USERS MANUAL ISL41334EVAL1Z AN1259 Rev 0.00 Evaluation Board May 31, 2006 In most cases, a name that applies to both products contains Description no parenthesis (e.g., B1), a name that applies to only the The ISL41334 evaluation board is RoHS compliant, and ISL41334 is followed by (NC) (e.g., B2 (NC)), and a name provides a quick and easy method for evaluating this two that applies to only the ISL41387 is preceded by NC and/or port Dual Protocol IC. The eval board also accommodates has the name in parenthesis (e.g., NC (DEN) or (DEN)). the ISL41387 see the ISL41387EVAL1Z Users Manual for Note that on Rev. A of these boards the following minor details. errors have been noted, and are corrected on subsequent This board was designed to allow the user to evaluate all the revisions: features available on the ISL81334 and ISL41334 products. Jumper label A2/Y2 LB (9) should be B2/Z2 LB. The ISL41334 is the full featured version (see Features below), where the QFN packages increased pin count gives Jumper label B2/Z2 LB (10) should be A2/Y2 LB. the user access to functionality not available on the pin Jumper labels J-SELX (7 and 8) should be J-SELX limited ISL81334. The same die is used in both products, so (NC) because they are not used for the ISL41387. other than minor package effects, evaluating the QFN packaged ISL41334 is a reasonable substitute for evaluating Jumper label J-RXEN2 (18) should be J-RXEN2 (NC) the ISL81334. because it is not used for the ISL41387. Jumper label J-RXEN (not numbered) should be By changing jumper positions the user can quickly set the J-(RXEN) because it is only used for the ISL41387. board to evaluate any of the ISL41334s many modes and features, and the input states can also be set via jumpers. Jumper label J-DE2 (19) should be J-DE2 (NC) because it is not used for the ISL41387. Refer to the data sheet for complete details regarding the functions and features of this device. These dual protocol Jumper label J-DY2 (20) should be J-DY2 (NC) ICs feature many modes, so studying the devices truth-table because it is not used for the ISL41387. along with its operating circuits and detailed description is (21) should be J-ON/OFF (NC) Jumper label J-ON/OFF the best way to gain an understanding of how the part works. because it is not used for the ISL41387. Jumper label J-(SLEW) (23) should be J-DY1 (SLEW). Features Jumper label J-DE1 (24) should be J-DZ1/DE1 (DY). QFN Version Demonstrates All Enhanced Features: It is important to note that the ISLX1334 dont follow the Logic Supply Pin (V ) L Three RS-485 Speed Options - 115kbps/460kbps/20Mbps RS-485 convention whereby the inverting I/O is labeled Active Low RS-485 Rx Enable for Simple Direction Control B/Z, and the noninverting I/O is A/Y. Thus, the ISL41334 A/Y (B/Z) pins connect to the B/Z (A/Y) pins of generic Quick Configuration Using Jumpers RS-485/422 ICs. State of All Inputs Can be Set by Jumper Positions Input signals that connect to a BNC connector, because they No Bus Termination Resistors on Port 1 Allows Easy are likely to be driven by a generator, include a 50 RS-232 Evaluation Bus Termination Resistors on Port 2 termination resistor to GND when the jumper is in the LOW for RS-485 Evaluation position. Simple Operation Requires Only One, 5V, Power Supply Port 1 includes no Rx input nor Tx output termination resistors, as this port is intended for RS-232 evaluation. Important Notes Port 2, intended for RS-485/422 evaluation, includes 120 To facilitate locating jumpers on this board, Figure 3 is a differential termination resistors across the Rx inputs, and jumper locator and, in this App Note, the ( ) following a across the Tx outputs. jumper mention corresponds to the red jumper number on the locator. See the Jumper Definitions section for a Default Configuration description of the function of each jumper. As delivered (see Functional Diagram), the board is The base board is used to evaluate both the ISL41334 (2 port) configured for port 1 in RS-232 mode with Tx and Rx and ISL41387 (1 port) products, so the jumper and connector enabled (Tx is always enabled in RS-232 mode), Rx inputs names reflect the functionality of both products. Due to space floating, and Tx inputs low. Port 2 is in RS-485 mode with Tx limitations some jumper labels are abbreviated, but the and Rx enabled, Tx set for high speed (20Mbps) operation, corresponding BNC connector has the full label. driver input (DY) low, Rx inputs floating but shorted together AN1259 Rev 0.00 Page 1 of 10 May 31, 2006ISL41334EVAL1Z through a 120 termination resistor. Additionally, the V+ - Used to monitor the positive charge pump voltage in RS-232 mode. ISL41334 is powered-up (i.e., not SHDN), has internal loopback disabled, and has V shorted to V . To achieve L CC V- - Used to monitor the negative charge pump voltage in this configuration, the jumpers are installed as follows RS-232 mode. (unlisted jumpers are not installed, and ( ) indicates the VCC - The 5V supply connection. jumper number on the Figure 3 jumper locator): VHIGH - Connects to all the VH positions on the jumpers to SEL1 (7) = LOW SEL2 (8) = VH RXEN1 (15) = LOW define the high level voltage for logic and Tx inputs the SPA (16) = VH SPB (17) =VH RXEN2 (18)=LOW VL-VHIGH (27) jumper shorts this jack to V , so remove L DE2 (19) =VH DY2 (20) = LOW ON/OFF (21) =VH this jumper if supplying a voltage other than V . L LB (22) = VH DY1 (DZ/SLEW) (23)=LOW VL - The logic supply voltage that sets the ISL41334s Rx DZ1/DE1 (DY) (24) = LOW RXBIAS-VCC (25) = installed output V levels, and the logic and Tx input switching VCC-VL (26) = installed VL-VHIGH (27) = installed. OH points the VCC-VL (26) jumper shorts this jack to V , CC so remove this jumper if supplying a voltage other than Functional Diagram (Default Configuration) V . CC (26) (27) VHIGH (V ) +5V H + 0.1 F Getting Started 34 31 37 C 1 C1+ V 1 V + CC L C Connect a 5V, 500mA minimum, power supply to the V + 3 V+ CC 0.1 F 38 0.1 F C1- and GND banana jacks. It is recommended that an ammeter 36 C 2 C2+ + 19 0.1 F C 35 V- 4 be used between the supply and the board, so that I can CC C2- 0.1 F + be monitored. Ensure that the RXBIAS-VCC (25), R 29 2 A1 A1 R VCC-VL (26) and VL-VHIGH (27) jumpers are installed in 5k the upper right hand corner of the board. 17 RXEN1 B1 3 R R 30 5k For simplicity, the following discussions assume that port 1 is B1 used for RS-232 evaluations, and port 2 for RS-485 D Y1 4 Y1 27 D evaluations. Of course, the user is free to configure either port for either protocol. D 5 Z1 Z1 28 D External Loopback Via Jumpers 6 SEL1 To evaluate the Rx and Tx performance at the same time, an 25 7 ON/OFF V V H H SEL2 external loopback can be implemented simply by installing 26 V LB H jumpers A1/Y1 LB (5) and B1/Z1 LB (6) for port 1, and 11 A2 R A2 22 jumpers A2/Y2 LB (10) and B2/Z2 LB (9) (note swapped 120 R 10 B2 18 labeling on rev A boards) for port 2. In this configuration, the RXEN2 Tx output lines connect to the corresponding Rx input lines, 9 Y2 D 24 Y2 so the data driven on the Tx input(s) appears at the Rx 120 D 8 Z2 output(s). In RS-485 mode, data driven on DY loops back 13 V 23 H SPA DE2 V through A and B to R . In RS-232 mode, DY loops back to 14 H A V H SPB GND R , and DZ loops back to R . A B 15. 16 Basic RS-485 DC Evaluation (Port 2) General Observations Supply Banana Jacks I should be approximately 34mA. Most of this current is CC There are eight banana jacks at the top of the board for due to the RS-485 Tx driving the 120 termination resistor power supply connections, but only V and GND are CC (R13). To get just the quiescent ISL41334 I , simply move CC required connections. The function and use of each jack jumper DE2 (19) to theLO position. I should now be CC (from left to right) is: approximately 3.4mA, due to the charge pumps running to provide the RS-232 transmitter supplies for port 1. Move VLOAD - This is a load voltage driving the load resistors connected to the Rx and Tx outputs (Tx resistors - R5, R6, jumper DE2 back to the VH position. R10, R11 - are not populated) used mostly during output Measure V+ and V- at the banana jacks - V+ +6V and enable and disable time characterizations. V- -7V, indicating that the charge pumps are on. If both ports were programmed for RS-485 mode, then I drops to GND - Common connection for any supplies used. CC 1.3mA (if DE2 = LOW), and V+ V , V- = GND. CC RXBIAS - A voltage that can be applied to any or all Rx inputs via jumpers ((2), (3), (11), (12)) the RXBIAS-VCC , so remove this jumper (25) jumper shorts this jack to V CC if supplying a voltage other than V . CC AN1259 Rev 0.00 Page 2 of 10 May 31, 2006