DO-CPLD-DK-J-G Xilinx Inc, DO-CPLD-DK-J-G Datasheet - Page 23

• Manufacturer Part Number: DO-CPLD-DK-J-G
• Description: KIT STARTER CPLD JAPANESE
• Manufacturer: Xilinx Inc
• Series: CoolRunner™- IIr
• Type: CPLD Development Kitr

Specifications of DO-CPLD-DK-J-G

• Contents: Proto Board, Download Cable, Software and Documentation
• For Use With/related Products: CoolRunner-ll, XC9500XL
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

CPLD I/O User Guide
UG445 (v1.1) November 27, 2007
Slew Rate
R
Non-Schmitt Waveforms
In
noise from the outputs that make the non-Schmitt Trigger input appear jagged.
When the input is higher than a certain chosen threshold, the output is high; when the
input is below another (lower) threshold, the output is low; when the input is between the
two, the output retains its value. Thus, the output retains its value until the input changes
sufficiently to trigger a change. This dual-threshold action is called “hysteresis”.
The hysteresis for the CoolRunner-II Schmitt trigger is reported in the data sheet. One
point to note is that the Vt+ min and Vt- max are equal. However, this combination will not
happen together as the Vt levels track each other. When looking at the Vt max of one
characteristic, you must look at the Vt max of the other.
For more information on the CoolRunner-II Schmitt trigger, see the CoolRunner-II I/O
Characteristics Application Note (XAPP382).
The slew rate for outputs can be selected as either fast or slow. A slow slew rate is a
delayed version of the fast slew rate. The change in the slew rate is achieved by delaying
the fast slew rate output.
Figure 8
Figure 8: Before and After Schmitt Trigger Waveforms
are two waveforms of a signal with and without the Schmitt Trigger, it is the
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Power, Sequencing, and Slew Rates
Schmitt Waveforms
UG445_07_052207
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