technical topics with clear communication