Product description: QwiicBus MidPoint - SparkFun COM-18000
The MidPoint is a component of the QwiicBus system that allows you to extend the range of the I2C communication bus. Designed by Sparkfun, it usesNXP PCA9615chip, which converts two default I2C signals (SDA data line and SCL clock line)to four differential signals: two for SCL and two for SDA. For signal transmission an Ethernet cable is used, which is connected to QwiicBus MidPoint via RJ-45 sockets embedded on the board. In combination withQwiicBus EndPointit allows to transmit data at distance of about 30 meters. TheEthernet cableis not included.
Presentation of QwiicBus system components.
Communication in QwiicBus
QwiicBus keeps the I2C protocol when transferring data (does not require changing to RS-485 or 1-Wire), using differential transfer. It allows convenient connection of other QwiicBus components (such asEndPoint) via Ethernet cable. QwiicBus Midpoint has a built-in LMR33630 buck regulator that allows connection of devices with higher current requirements, up to 3 A / 3.3 V.
Apart from two Qwiic connectors and two RJ-45 sockets, board has I2C bus pins with 2,54 mm spacing for soldering:
- 3V3- power supply
- GND- ground
- SDA- data line
- SCL- clock line
Details about board architecture and its pins can be found inuser manualprepared by manufacturer.
Application of QwiicBus system
- Creating networks of sensors within home automation
- Extension of the range of projects based on I2C communication
- Due to high resistance to interference, it can be used near their sources, e.g. motors
QwiicBus MidPoint specification
- I2C supply voltage: from 2.3 V to 5.5 V
- Differential supply voltage range: 3.5 V to 5.5 V
- Buck regulator LMR33630 supply voltage range : from 3.6 V to 36 V
- Embedded IC type: PCA9615
- Pin pattern for self-soldering: 2.54 mm
- Maximum transmission distance using QwiicBus: up to 30 m