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Overview

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Overview

This EVM allows for evaluation of either the ISO1176T PROFIBUS™ or ISO35T or ISO3086T RS-485
transceivers. The EVM comes with a single transceiver installed on the circuit board (U1), but any of the
three devices can be evaluated using this single printed-circuit board (PCB). The PCB also contains a
transformer and voltage regulator that is used to provide dc power to the right (bus) side of the device.
Because all three devices contain the output oscillator signals used to drive the transformer, any of the
three devices can be evaluated using this single PCB. Note that two different transformers and voltage
regulators can be installed on the PCB. One set is used to ge3.3 Vdc for the ISO35T device,
which is specified for 3.3-Vdc operation. The other set is installed on the ISO1176TEVM and
ISO3086TEVM to ge5-Vdc power required for those two devices. These three integrated circuits
(ISO1176T, ISO35T, and ISO3086T) all contain the integrated transformer driver and are footprint
compatible. The major difference is the +5-Vdc or +3.3-Vdc operation.

Care needs to be taken regarding the isolated power and ground, as this is an isolating device. Power and
ground for the Data/Control side of the device (pins D, R, DE, RE\, D1, and D2) can be completely
isolated from power and ground for the Bus side of the device (pins A, B, etc.). Although these devices are
designed to operate with an isolation voltage up to 4000 V, this PCB is not. To ensure user safety while
using the EVM, the PCB has been designed to support an isolation voltage of approximately 500 V. The
user must be careful when using the EVM to test isolation voltage.

Finally, the ISO1176TEVM allows half-duplex operation, whereas the ISO35T and ISO3086T are
full-duplex devices. The PCBs are configured for either half- or full-duplex operation in their as-shipped
configuration. Changes between configurations can easily be done using the notes provided on the
schematic. The EVMs allow the user to evaluate half-duplex point-to-point or multidrop (PROFIBUS)
systems, or multipoint (RS-485) applications using multiple EVMs.

The ISO1176T meets or exceeds the requirements of EN50170 and the ISO35T and ISO3086T meet or
exceed the requirements of TIA/EIA RS-485 while providing 4000 V of isolation between the Data/Control
and Bus sides of the device. Each device has specific features, such as receiver hysteresis, low bus
capacitance, and failsafe receiver output for bus open, short, or idle conditions. These devices also
support extremely fast data rates or 1 Mbps (ISO35T), 20 Mbps (ISO3086T), or 40 Mbps (ISO1176T).
These features all contribute to making the ISO1176T, ISO35T, or ISO3086T an excellent choice for use
in industrial and factory environments.

CAUTION

Note that although the device provides galvanic isolation of up to 4000 V, this
EVM cannot be used for isolation voltage testing. It is designed for the
examination of device operating parameters only and may be damaged if high
voltage (>500 V) is applied across the isolation barrier or if a voltage >5.5 V is
applied to any device pin.

The data sheet for three devices is available on the TI Web site. A pinout of each device and functional
block diagram are in

Figure 1

through

Figure 3

.

PROFIBUS is a trademark of PROFIBUS Nutzerorganisation e V.

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ISO1176T/35T/3086T Evaluation Module

SLLU122A – April 2010 – Revised July 2010

Copyright © 2010, Texas Instruments Incorporated

Summary of Contents for ISO1176T

Page 1: ...th a tool for evaluation and the successful design of an end product Contents 1 Overview 2 2 Recommended Equipment 8 List of Figures 1 ISO1176T Device Pinout and Block Diagram 3 2 ISO35T Device Pinout and Block Diagram 3 3 ISO3086T Device Pinout and Block Diagram 3 4 ISO1176T 35T 3086TEVM Board 5 5 Point to Point Simplex Circuit 6 6 Parallel Terminated Simplex Circuit 6 7 Five Node Multipoint Circ...

Page 2: ... careful when using the EVM to test isolation voltage Finally the ISO1176TEVM allows half duplex operation whereas the ISO35T and ISO3086T are full duplex devices The PCBs are configured for either half or full duplex operation in their as shipped configuration Changes between configurations can easily be done using the notes provided on the schematic The EVMs allow the user to evaluate half duple...

Page 3: ...re 2 ISO35T Device Pinout and Block Diagram Figure 3 ISO3086T Device Pinout and Block Diagram 1 1 PROFIBUS RS 485 The TIA EIA 485 also known as RS 485 standard was created in response to a demand from the data communications community for a general purpose high speed balanced interface standard for multipoint applications The standard Electrical Characteristics of Generators and Receivers for Use ...

Page 4: ...cifically for these types of environments The two standards are indeed very similar 1 2 EVM Kit Contents 1 2 1 ISO1176TEVM Kit Contents ISO1176TEVM circuit board with ISO1176TDW installed 6510416 1 This PCB is configured with a DA2304 AL transformer and LP2985A 50DBVR LDO for 3 V to 5 V operation on the logic side of the device and 5 V operation on the bus side 1 2 2 ISO35TEVM Kit Contents ISO35TE...

Page 5: ...e EVMs can be obtained to allow the user to construct various bus configurations With just two EVMs the user may evaluate performance of a point to point simplex parallel terminated point to point simplex and two node multipoint operation When using multiple EVMs all of these modes of operation can be configured through onboard jumpers external cabling and the R7 R10 resistors 5 SLLU122A April 201...

Page 6: ... tied to GND1 Note that with only a single termination the differential bus voltage is higher than normal Figure 5 Point to Point Simplex Circuit This configuration also can have a termination at the source and load parallel terminated as shown Figure 6 thereby keeping nominal PROFIBUS RS 485 signal levels Figure 6 Parallel Terminated Simplex Circuit 1 3 2 Multipoint The multipoint configuration i...

Page 7: ...y This extended common mode range is important because communications between equipment located hundreds of meters apart usually means a voltage offset exists between the grounds of each node The EVMs can be configured with three power supplies with isolated outputs in such a way as to input a fixed offset between the grounds see Figure 7 This induces a ground potential difference voltage VGPD bet...

Page 8: ... configured for each case 2 1 EVM Configurations The schematic for the ISO1176TEVM appears on the last page of this manual Table 1 contains a list of the onboard jumpers and their function as well as the input and output loading installed on the board for the half duplex ISO1176TEVM Table 2 contains the same information for the full duplex ISO35TEVM and ISO3086TEVM Table 1 EVM Configuration Option...

Page 9: ...T device R9 54 Ω only R7 R8 AND R10 R7 R8 and R10 for full duplex are uninstalled device Table 2 EVM Configuration Options for ISO35T and ISO3086T Jumper Function Configuration I O Load DATA CONTROL SIDE JUMPERS JMP1 Receiver Output R1 see JMP16 JMP2 Receiver Enable R2 50 Ω 1 JMP3 Driver Enable R3 50 Ω 1 JMP4 Driver Input R4 50 Ω 1 R7 Uninstalled JMP6 D1 D2 Test Point JMP16 Rout Load Jumper short ...

Page 10: ... Table 5 Table 3 ISO1176TEVM Bill of Material Item Qty Reference Value Footprint Manufacturer Part Number 1 1 C2 68 µF cc7260 SPRAGUE 592D68X0010R2T 2 1 C3 10 µF cc7343 SPRAGUE 293D106X0035D2W 3 1 C4 1 µF cc1206 AVX 12063G105ZATRA 4 1 C5 0 1 µF cc1206 AVX 12065C104JATMA 5 1 C6 0 01 µF cc0805 AVX 06033G102JATMA 6 1 C7 DNI cc0805 7 2 C15 C17 10 µF cc1206 8 1 C16 22 µF cc1210 9 2 D1 D2 1N5817 10 10 J...

Page 11: ...35T 20 1 U3 LP2985A 33DBVR SOT23 5 TI LP2985A 33DBVR Table 5 ISO3086TEVM Bill of Materials Item QTY Reference Value Footprint Manufacturer Part Number 1 1 C2 68 µF cc7260 SPRAGUE 592D68X0010R2T 2 1 C3 10 µF cc7343 SPRAGUE 293D106X0035D2W 3 1 C4 1 µF cc1206 AVX 12063G105ZATRA 4 1 C5 0 1 µF cc1206 AVX 12065C104JATMA 5 1 C6 0 01 µF cc0805 AVX 06033G102JATMA 6 1 C7 DNI cc0805 7 2 C15 C17 10 µF cc1206 ...

Page 12: ...ignal routing The remaining layers Figure 11 and Figure 13 are power and ground planes These are split planes to keep the Vcc1 GND1 separate from Vcc2 GND2 The I O traces are designed to have a characteristic impedance of 50 Ω Figure 10 PCB Top Layer 12 ISO1176T 35T 3086T Evaluation Module SLLU122A April 2010 Revised July 2010 Copyright 2010 Texas Instruments Incorporated ...

Page 13: ...www ti com Recommended Equipment Figure 11 Silk Screen Top Side 13 SLLU122A April 2010 Revised July 2010 ISO1176T 35T 3086T Evaluation Module Copyright 2010 Texas Instruments Incorporated ...

Page 14: ...Recommended Equipment www ti com Figure 12 Signal Traces Bottom Layer 14 ISO1176T 35T 3086T Evaluation Module SLLU122A April 2010 Revised July 2010 Copyright 2010 Texas Instruments Incorporated ...

Page 15: ...www ti com Recommended Equipment Figure 13 Silkscreen Bottom Layer 15 SLLU122A April 2010 Revised July 2010 ISO1176T 35T 3086T Evaluation Module Copyright 2010 Texas Instruments Incorporated ...

Page 16: ...2 Enable 3 NR 4 Vout 5 Vin 1 C17 10uF C17 10uF C7 DNI C7 DNI C3 10 uF C3 10 uF JMP25 Header 3x1 JMP25 Header 3x1 1 2 3 JMP29 Header 3x1 JMP29 Header 3x1 1 2 3 JMP6 Header 4x1 JMP6 Header 4x1 1 2 3 4 T1 DA2303_AL T1 DA2303_AL 1 2 3 4 5 6 7 8 JMP28 Header 3x1 JMP28 Header 3x1 1 2 3 JMP4 Header 4x1 JMP4 Header 4x1 1 2 3 4 JMP32 Header 2x1 JMP32 Header 2x1 1 2 JMP1 Header 3x1 JMP1 Header 3x1 1 2 3 C4 ...

Page 17: ...roduct This notice contains important safety information about temperatures and voltages For additional information on TI s environmental and or safety programs please contact the TI application engineer or visit www ti com esh No license is granted under any patent right or other intellectual property right of TI covering or relating to any machine process or combination in which such TI products...

Page 18: ...ch statements TI products are not authorized for use in safety critical applications such as life support where a failure of the TI product would reasonably be expected to cause severe personal injury or death unless officers of the parties have executed an agreement specifically governing such use Buyers represent that they have all necessary expertise in the safety and regulatory ramifications o...

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