Specifications ispLSI 2128V

2

Functional Block Diagram

Figure 1. ispLSI 2128V Functional Block Diagram (128-I/O and 64-I/O Versions)

The 128-I/O 2128V contains 128 I/O cells, while the 64-

I/O version contains 64 I/O cells. Each I/O cell is directly

connected to an I/O pin and can be individually pro-

grammed to be a combinatorial input, output or

bi-directional I/O pin with 3-state control. The signal

levels are TTL compatible voltages and the output drivers

can source 4mA or sink 8mA. Each output can be

programmed independently for fast or slow output slew

rate to minimize overall output switching noise. Device

pins can be safely driven to 5V signal levels to support

mixed-voltage systems.

Eight GLBs, 32 or 16 I/O cells, two dedicated inputs and

two or one ORPs are connected together to make a

Megablock (see Figure 1). The outputs of the eight GLBs

are connected to a set of 32 or 16 universal I/O cells by

the two or one ORPs. Each ispLSI 2128V device contains

four Megablocks.

The GRP has as its inputs, the outputs from all of the

GLBs and all of the inputs from the bi-directional I/O cells.

All of these signals are made available to the inputs of the

GLBs. Delays through the GRP have been equalized to

minimize timing skew.

Clocks in the ispLSI 2128V device are selected using the

dedicated clock pins. Three dedicated clock pins (Y0, Y1,

Y2) or an asynchronous clock can be selected on a GLB

basis. The asynchronous or Product Term clock can be

generated in any GLB for its own clock.

Programmable Open-Drain Outputs

In addition to the standard output configuration, the

outputs of the ispLSI 2128V are individually program-

mable, either as a standard totem-pole output or an

open-drain output. The totem-pole output drives the

specified Voh and Vol levels, whereas the open-drain

output drives only the specified Vol. The Voh level on the

open-drain output depends on the external loading and

pull-up. This output configuration is controlled by a pro-

grammable fuse. When this fuse is erased (JEDEC “1”),

the output is configured as a totem-pole output. When

this fuse is programmed (JEDEC “0”), the output is

configured as an open-drain. The default configuration

when the device is in bulk erased state is totem-pole

configuration. The open-drain/totem-pole option is se-

lectable through the ispDesignEXPERT software tools.

Global

Routing

Pool

(GRP)

0139B/2128V

Megablock

RESET

Input Bus

D3

D2

D1

D0

D7

D6

D5

D4

Output Routing Pool (ORP)

Output Routing Pool (ORP)

C7

C6

C5

C4

C3

C2

C1

C0

IN 5

IN 4

I/O 91

I/O 90

I/O 89

I/O 88

I/O 87

I/O 86

I/O 85

I/O 84

I/O 83

I/O 82

I/O 81

I/O 80

I/O 79

I/O 78

I/O 77

I/O 76

I/O 75

I/O 74

I/O 73

I/O 72

I/O 71

I/O 70

I/O 69

I/O 68

I/O 67

I/O 66

I/O 65

I/O 64

I/O 95

I/O 94

I/O 93

I/O 92

Output Routing Pool (ORP)

Output Routing Pool (ORP)

Input Bus

B4

B5

B6

B7

B0

B1

B2

B3

A0

A1

A2

A3

A4

A5

A6

A7

ispEN

I/O 4

I/O 5

I/O 6

I/O 7

I/O 8

I/O 9

I/O 10

I/O 11

I/O 12

I/O 13

I/O 14

I/O 15

I/O 16

I/O 17

I/O 18

I/O 19

I/O 20

I/O 21

I/O 22

I/O 23

I/O 24

I/O 25

I/O 26

I/O 27

I/O 28

I/O 29

I/O 30

I/O 31

I/O 0

I/O 1

I/O 2

I/O 3

GOE 0

GOE 1

TDI/IN 0

TMS/IN 1

Generic Logic

Blocks (GLBs)

Global

Routing

Pool

(GRP)

0139B/2128V.64IO

Megablock

RESET

Input Bus

D3

D2

D1

D0

D7

D6

D5

D4

Output Routing Pool (ORP)

C7

C6

C5

C4

C3

C2

C1

C0

IN 5*

IN 4*

I/O 43

I/O 42

I/O 41

I/O 40

I/O 39

I/O 38

I/O 37

I/O 36

I/O 35

I/O 34

I/O 33

I/O 32

I/O 47

I/O 46

I/O 45

I/O 44

Output Routing Pool (ORP)

Input Bus

B4

B5

B6

B7

B0

B1

B2

B3

A0

A1

A2

A3

A4

A5

A6

A7

ispEN

I/O 4

I/O 5

I/O 6

I/O 7

I/O 8

I/O 9

I/O 10

I/O 11

I/O 12

I/O 13

I/O 14

I/O 15

I/O 0

I/O 1

I/O 2

I/O 3

GOE 0

GOE 1

TDI/IN 0

TMS/IN 1

*Not available on 84-PLCC Device

Generic Logic

Blocks (GLBs)