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Altera Corporation
APEX 20K Programmable Logic Device Family Data Sheet
Preliminary Information
Notes to table:
(1)
To implement the ClockLock and ClockBoost circuitry with the Quartus software, designers must specify the input
frequency. The Quartus software tunes the PLL in the ClockLock and ClockBoost circuitry to this frequency. The
fCLKDEV parameter specifies how much the incoming clock can differ from the specified frequency during device
operation. Simulation does not reflect this parameter.
(2)
Twenty-five thousand parts per million (PPM) equates to 2.5% of input clock period.
(3)
During device configuration, the ClockLock and ClockBoost circuitry is configured before the rest of the device. If
the incoming clock is supplied during configuration, the ClockLock and ClockBoost circuitry locks during
configuration because the tLOCK value is less than the time required for configuration.
(4)
The tJITTER specification is measured under long-term observation. The maximum value for tJITTER is 200 ps if
tINCLKSTB is lower than 50 ps.
SignalTap
Embedded
Logic Analyzer
APEX 20K devices include device enhancements to support the SignalTap
embedded logic analyzer. By including this circuitry, the APEX 20K
device provides the ability to monitor design operation over a period of
time through the IEEE Std. 1149.1 (JTAG) circuitry; a designer can analyze
internal logic at speed without bringing internal signals to the I/O pins.
This feature is particularly important for advanced packages such as
FineLine BGA packages, because it can be difficult to add a connection to
a pin during the debugging process after a board is designed and
manufactured.
IEEE Std.
1149.1 (JTAG)
Boundary-Scan
Support
All APEX 20K devices provide JTAG BST circuitry that complies with the
IEEE Std. 1149.1-1990 specification. JTAG boundary-scan testing can be
performed before or after configuration, but not during configuration.
APEX 20K devices can also use the JTAG port for configuration with the
Quartus software or via hardware using Jam Files (.jam) or Jam
Byte-Code Files (.jbc). Finally, APEX 20K devices use the JTAG port to
monitor the logic operation of the device with the SignalTap embedded
logic analyzer. APEX 20K devices support the JTAG instructions shown in