MAX33250ESHLD# Analog Devices

Click here for production status of specific part numbers. Evaluates: MAX33250E MAX33250E Shield General Description Quick Start The MAX33250E Shield is a fully assembled and Required Equipment tested PCB that demonstrates the functionality of the MAX33250E Shield MAX33250E, isolated 2Tx/2Rx RS-232 transceivers, 5V, 500mA DC power supply with a galvanic isolation of 600V (60sec) between RMS the logic UART side and field side. The isolation barrier Function generator protects the logic UART side from electrical transient Digital oscilloscope with 2 input channels strikes from the field side. It also breaks ground loops and large differences in ground potentials between the two Procedure sides that can potentially corrupt the receiving and sending The Shield EV kit is fully assembled and tested. Follow of data. The MAX33250E conforms to the EIA/TIA-232E the steps below to verify board operation: standard and operates at data rates up to 1Mbps. 1) Place the MAX33250E Shield on a nonconductive surface to ensure that nothing on the PCB gets Features shorted to the workspace. Single Supply 2) Make sure all jumpers are in their default positions On-Board Isolation Power Supply as shown in Table 1. 3) Connect T1OUT test point to R1IN test point. Arduino/Mbed Shield Interface and Form Factor 4) Connect T2OUT test point to R2IN test point. DCE/DTE Selectable DB9 Pinout 5) Disable the output of the function generator. 6) Set the output of the function generator to 500kHz (min = 0V, max = 5V) square wave. Ordering Information appears at end of data sheet. 7) Connect the positive terminal of the function genera- tor to T1IN and T2IN test points. 8) Connect the negative terminal of the function gen- erator to GNDA connector. 9) Connect the positive terminal of 5V supply to VCCA EXT connector. 10) Connect the negative terminal of 5V supply to GNDA connector. 11) Connect the positive terminal of channel 1 of the oscilloscope to R1OUT test point. 12) Connect the negative terminal of channel 1 of the oscilloscope to GNDA connector. 13) Connect the positive terminal of channel 2 of the oscilloscope to R2OUT test point. 14) Connect the negative terminal of channel 2 of the oscilloscope to GNDA connector. 15) Enable the output of the function generator. 16) Verify 500kHz 5V square waves appear on both channels of the oscilloscope. 319-100249 Rev 0 9/18Evaluates: MAX33250E MAX33250E Shield Powering the Board Detailed Description of Hardware VCCA of MAX33250E can come from external supply or MAX33250E Shield is fully assembled and tested circuit the Arduino/Mbed platform supply. See Table 1 for jumper board for evaluating the MAX33250E 1Mbps, 600V RMS settings to select appropriate VCCA source. isolated RS-232 transceivers. The MAX33250E has 2 transmitters and 2 receivers (2Tx/2Rx). The isolation is The MAX33250E Shield has an on-board isolated power provided by Maxims proprietary insulation material that can supply that generates an isolated supply for VCCB. If the withstand 600V for 60 seconds. The MAX33250E RMS shield board is connected to a Arduino/Mbed platform, conforms to the EIA/TIA-232 standard and operates at input of the isolated power supply is connected to the 5V data rates up to 1Mbps over the temperature range of output (pin 4 of J3) of the Arduino/Mbed platform. The -40C to +85C. voltage generated on the isolated output is same as the input. See Table 1 for jumper settings to select appropriate The MAX33250E Shield, with an onboard DB9 connector, VCCB source. enables Mbed or Arduino platforms to communicate on an RS-232 bus. DCE/DTE DB9 pinout is selectable with the SW1 switch. The MAX14850 digital isolator is used as a level translator with a 3V to 5.5V supply range. Table 1. Jumper Settings SHUNT JUMPER DESCRIPTION POSITION 1-2 Transceiver VCCA connects to 3.3V on Arduino/Mbed connector (J3) JU1 1-3 Transceiver VCCA connects to 5V on Arduino/Mbed connector (J3) 1-4* Transceiver VCCA connects to VCCA EXT connector 1-2* Transceiver VCCB connects to the output of the isolated power supply JU2 2-3 Transceiver VCCB connects to VCCB EXT connector 1-2* Transceiver T1IN connects to the level translator JU3 OPEN Transceiver T1IN disconnects from the level translator 1-2* Transceiver T2IN connects to the level translator JU4 OPEN Transceiver T2IN disconnects from the level translator 1-2* Transceiver R1OUT connects to the level translator JU5 OPEN Transceiver R1OUT disconnects from the level translator 1-2* Transceiver R2OUT connects to the level translator JU6 OPEN Transceiver R2OUT disconnects from the level translator 1-2 Transceiver T2IN connects to Arduino/Mbed connectors D0 signal JU1D0 2-3* Transceiver R2OUT connects to Arduino/Mbed connectors D0 signal OPEN Arduino/Mbed connectors D0 signal is not connected 1-2* Transceiver T2IN connects to Arduino/Mbed connectors D1 signal JU1D1 2-3 Transceiver R2OUT connects to Arduino/Mbed connectors D1 signal OPEN Arduino/Mbed connectors D1 signal is not connected 1-2 Transceiver T2IN connects to Arduino/Mbed connectors D2 signal JU1D2 2-3 Transceiver R2OUT connects to Arduino/Mbed connectors D2 signal OPEN* Arduino/Mbed connectors D2 signal is not connected Maxim Integrated 2 www.maximintegrated.com