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

4 EVM Setup and Operation

This section describes the typical setup and operation of the EVM for device evaluation. Figure 4-1 shows a typical test configuration for operating the ISOUSB211DPEVM using an USB 2.0 type-B receptacle.

Figure 4-1 ISOUSB211 Test Setup

Use a jumper to connect pin 2 to pin 1 of J15 to enable the U3 LDO. The U3 LDO provides a 5-V supply to the USB device, and it also powers the U6 and U7 LDOs to generate 3.3 V and 1.8 V for the ISOUSB211. If an external 5-V source is used to power the USB device through TP5, connect pin 2 to pin 3 of J15 to disable the U3 LDO and set its output to high impedance.

ISOUSB211DPEVM has many DNP resistors which can be populated or unpopulated to setup the EVM to the desired operating test conditions. Table 4-1 lists and describes all the possible test configurations that can be achieved by populating various resistors.

Table 4-1 Resistor Configurations
Resistor Description
R11 DNP by default. To disable the U4 LDO, populate a 0-Ω resistor on R11 and unpopulate R12.
R12 Connects U4 EN to ground to enable the LDO. When R12 is populated, unpopulate R11.
R13 Connects VBUS1 to the type-B receptacle VBUS. VBUS1 is powered at 5 V when R13 is populated. Unpopulate R14 and R15 to disconnect the U4 LDO from the VBUS1 and V3P3V1 pins. The internal LDO of ISOUSB211 generates 3.3 V for the V3P3V1 pin.
R14, R15 DNP by default. Populating R14 and R15 connects the U4 LDO to the VBUS1 and V3P3V1 pins. When these two resistors are populated, unpopulate R13. When R14 and R15 are populated, VBUS1 and V3P3V1 are set to 3.3 V.
R16 DNP by default. To disable the U5 LDO, populate a 0-Ω resistor on R16 and unpopulate R17.
R17 Connects U5 EN to ground to enable the LDO. When R17 is populated, unpopulate R16.
R18 Connects VCC1 to the VBUS of the type-B receptacle. VCC1 is powered at 5 V when R18 is populated. Unpopulate the R19 and R20 resistors to disconnect the U5 LDO from the VCC1 and V1P8V1 pins. The internal LDO of the ISOUSB211 generates 1.8 V for the V1P8V1 pin.
R19, R20 Populating R19 and R20 connects the U5 LDO to the VCC1 and V1P8V1 pins. When these two resistors are populated, unpopulate R18. When R19 and R20 are populated, VCC1 and V1P8V1 are set to 1.8 V.
R21 DNP by default. To disable the U6 LDO, populate a 0-Ω resistor on R21 and unpopulate R22.
R22 Connects U6 EN to ground to enable the LDO. When R22 is populated, unpopulate R21.
R23 DNP by default. The R23 resistor connects VBUS2 to the output of U3 LDO. VBUS2 is powered at 5 V when R23 is populated. Unpopulate the R24 and R25 resistors to disconnect the U3 LDO from the VBUS2 and V3P3V2 pins. The internal LDO of ISOUSB211 generates 3.3 V for the V3P3V2 pin.
R24, R25 Populating R24 and R25 connects the U6 LDO to the VBUS2 and V3P3V2 pins. When these two resistors are populated, unpopulate R23 . When R24 and R25 are populated, VBUS2 and V3P3V2 are set to 3.3 V by the U6 LDO.
R26 DNP by default. To disable the U7 LDO, populate a 0-Ω resistor on R26 and unpopulate R27.
R27 Connects U7 EN to ground to enable the LDO. When R27 is populated, unpopulate R26.
R29 DNP by default. The R29 resistor connects VBUS2 to the output of U7 LDO. VCC2 is powered at 5 V when R29 is populated. Unpopulate R28 and R30 to disconnect the U7 LDO from the VCC2 and V1P8V2 pins. The internal LDO of ISOUSB211 generates 1.8 V for the V1P8V2 pin.
R28, R30 Populating R28 and R30 connects the U7 LDO to the VCC2 and V1P8V2 pins. When these two resistors are populated, unpopulate R29. When R28 and R30 are populated, VCC2 and V1P8V2 are set to 1.8 V.