Comments on: JTAG Defined | An Introduction to JTAG http://www.etoolsmiths.com/blog/jtag-defined/ JTAG and Boundary-Scan Tools Fri, 22 Jul 2011 22:05:47 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: admin http://www.etoolsmiths.com/blog/jtag-defined/#comment-6541 admin Fri, 22 Jul 2011 22:05:47 +0000 http://www.etoolsmiths.com/blog/?p=11#comment-6541 HI, Thanks for the questions. The typical impedance for TCK (the most important signal for reliable operation) is 50 Ω. The voltage levels are device dependent common ranges from 1.1v to 5v. Data rates are also device dependent. For example, if multiple devices are in a chain, the max speed is limited by the slowest device in the chain. The max TCK for any device is supplied by te manufacturer and is found in the BSDL file describing the device. For ESD protection a diode like the one below is typically used: http://www.maxim-ic.com/solutions/esd_protection/parts.mvp/scpk/1512/pl_pk/0 Thanks Pat HI,
Thanks for the questions.
The typical impedance for TCK (the most important signal for reliable operation) is 50 Ω. The voltage levels are device dependent common ranges from 1.1v to 5v.

Data rates are also device dependent. For example, if multiple devices are in a chain, the max speed is limited by the slowest device in the chain. The max TCK for any device is supplied by te manufacturer and is found in the BSDL file describing the device.

For ESD protection a diode like the one below is typically used:
http://www.maxim-ic.com/solutions/esd_protection/parts.mvp/scpk/1512/pl_pk/0

Thanks
Pat

]]> By: C.M.Garland http://www.etoolsmiths.com/blog/jtag-defined/#comment-2881 C.M.Garland Tue, 13 Jul 2010 01:06:49 +0000 http://www.etoolsmiths.com/blog/?p=11#comment-2881 What are the signal levels, data rates and line impedances for the Test Access Ports?. Are there any recommendations for Transient & ESD protection of the TAPs? What are the signal levels, data rates and line impedances for the Test Access Ports?. Are there any recommendations for Transient & ESD protection of the TAPs?

]]> By: JTAG Connector Pinouts http://www.etoolsmiths.com/blog/jtag-defined/#comment-1850 JTAG Connector Pinouts Tue, 21 Jul 2009 05:21:47 +0000 http://www.etoolsmiths.com/blog/?p=11#comment-1850 [...] JTAG Signals [...] [...] JTAG Signals [...]

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