Si858x Integrated isolation RS-485 transceiver

The Skyworks Solutions SI8585x-KIT evaluation suite provides a demonstration and development platform for the Si858x integrated isolated RS-485 transceiver. These devices combine powerful, fully compatible RS-485 transceivers with signal isolation. The Si858x transceiver is an ideal choice for industrial automation applications, requiring a fieldbus system with isolated interfaces to form a communication network connecting sensors, actuators, and controllers.

The SI8585x-KIT evaluation kit preloads the Si858x RS-485 transceiver device in a SOIC-16 WB (wide body) package for each function. Power connectors and RS-485 bus connectors are also available. Test points allow access to all critical signals. The onboard controller interface can be connected to a microcontroller board (not included). Since the Si858x device is an isolated RS-485 transceiver, two isolated voltage power supplies are required to power the SI8585x-KIT.

The VDD1 accepts a voltage level of 3.0V to 5.5V. VDD2 should be 3.3V or 5.0V, depending on the target device. The SI8585x-KIT has no special power-on sequence. The current consumption of VDD1 and VDD2 should be less than 100mA. The SI8585x-KIT has input voltage polarity protection. If a reverse polarity voltage is applied to VDD1 or VDD2, isolate it from the Si858x power supply pin to avoid damage. The onboard LED indicates a voltage supply with the correct polarity.

Features

● Pre-installed Si858x Isolation RS-485 transceiver
● Comply with TIA/EIA-485-A (RS-485) and EN 50170 (ProfiBus)
● 5kVrms Security level isolation
● Up to 10Mbps data rate
● RS-485 bus signal conversion rate control (on 1Mbps data rate devices)
● Optional 120Ω AC terminal onboard
● Common-mode transient immunity (CMTI) of 100kV/µs
● 64/256 Unit Load (UL) Supported
● Half/full duplex communication
● Flexible isolation power supply
● Reverse polarity protection of input power supply