Lead-
Free
Package
Options
Available!
ispGDX 240VA
In-System Programmable
3.3V Generic Digital Crosspoint
Functional Block Diagram
I/O Pins D
ISP
Control
®
Features
• IN-SYSTEM PROGRAMMABLE GENERIC DIGITAL
CROSSPOINT FAMILY
— 240 I/O, “Any Input to Any Output” Routing
— Advanced Architecture Addresses Programmable
PCB Interconnect, Bus Interface Integration and
Jumper/Switch Replacement
— Fixed HIGH or LOW Output Option for Jumper/DIP
Switch Emulation
— Space-Saving Fine Pitch BGA Packaging
— Dedicated IEEE 1149.1-Compliant Boundary Scan
Test
• HIGH PERFORMANCE E
2
CMOS
®
TECHNOLOGY
— 3.3V Core Power Supply
— 4.5ns Input-to-Output/4.0ns Clock-to-Output Delay
— 200MHz Maximum Clock Frequency
— TTL/3.3V/2.5V Compatible Input Thresholds and
Output Levels (Individually Programmable)
— Low-Power: 20.0mA Quiescent Icc
— 24mA I
OL
Drive with Programmable Slew Rate
Control Option
— PCI Compatible Drive Capability
— Schmitt Trigger Inputs for Noise Immunity
— Electrically Erasable and Reprogrammable
— Non-Volatile E
2
CMOS Technology
• ispGDXVA OFFERS THE FOLLOWING ADVANTAGES
— 3.3V In-System Programmable Using Boundary Scan
Test Access Port (TAP)
— Change Interconnects in Seconds
• FLEXIBLE ARCHITECTURE
— Combinatorial/Latched/Registered Inputs or Outputs
— Individual I/O Tri-state Control with Polarity Control
— Dedicated Clock/Clock Enable Input Pins (four) or
Programmable Clocks/Clock Enables from I/O Pins (60)
— Single Level 4:1 Dynamic Path Selection (Tpd = 4.5ns)
— Programmable Wide-MUX Cascade Feature
Supports up to 16:1 MUX
— Programmable Pull-ups, Bus Hold Latch and Open
Drain on I/O Pins
— Outputs Tri-state During Power-up (“Live Insertion”
Friendly)
• LEAD-FREE PACKAGE OPTIONS
I/O Pins C
I/O Pins A
I/O
Cells
Global Routing
Pool
(GRP)
I/O
Cells
Boundary
Scan
Control
I/O Pins B
Description
The ispGDXVA architecture provides a family of fast,
flexible programmable devices to address a variety of
system-level digital signal routing and interface require-
ments including:
• Multi-Port Multiprocessor Interfaces
• Wide Data and Address Bus Multiplexing
(e.g. 16:1 High-Speed Bus MUX)
• Programmable Control Signal Routing
(e.g. Interrupts, DMAREQs, etc.)
• Board-Level PCB Signal Routing for Prototyping or
Programmable Bus Interfaces
The ispGDX240VA device features fast operation, with
input-to-output signal delays (Tpd) of 4.5ns and clock-to-
output delays of 4.0ns.
The architecture of the devices consists of a series of
programmable I/O cells interconnected by a Global Rout-
ing Pool (GRP). All I/O pin inputs enter the GRP directly
or are registered or latched so they can be routed to the
required I/O outputs. I/O pin inputs are defined as four
sets (A,B,C,D) which have access to the four MUX inputs
Copyright © 2004 Lattice Semiconductor Corporation. All brand or product names are trademarks or registered trademarks of their respective holders. The specifications and information herein
are subject to change without notice.
LATTICE SEMICONDUCTOR CORP., 5555 Northeast Moore Ct., Hillsboro, Oregon 97124, U.S.A.
Tel. (503) 268-8000; 1-800-LATTICE; FAX (503) 268-8556; http://www.latticesemi.com
August 2004
gdx240va_06
1
Specifications
ispGDX240VA
Description (Continued)
found in each I/O cell. Each output has individual, pro-
grammable I/O tri-state control (OE), output latch clock
(CLK), clock enable (CLKEN), and two multiplexer con-
trol (MUX0 and MUX1) inputs. Polarity for these signals
is programmable for each I/O cell. The MUX0 and MUX1
inputs control a fast 4:1 MUX, allowing dynamic selection
of up to four signal sources for a given output. A wider
16:1 MUX can be implemented with the MUX expander
feature of each I/O and a propagation delay increase of
2.0ns. OE, CLK, CLKEN, and MUX0 and MUX1 inputs
can be driven directly from selected sets of I/O pins.
Optional dedicated clock input pins give minimum clock-
to-output delays. CLK and CLKEN share the same set of
I/O pins. CLKEN disables the register clock when
CLKEN = 0.
Through in-system programming, connections between
I/O pins and architectural features (latched or registered
inputs or outputs, output enable control, etc.) can be
defined. In keeping with its data path application focus,
the ispGDXVA devices contain no programmable logic
arrays. All input pins include Schmitt trigger buffers for
noise immunity. These connections are programmed
into the device using non-volatile E
2
CMOS technology.
Non-volatile technology means the device configuration
is saved even when the power is removed from the
device.
Table 1. ispGDXVA Family Members
ispGDXV/VA Device
ispGDX80VA
I/O Pins
I/O-OE Inputs*
I/O-CLK / CLKEN Inputs*
I/O-MUXsel1 Inputs*
I/O-MUXsel2 Inputs*
Dedicated Clock Pins**
EPEN
TOE
BSCAN Interface
RESET
Pin Count/Package
80
20
20
20
20
2
1
1
4
1
100-Pin TQFP
ispGDX160V/VA
160
40
40
40
40
4
1
1
4
1
ispGDX240VA
240
60
60
60
60
4
1
1
4
1
In addition, there are no pin-to-pin routing constraints for
1:1 or 1:n signal routing. That is,
any
I/O pin configured
as an input can drive one or more I/O pins configured as
outputs.
The device pins also have the ability to set outputs to
fixed HIGH or LOW logic levels (Jumper or DIP Switch
mode). Device outputs are specified for 24mA sink and
12mA source current (at JEDEC LVTTL levels) and can
be tied together in parallel for greater drive. On the
ispGDXVA, each I/O pin is individually programmable for
3.3V or 2.5V output levels as described later. Program-
mable output slew rate control can be defined
independently for each I/O pin to reduce overall ground
bounce and switching noise.
All I/O pins are equipped with IEEE1149.1-compliant
Boundary Scan Test circuitry for enhanced testability. In
addition, in-system programming is supported through
the Test Access Port via a special set of private com-
mands.
The ispGDXVA I/Os are designed to withstand “live
insertion” system environments. The I/O buffers are
disabled during power-up and power-down cycles. When
designing for “live insertion,” absolute maximum rating
conditions for the Vcc and I/O pins must still be met.
208-Pin PQFP 388-Ball fpBGA
208-Ball fpBGA
272-Ball BGA
* The CLK/CLK_EN, OE, MUX0 and MUX1 terminals on each I/O cell can each be assigned to
25% of the I/Os.
** Global clock pins Y0, Y1, Y2 and Y3 are multiplexed with CLKEN0, CLKEN1, CLKEN2 and
CLKEN3 respectively in all devices.
2
Specifications
ispGDX240VA
Architecture
The ispGDXVA architecture is different from traditional
PLD architectures, in keeping with its unique application
focus. The block diagram is shown below. The program-
mable interconnect consists of a single Global Routing
Pool (GRP). Unlike ispLSI
®
devices, there are no pro-
grammable logic arrays on the device. Control signals for
OEs, Clocks/Clock Enables and MUX Controls must
come from designated sets of I/O pins. The polarity of
these signals can be independently programmed in each
I/O cell.
Each I/O cell drives a unique pin. The OE control for each
I/O pin is independent and may be driven via the GRP by
one of the designated I/O pins (I/O-OE set). The I/O-OE
set consists of 25% of the total I/O pins. Boundary Scan
test is supported by dedicated registers at each I/O pin.
In-system programming is accomplished through the
standard Boundary Scan protocol.
The various I/O pin sets are also shown in the block
diagram below. The A, B, C, and D I/O pins are grouped
together with one group per side.
I/O Architecture
Each I/O cell contains a 4:1 dynamic MUX controlled by
two select lines as well as a 4x4 crossbar switch con-
trolled by software for increased routing flexiability (Figure
1). The four data inputs to the MUX (called M0, M1, M2,
and M3) come from I/O signals in the GRP and/or
adjacent I/O cells. Each MUX data input can access one
quarter of the total I/Os. For example, in a 240-I/O
ispGDXVA, each data input can connect to one of 60 I/O
pins. MUX0 and MUX1 can be driven by designated I/O
pins called MUXsel1 and MUXsel2. Each MUXsel input
covers 25% of the total I/O pins (e.g. 60 out of 240). MUX0
and MUX1 can be driven from either MUXsel1 or MUXsel2.
Figure 1. ispGDXVA I/O Cell and GRP Detail (240 I/O Device)
Logic “0” Logic “1”
240 I/O Inputs
I/OCell 0
I/O Cell 239
I/O Cell 1
I/O Cell 238
E
2
CMOS
Programmable
Interconnect
From MUX Outputs
of 2 Adjacent I/O Cells
N+2
I/O Group A
I/O Group B
I/O Group C
I/O Group D
N+1
4x4
Crossbar
Switch
•
•
•
To 2 Adjacent
I/O Cells above
Bypass Option
Register
or Latch
4-to-1 MUX
M0
M1
M2
M3
MUX0 MUX1
To 2 Adjacent
I/O Cells below
Prog.
Prog.
Pull-up
Bus Hold
Latch
(VCCIO)
A
B
D
CLK
CLK_EN Reset
C
R
Prog. Open Drain
2.5V/3.3V Output
Prog. Slew Rate
I/O
Pin
Q
N-1
N-2
•
•
•
•
•
•
From MUX Outputs
of 2 Adjacent I/O Cells
Boundary
Scan Cell
I/O Cell N
•
•
•
I/O Cell 118
••••••
I/O Cell 121
I/O Cell 119
120 I/O Cells
240 Input GRP
Inputs Vertical
Outputs Horizontal
Y0-Y3
Global
Clocks /
Clock_Enables
Global
Reset
I/O Cell 120
120 I/O Cells
ispGDXVA architecture enhancements over ispGDX (5V)
3
Specifications
ispGDX240VA
I/O MUX Operation
MUX1
0
0
1
1
MUX0
0
1
1
0
Data Input Selected
M0
M1
M2
M3
allow adjacent I/O cell outputs to be directly connected
without passing through the global routing pool. The
relationship between the [N+i] adjacent cells and A, B, C
and D inputs will vary depending on where the I/O cell is
located on the physical die. The I/O cells can be grouped
into “normal” and “reflected” I/O cells or I/O “hemi-
spheres.” These are defined as:
Device
ispGDX80VA
Normal I/O Cells
TBA
Reflected I/O Cells
TBA
B20-B39, C0-C19,
C20-C39, D0-D19
TBA
Flexible mapping of MUXsel
x
to MUX
x
allows the user to
change the MUX select assignment after the ispGDXVA
device has been soldered to the board. Figure 1 shows
that the I/O cell can accept (by programming the appro-
priate fuses) inputs from the MUX outputs of four adjacent
I/O cells, two above and two below. This enables cascad-
ing of the MUXes to enable wider (up to 16:1) MUX
implementations.
The I/O cell also includes a programmable flow-through
latch or register that can be placed in the input or output
path and bypassed for combinatorial outputs. As shown
in Figure 1, when the input control MUX of the register/
latch selects the “A” path, the register/latch gets its inputs
from the 4:1 MUX and drives the I/O output. When
selecting the “B” path, the register/latch is directly driven
by the I/O input while its output feeds the GRP. The
programmable polarity Clock to the latch or register can
be connected to any I/O in the I/O-CLK/CLKEN set (one-
quarter of total I/Os) or to one of the dedicated clock input
pins (Y
x
). The programmable polarity Clock Enable input
to the register can be programmed to connect to any of
the I/O-CLK/CLKEN input pin set or to the global clock
enable inputs (CLKEN
x
). Use of the dedicated clock
inputs gives minimum clock-to-output delays and mini-
mizes delay variation with fanout. Combinatorial output
mode may be implemented by a dedicated architecture
bit and bypass MUX. I/O cell output polarity can be
programmed as active high or active low.
ispGDX160V/VA B19-B0, A39-A20,
A19-A0, D39-D20
ispGDX240VA
TBA
Table 2 shows the relationship between adjacent I/O
cells as well as their relationship to direct MUX inputs.
Note that the MUX expansion is circular and that I/O cell
B30, for example, draws on I/Os B29 and B28, as well as
B31 and B32, even though they are in different hemi-
spheres of the physical die. Table 2 shows some typical
cases and all boundary cases. All other cells can be
extrapolated from the pattern shown in the table.
Figure 2. I/O Hemisphere Configuration of
ispGDX240VA
I/O cell 0
I/O cell 239
D59
A0
I/O cell index increases in this direction
D30
D29
D0
C59
I/O cell index increases in this direction
MUX Expander Using Adjacent I/O Cells
The ispGDXVA allows adjacent I/O cell MUXes to be
cascaded to form wider input MUXes (up to 16 x 1)
without incurring an additional full Tpd penalty. However,
there are certain dependencies on the locality of the
adjacent MUXes when used along with direct MUX
inputs.
Adjacent I/O Cells
Expansion inputs MUXOUT[n-2], MUXOUT[n-1],
MUXOUT[n+1], and MUXOUT[n+2] are fuse-selectable
for each I/O cell MUX. These expansion inputs share the
same path as the standard A, B, C and D MUX inputs, and
Direct and Expander Input Routing
Table 2 also illustrates the routing of MUX direct inputs
that are accessible when using adjacent I/O cells as
inputs. Take I/O cell D33 as an example, which is also
shown in Figure 3.
A59
B0
B29
B30
B59
I/O cell 119 I/O cell 120
4
C0
Specifications
ispGDX240VA
Figure 3. Adjacent I/O Cells vs. Direct Input Path for
ispGDX240VA, I/O D33
ispGDX240VA I/O Cell
I/O Group A
D31 MUX Out
I/O Group B
D32 MUX Out
I/O Group C
D34 MUX Out
I/O Group D
D35 MUX Out
4x4
Crossbar
Switch
S1 S0
.m0
.m1
.m2
.m3
Special Features
Slew Rate Control
All output buffers contain a programmable slew rate
control that provides software-selectable slew rate op-
tions.
Open Drain Control
D33
It can be seen from Figure 3 that if the D31 adjacent I/O
cell is used, the I/O group “A” input is no longer available
as a direct MUX input.
The ispGDXVA can implement MUXes up to 16 bits wide
in a single level of logic, but care must be taken when
combining adjacent I/O cell outputs with direct MUX
inputs. Any particular combination of adjacent I/O cells as
MUX inputs will dictate what I/O groups (A, B, C or D) can
be routed to the remaining inputs. By properly choosing
the adjacent I/O cells, all of the MUX inputs can be
utilized.
Table 2. Adjacent I/O Cells (Mapping of
ispGDX240VA)
Data A/ Data B/ Data C/ Data D/
MUXOUT MUXOUT MUXOUT MUXOUT
B30
B31
B32
Reflected
I/O Cells
B33
D26
D27
D28
D29
D30
D31
D32
Normal
I/O Cells
D33
B26
B27
B28
B29
B32
B33
B34
B35
D28
D29
D30
D31
D28
D29
D30
D31
B24
B25
B26
B27
B31
B32
B33
B34
D27
D28
D29
D30
D29
D30
D31
D32
B25
B26
B27
B28
B29
B30
B31
B32
D25
D26
D27
D28
D31
D32
D33
D34
B27
B28
B29
B30
B28
B29
B30
B31
D24
D25
D26
D27
D32
D33
D34
D35
B28
B29
B30
B31
All output buffers provide a programmable Open-Drain
option which allows the user to drive system level reset,
interrupt and enable/disable lines directly without the
need for an off-chip Open-Drain or Open-Collector buffer.
Wire-OR logic functions can be performed at the printed
circuit board level.
Pull-up Resistor
All pins have a programmable active pull-up. A typical
resistor value for the pull-up ranges from 50kΩ to 80kΩ.
Output Latch (Bus Hold)
All pins have a programmable circuit that weakly holds
the previously driven state when all drivers connected to
the pin (including the pin's output driver as well as any
other devices connected to the pin by external bus) are
tristated.
User-Programmable I/Os
The ispGDX240VA features user-programmable
I/Os supporting either 3.3V or 2.5V output voltage level
options. The ispGDX240VA uses a VCCIO pin to provide
the 2.5V reference voltage when used.
PCI Compatible Drive Capability
The ispGDX240VA supports PCI compatible drive capa-
bility for all I/Os.
5
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