MAX22500EEVKIT# Analog Devices

Evaluates: MAX22500E MAX22500E Evaluation Kit Startup Procedure General Description The EV kit is fully assembled and tested. Follow the steps The MAX22500E evaluation kit (EV kit) is a fully assembled below to verify board operation. and tested PCB that demonstrates the functionality of the MAX22500E half-duplex high speed RS-485/RS-422 1) Ensure that all jumpers are in their default positions transceiver with preemphasis functionality. The EV kit (see Table 1). operates from a single 5V supply and includes on-board 2) Set the DC power supply to 5V and connect the DC termination. power supply to the VCC test point. Connect the ground terminal of the 5V supply to the GND test point. Features 3) Turn on the power supply. Operates From a Single 5V Supply 4) Set the signal/function generator to output a 30MHz 0-to-5V square wave. Terminal Block and RJ45 Connectors for Easy 5) Connect the signal/function generator to the DI test RS-485/RS-422 Evaluation point. On-board Selectable Preemphasis Setting 6) Using the oscilloscope, verify that the A, B, and RO Fully Assembled and Tested outputs switch as expected with the signal on DI. Quick Start Required Equipment MAX22500E EV kit 5V, 500mA DC power supply 80MHz signal/function generator Oscilloscope Ordering Information appears at end of data sheet. 319-100048 Rev 0 8/17 PRELIMINARYEvaluates: MAX22500E MAX22500E Evaluation Kit Driver and Receiver Enable Detailed Description of Hardware The EV kit features three jumpers (J3, J5, and J8) to The MAX22500E EV kit is a fully assembled and tested enable/disable the driver and receiver outputs. Set J3 to circuit board for evaluating the MAX22500E high-speed, low (2-3) to enable the receiver. Set J3 to high (1-2) to half-duplex RS-485/RS-422 transceiver (U1). The EV enable the driver. kit is powered from a single 5V power supply and can be used for standalone evaluation or can be connected To actively control both enables, remove the J2 and (using the on-board terminal block) to an RS-485/RS-422 J3 jumpers and close J4, which connects DE and RE network for easy in-system evaluation. together. Powering the Board Setting the Preemphasis The MAX22500E operates from a 5V voltage supply. The The MAX22500E features integrated driver preemphasis device also includes a separate logic supply input (VL) to circuitry for reliable communication higher data rates over interface with logic signal as low as 1.6V. longer distances. Preemphasis is set with by connecting a resistor between PSET and ground. Close the J4 jumper to connect VL to VCC (VL = 5V), to operate the EV kit with a single supply. The MAX22500E EV kit includes a 15k to set the preemphasis for a 30Mbps data rate. Set the switch Open the J4 jumper and connect a separate logic supply (SW1) to the on position to enable preemphasis. To disable to the VL test point (TP6) to operate with a supply logic preemphasis, set SW1 to the off position. lower than 5V. Termination for an End-of-Line Transceiver The MAX22500E EV kit includes a 120 termination resistor (R7) between the A and B RS-485 receiver inputs on the MAX22500E. Maxim Integrated 2 www.maximintegrated.com PRELIMINARY