Electronic Components Datasheet Search |
|
ISPLSI81080V-60LB492 Datasheet(PDF) 4 Page - Lattice Semiconductor |
|
ISPLSI81080V-60LB492 Datasheet(HTML) 4 Page - Lattice Semiconductor |
4 / 26 page Specifications ispLSI 81080V 4 signals is selectable on an individual I/O cell basis. The I/O cell register can be programmed to operate as a D- type register or a D-type latch. The input thresholds are fixed at levels which comply with both 3.3V and 2.5V interfaces. The output driver can source 4mA and sink 8mA (3.3V output supply). The output drivers have a separate VCCIO power supply which is independent of the main VCC supply for the device. This feature allows the output drivers to run from either 3.3V or 2.5V while the device logic is always powered from 3.3V. The output drivers also provide individually programmable edge rates and open drain capability. A programmable pullup resistor is provided to tie off unused inputs and a programmable bus-hold latch is available to hold tristate outputs in their last valid state until the bus is driven again by another device. The ispLSI 8000V Family features 3.3V, non-volatile in- system programmability for both the logic and the interconnect structures, providing the means to develop truly reconfigurable systems. Programming is achieved through the industry standard IEEE 1149.1-compliant Boundary Scan interface using the JTAG protocol. Bound- ary Scan test is also supported through the same interface. An enhanced, multiple cell security scheme is provided that prevents reading of the JEDEC programming file when secured. After the device has been secured using this mechanism, the only way to clear the security is to execute a bulk-erase instruction. ispLSI 81080V Description The ispLSI 81080V device has nine Big Fast Megablocks for a total of 9 x 120 = 1080 macrocells. Each Big Fast Megablock has a total of 24 I/O cells and the Global Routing Plane has a total of 144 I/O cells. This gives (9 x 24) + 144 = 360 I/Os for the full I/O version, while the partial I/O version contains 72 Big Fast Megablock I/Os + 120 global I/Os = 192 I/Os. The total registers in the device is the sum of macrocells plus I/O cells, 1080 + 360 = 1440 registers. Embedded Tristate Bus There is a 108-line embedded internal tristate bus as part of the Global Routing Plane (GRP), enabling multiple GLBs to drive the same tracks. This bus can be parti- tioned into various bus widths such as twelve 9-line buses, six 18-line buses or three 36-line buses. The GLBs can dynamically share a subset of the Global Routing Plane tracks. This feature eliminates the need to convert tristate buses to wide multiplexers on the pro- grammable device. Up to 18 macrocells per GLB can participate in driving the embedded tristate bus. The remaining two macrocells per GLB are used to generate the internal tristate driver control signals on each data byte (with parity). The embedded tristate bus can also be configured as an extension of an external tristate bus using the bidirectional capability of the I/O cells con- nected to the Global Routing Plane. The Global Routing Plane I/Os 0-8 and 15-23 from each group (I/OGx as defined in the I/O Pin Location Table) can connect to the internal tristate bus as well as the unidirectional/non- tristate global routing channels. I/Os 9-14 connect only to the global routing channel. The embedded tristate bus has internal bus hold and arbitration features in order to make the function more “user friendly”. The bus hold feature keeps the internal bus at the previously driven logic state when the bus is not driven to eliminate bus float. The bus arbitration is performed on a “first come, first served” priority. In other words, once a logic block drives the bus, other logic blocks cannot drive the bus until the first releases the bus. This arbitration feature prevents internal bus contention when there is an overlap between two bus enable sig- nals. Typically, it takes about 3ns to resolve one bus signal coming off the bus to another bus signal driving the bus. The arbitration feature, combined with the predict- ability of the CPLD, makes the embedded tristate bus the most practical for real world bus implementation. ispLSI 8000V Family Description (Continued) |
Similar Part No. - ISPLSI81080V-60LB492 |
|
Similar Description - ISPLSI81080V-60LB492 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |