DC1843B Analog Devices

DEMO MANUAL DC1843B DC1842B and DC1680B LTC4290B/LTC4271 8-Port PSE with Digital Isolation DESCRIPTION Demonstration kit DC1843B is an 8-port Ethernet Alliance printouts. Refer to the Layout Guide for Demonstration certified IEEE 802.3at Type 2 power sourcing equipment Circuit 1842B when laying out the LTC4290B/LTC4271 (PSE) composed of a DC1842B daughter card and DC1680B circuit. Contact Analog Devices for this document. motherboard. The kit is used for evaluation of the LTC4290B The DC1842B has increased surge protection over the and LTC4271 PSE chipset. Up to 8 powered devices (PDs) DC1842A. The DC1680B uses discrete Ethernet transform- can be connected and powered from this system using a ers while the DC1680A has an integrated 12-port RJ45 jack. single power supply. A DC590 is connected to the DC1843 2 Design files for this circuit board are available. for I C interfacing with QuikEval. This demonstration manual provides a Quick Start Procedure, a DC1842B All registered trademarks and trademarks are the property of their respective owners. overview, a DC1680B overview, schematics, and layout BOARD PHOTO Rev B 1DEMO MANUAL DC1843B QUICK START PROCEDURE Demonstration kit DC1843B includes the DC1842B 3. Align pin 1 of the 30-pin male connector on the DC1842B with pin 1 of the 30-pin female connector on the daughter card and DC1680B motherboard. The kit is set DC1680B (Figure 2). Pin 12 is polarized to assist with the up for evaluating the LTC4290B/LTC4271. Follow the pro- alignment. Carefully push the DC1842B straight down cedure below and refer to Figures 1 through 4 for proper until the two 30-pin connectors are flush with each other. equipment setup. 4. On the DC1680B, connect a supply with the positive NOTE (DC1843B Kit): Connector J1 on the DC1680B has rail to POS and negative rail to NEG (Figure 3). Use a four pegs blocking the unused last four pins to match the power supply capable of sourcing the maximum load 30-pin connector of the DC1842B. Dust caps block the four expected (8 ports 850mA 6.8A). Ramp the supply unused ports at each RJ45 connector on the DC1680B up to 51V to 57V. for the 8-Port. 5. Connect up to 8 PDs to ports 1-8 at the DC1680B, J4 1. On the DC1842B set AUTO jumper JP1 to HI (Figure 1) (Figure 3). to enable AUTO pin mode. 6. The DC590 is optionally connected to the DC1680B con- 2. On the DC1842B set MID jumper JP2 to LO (Figure 1) nector J5 with a 14-pin ribbon cable (Figure 3). A GUI to disable midspan mode. for the LTC4290B/LTC4271 is brought up by QuikEval 2 for I C interfacing from a PC (Figure 4). www.analog.com ADI Figure 1. DC1842 Backside. Setting AUTO and MID Jumpers Figure 2. Inserting the DC1842 into J1 of the DC1680 Rev B 2