EP2SGX30CF780C5N Datasheet, PDF (143/316 Pages) Altera Corporation – Section I. Stratix II GX Device Data Sheet

Stratix II GX Architecture
Table 2–36 contains board design recommendations to ensure that nCEO
can successfully drive nCE for all power supply combinations.
Table 2–36. Board Design Recommendations for nCEO and nCE Input Buffer Power
nCE Input Buffer Power in
Stratix II GX nCEO V_CCIO Voltage Level in I/O Bank 7
I/O Bank 3
V_{C C I O} = 3.3 V V_{C C I O} = 2.5 V V_{C C I O} = 1.8 V V_{C C I O} = 1.5 V V_{C C I O} = 1.2 V
VCCSEL high
(V_{C C I O} Bank 3 = 1.5 V)
VCCSEL high
(V_{C C I O} Bank 3 = 1.8 V)
v(1), (2)
v (1), (2)
v (3), (4)
v (3), (4)
v (5)
v
v
v
v
Level shifter
required
VCCSEL low (nCE powered
v
by V_{C C P D} = 3.3 V)
v (4)
v (6)
Level shifter Level shifter
required
required
Notes to Table 2–36:
(1) Input buffer is 3.3-V tolerant.
(2) The nCEO output buffer meets V_{O H} (MIN) = 2.4 V.
(3) Input buffer is 2.5-V tolerant.
(4) The nCEO output buffer meets V_OH (MIN) = 2.0 V.
(5) Input buffer is 1.8-V tolerant.
(6) An external 250-Ω pull-up resistor is not required, but recommended if signal levels on the board are not optimal.
For JTAG chains, the TDO pin of the first device drives the TDI pin of the
second device in the chain. The V_CCSEL input on the JTAG input I/O cells
(TCK, TMS, TDI, and TRST) is internally hardwired to GND selecting the
3.3-V/2.5-V input buffer powered by V_CCPD. The ideal case is to have the
V_CCIO of the TDO bank from the first device match the V_CCSEL settings for
TDI on the second device, but that may not be possible depending on the
application. Table 2–37 contains board design recommendations to
ensure proper JTAG chain operation.
Table 2–37. Supported TDO/TDI Voltage Combinations (Part 1 of 2)
Device
TDI Input
Buffer Power
Stratix II GX Always
V_{C C P D} (3.3 V)
Stratix II GX TDO V_{C C I O} Voltage Level in I/O Bank 4
V_{C C I O} = 3.3 V
v (1)
V_{C C I O} = 2.5 V
v (2)
V_{C C I O} = 1.8 V V_{C C I O} = 1.5 V V_{C C I O} = 1.2 V
v (3)
Level shifter Level shifter
required
required
Altera Corporation
October 2007
2–135
Stratix II GX Device Handbook, Volume 1