SBOU261 October   2021 ISOUSB211

 

  1.   Trademarks
  2. 1Introduction
  3. 2Overview
  4. 3Pin Configuration of the ISOUSB211 High-, Full-, and Low-Speed Isolated USB Repeater
  5. 4EVM Setup and Operation
  6. 5EVM Schematics
  7. 6PCB Layout and 3D Diagram
  8. 7Bill of Materials

2 Overview

The ISOUSB211 device is a galvanically-isolated USB 2.0 compliant repeater supporting low-speed (1.5 Mbps), full-speed (12 Mbps), and high-speed (480 Mbps) signaling rates. The device supports automatic connect and speed detection, reflection of pullups and pulldowns, and link power management allowing drop-in USB hub, host, peripheral and cable isolation. The device also supports automatic role reversal - if after disconnect, a new connection is detected on the upstream facing port, then the upstream and downstream port definitions are reversed. The ISOUSB211 has built-in programmable equalization to cancel signal loss caused by board traces, which helps in meeting USB 2.0 high-speed TX and RX eye-diagram templates. This device uses a silicon dioxide (SiO2) insulation barrier with a withstand voltage of 5700 VRMS and a working voltage of 1060 VRMS. Used in conjunction with isolated power supplies, the device protects against high voltage, and prevents noise currents from the bus from entering the local ground. The ISOUSB211 device is available for both basic and reinforced isolation. The ISOUSB211 device supports a wide ambient temperature range of –40°C to +115°C. The device is available in the small footprint 28-pin SSOP (DP-28) package.

The EVM enables users to evaluate the ISOUSB211 device thoroughly before incorporating the device into their designs. To facilitate the EVM to be powered from various power sources including regulated power supplies, standard USB2.0 connector, and standard DC adapter, the EVM includes a transformer driver (SN6501), a transformer (CMP-0030614-1), and five adjustable output LDOs (TPS76701 and TPS73701). This EVM can be configured to use the provided LDOs to power the 3.3-V and 1.8-V power supplies, or bypass these external LDOs and use the internal LDOs to power the 3.3-V and 1.8-V power supplies. The EVM can be configured to operate with and without external LDOs and test configurations details of which are provided in the following sections.

The EVM can be used to verify many of the ISOUSB211 data sheet parameters like data-rate, current consumption, and others. Some of the data sheet specifications require a different test setup configuration than the ISOUSB211DPEVM and hence, they cannot be verified from the EVM as is. The example parameters include maximum data rate, propagation delay, and other timing specifications.