Click here for production status of specific part numbers. Evaluates: MAX14775E/MAX14776E MAX14775E Evaluation Kit Startup Procedure General Description The EV kit is fully assembled and tested. Follow the steps The MAX14775E evaluation kit (EV kit) is a fully assembled below to verify board operation. and tested PCB that demonstrates the functionality of the MAX14775 20Mbps RS-485/RS-422 fault-protected 1) Set the DC power supply to 3.3V and connect the transceiver. DC power supply between the VCC and GND connectors on the EV kit. The MAX14775E EV kit may also be used to evaluate the 2) Ensure that all jumpers are in their default positions MAX14776E. (see Table 1). 3) Connect the oscilloscope probes to the A, B, and RO Features test points on the EV kit. Operates From a Single 3V to 5V Supply 4) Turn on the power supply. Terminal Block Connectors for Easy RS-485/RS-422 5) Set the signal/function generator to output a 1MHz Evaluation 0-to-3.3V square wave. Fully Assembled and Tested 6) Connect the signal/function generator to the DI test point. Quick Start 7) Using the oscilloscope, verify that the A, B and RO outputs switch as the signal on DI toggles. Required Equipment MAX14775E EV kit 3.3V, 500mA DC power supply Signal/function generator Oscilloscope Ordering Information appears at end of data sheet. 19-8706 Rev 1 10/18Evaluates: MAX14775E/MAX14776E MAX14775E Evaluation Kit Table 1. Jumper Table (J1-J5) Detailed Description of Hardware The EV kit is a fully assembled and tested circuit board for SHUNT PO- JUMPER DESCRIPTION SITION evaluating the MAX14775E high speed RS-485/RS-422 transceiver (U1). The EV kit has been designed to allow DE and RE are not connected Open* for evaluating the MAX14775E alone or in a standard together. J1 RS-485 network. DE and RE are connected Closed together. Driver and Receiver Enable Selection A and B are connected through The EV kit features three jumpers (J1, J4, and J5) to Open* the on-board 120 termination enable/disable the driver and receiver outputs. Set J4 resistor. to 2-3 to enable the receiver. Set J5 to 1-2 to enable the J2 driver. To actively control both enables, remove J4 and J5 A and B are not connected shunts and close J1, which connects DE and RE together. Closed through the on-board termina- tion resistor. Resistors R2R4 Configuration RE is high. The RS-485 receiver For end-of-the-line transceivers, close J2 to connect 1-2 is disabled. a 120 termination resistor (R2) between the A and B J4 RE is low. The RS-485 receiver RS-485 receiver inputs on the MAX14775E. 2-3* is enabled. Pullup and pulldown resistors are generally used on the DE is high. The RS-485 driver receiver inputs to guarantee a known state in the event 1-2* outputs are enabled. that all nodes on the bus are in receive mode, or the J5 cable becomes disconnected. The exact value for these DE is low. The RS-485 driver 2-3 resistors will vary with the application. R1 and R3 pads are outputs are disabled. provided for pullup and pulldown resistors on the A and *Default position. B lines, if needed. The use of any of these resistors is purely optional. Note that the MAX14775E features true fail-safe receiver inputs, which ensures that RO is high when the receiver inputs are shorted, open, or connected Ordering Information to an idle bus. PART TYPE Surge Protection MAX14775EEVKIT EV Kit Some industrial applications require extra components on the A and B lines to protect against high voltage surges. Denotes RoHS compliant. Pads for D1 and D2 TVS diodes are included on the MAX14775E EV kit for this purpose. The use of these diodes is completely optional for normal operation. Maxim Integrated 2 www.maximintegrated.com