XJExtender

Overview
Benefits
Features
Details

XJExtender is XJTAG’s recommended solution to overcome signal integrity issues when connecting an XJLink JTAG controller to a remote Unit Under Test (UUT). By using differential signalling, XJExtender allows you to work with a UUT up to 10 metres from the XJLink, even in electrically noisy environments.

Key Benefits

Reliably extends the distance between JTAG Controller and UUT

Allows UUT testing in larger installations or environmental chambers

Provides superior EMI immunity to preserve signal integrity

Improves the overall performance of test systems · Compatible with other XJTAG hardware including XJIsolator and XJXDP

Features

Standard 26-way IDC connectors support cost-effective ribbon cable for board-to-board connection (twisted-pair ribbon cable recommended for best performance)
TCK clock frequencies up to 50 MHz
Flexible power supply voltage: 5 V to 15 V (2 required, not included)
Variable I/O voltage from 1.8 V to 3.3 V (when used with XJLink2)
Provides 8 channels configurable as uplink or downlink (default configuration: 6 downlink/2 uplink)
Controller unit plugs directly into JTAG controller via standard 20-way IDC interface
Target unit connects directly to UUT using standard 20-way IDC socket

Extending performance

Poor signal integrity between a JTAG controller and the UUT may force you to reduce TCK frequencies, or even stop you running tests.

The high levels of electrical noise that often exist in test environments can cause signal integrity problems when running JTAG tests; problems that can be made worse if a UUT has to be placed away from the JTAG controller, in a fixture or an environmental chamber.

XJExtender overcomes these issues by supporting cables up to 10 metres long without compromising signal integrity.

Flexible configuration

XJExtender comprises a Controller unit connected directly to a JTAG controller, and a Target unit connected to the UUT. Target units can be purchased separately to support workflows that require Target units to be permanently located within test fixtures.

Each unit offers 8 channels with a default configuration of 6 downlink (Controller to Target) and 2 uplink (Target to Controller). This can be reconfigured using on-board solder links to any combination of uplink/downlink channels.

Extending signal integrity

Using the Low Voltage Differential Signalling (LVDS) standard as the physical layer between the Controller and Target, XJExtender allows high speed communications over flat or twisted-pair ribbon cables.

As each channel uses differential signalling, the cable generates low levels of Electromagnetic Radiation (EMR); important when testing sensitive electronic assemblies. It also exhibits very high immunity to Electromagnetic Interference (EMI), which enables the use of longer cables without loss of signal integrity.

Extended temperature range

XJExtender units support a temperature range of -40 °C to +85 °C. This makes XJExtender the ideal solution for testing a UUT in an environmental chamber.