Lightspeed is continuing its efforts to bring the benefits of small feature
size processes to the designer without the costs associated with a full
cell-based ASIC design effort. The company is positioning its Modular Array
families as FPGA alternatives, particularly targeting Xilinx devices. Like
Virtex-II, I/Os in the new family can be set for a large number of different
signaling standards, has built-in JTAG, and supports the digitally
controlled impedance feature. Double data rate registers to support
high-speed external RAM are included in the I/O cells.
Lightspeed, with some 70 people, is already in production supplying
module-based ASICs. These are being made using 0.35-micron and 0.25-micron
processes. While the company would not divulge its current revenues, it did
state that nearly 200 customer designs have been completed. Approximately
one-half of these have resulted from the conversion of FPGA (primarily from
Xilinx) designs and the rest from ASIC designs.
With its latest release, the company is attempting to provide the benefits
of a 0.13-micron process at NREs that are a fraction of those for the
traditional ASIC approach. In the past, it has been doing this by using
modules, rather than gates, as the basic building blocks and interconnecting
these with only two layers of metal. The new 0.13-micron Luminance family will require three
metal layers to configure the logic within the modules and to provide the
required connectivity. AMI, with its XP line, and NEC, with its ISSP
family, also offer module-based ASICs that can be customized with a few
metal layers.
The module approach permits the company to stock wafers that only need the
final three metal layers, significantly shortening the time required to
deliver the first devices. NRE charges will be about $250K, one-third to
one-quarter of those for a traditional 0.13-micron cell-based ASIC.
In addition to the lower NRE charges, short turn around times for first
silicon, and a simplified design flow, Lightspeed does not require the user
to provide test vectors. The company uses proprietary built-in test
circuitry and boundary scan logic that enables it to generate the required
test vectors with 100% stuck-at-fault test coverage.
The Luminance family is being produced on TSMC's 0.13-micron, 8-layer
copper process using its1.0V HS (high-speed) logic process. Luminance
parts run at a core voltage of 1.2V and have the capability to set I/O
signal voltages at levels up to 3.3V. The company claims that the
performance of designs in the new devices will be comparable to 0.15-micron
designs. The 700 MHz claim is based on 10 levels of logic. Lightspeed
expects that most the Luminance designs will be for performance levels that
are less than one-half of the 700 MHz claim.
Lightspeed has received a 0.13-micron test chip that was produce using
TSMC's CyberShuttle program. The company is now accepting customer designs
and expects to be able to start production deliveries during 1Q03. It will
be banking eight-inch wafers for rapid customer delivery.
The company has not yet completely defined the Luminance family, but it will
probably contain 6 or 7 parts with different amounts of user configurable
logic and embedded memory. It is expected that the family will extend to 10
million usable ASIC gates with 5 Mbits of dual-port embedded memory.
Lightspeed expects the family to be most attractive to those customers
needing several 100K production parts.
Luminance has been designed to function as a replacement for Xilinx's
Virtex-II family as well as a low NRE cost ASIC. The I/Os can be configured
to support a wide variety of signaling standards. LVDS and LVPECL speeds of
1.244 Gbps can be achieved. These speeds are significantly higher than
those that can be obtained with Virtex-II. Also, Luminance will contain 16
separate I/O banks versus 8 for Virtex. Like Virtex, the I/O's impedance
can be digitally controlled.
Lightspeed plans on adding 3.125 Gbps SERDES with an optional 8B/10B
encode/decode function to selected members of the family during 2003. This
addition is to make the Luminance devices suitable for converting Virtex-II
Pro designs that use the SERDES feature.