TMS380SRA_技术文档

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SPWS006 − NOVEMBER 1991

FN PACKAGE

(TOP VIEW)

• Source-Routing Bridge Accelerator for

16-Mbps and 4-Mbps Token-Ring Bridges

• Compatible With the IBM Token-Ring

Network Architecture

• Interfaces Directly to the TMS380Cx6

Second-Generation Network

Commprocessor

6

5

4

3

2 1 44 43 42 41 40

†

MAXPH

MADH0

MADH1

MADH2

MADH3

GND

7

39 NC

8

38

37

36

35

34

33

32

31

30

29

NC

• Provides Automatic Recognition of

Source-Routing Field in Token-Ring Frame

for Hardware-Accelerated-Frame Copying

and High-Performance Bridging

9

10

11

12

13

14

15

16

17

V

CC

GND

• Utilizes TI-Patented Enhanced-Address

Copy Option (EACO) Interface of the

TMS380Cx6

†

V

NC

CC

†

MADH4

MADH5

MADH6

MADH7

NC

†

NC

• High-Performance, 1-µm EPIC CMOS

†

NC

Technology

XFAIL

18 19 20 21 22 23 24 25 26 27 28

• 44-Pin JEDEC PLCC Surface-Mount

Package

†

These pins must be left externally unconnected.

NC − No internal connection

Token-Ring LAN SRA Applications Diagram

Token-Ring Adapter

Transmit

Receive

To

Network

TMS380Cx6

TMS38054

Attached

System

Bus

TMS380SRA

Memory

EPIC is a trademark of Texas Instruments Incorporated.

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Copyright  1991, Texas Instruments Incorporated

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1

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SPWS006 − NOVEMBER 1991

description

The TMS380SRA source-routing accelerator (SRA) device provides the hardware for direct recognition and

parsing of the source-routing field in a token-ring frame. The TMS380SRA is designed to interface directly to

the TMS380Cx6. The TMS380SRA searches the received frame for frames that need to be forwarded to the

adjacent ring by examining the source-routing field. If a frame is to be forwarded, the frame is copied by the

adapter and transferred to the attached system through the system interface of the TMS380Cx6. A second

adapter with the TMS380SRA can also be included in the attached system (thus forming a bridge) to provide

an identical function for the second ring. Transfer of data between the two rings (bridging) occurs under attached

system-software control.

A block diagram of the TMS380SRA is shown in Figure 1. The internal registers fall into two categories: registers

that can be set by the host software for the specific bridge parameters for this adapter, and dynamic registers

that are loaded with the received frames-routing information as read from the adapter bus transfer. The routing

information is compared to the specified bridge parameters, which determines the value to be placed on the

XMATCH and XFAIL pins. The memory-interface (MIF) address output during memory cycles is shown in

Table 1. Status information is provided on the MADH0−MADH7 signals in the second quarter of the memory

cycle (shaded area). MADH6 and MADH7 are the bits that can be used by an EACO device. The information

provided in these bits during the second quarter of the memory cycle can be decoded as follows:

MADH6

H

=

The TMS380Cx6 PH RX DMA machine is transferring a word of received

frame data to memory.

L

=

At all other times

MADH7

H

The TMS380Cx6s PH RX DMA machine is transferring the first word of a

new received frame to memory. In a token-ring frame, the first word contains

the AC and FC fields.

L

=

At all other times

The decode of the rest of the status information is shown in Table 2 and Table 3.

The TMS380SRA is available in a 44-lead plastic chip-carrier package (FN suffix) and is characterized for

operation from 0°C to 70°C (L suffix). The electrostatic-discharge protection of the TMS380SRA is rated at

500 V human-body model (HBM).

MBCLK1

MBCLK2

MRESET

MDDIR

Registers

Containing:

XMATCH

XFAIL

XMATCH

XFAIL

Control

SET.BRIDGE.PARMS

Command Parameters

− Source Ring

MBEN

Compare

State

− Target Ring

Machine

− Bridge Number

− Options

MAXPH

MAXPL

MADH(0 − 7)

MADL(0 − 7)

18

2

Dynamic Storage

− Bus Status Byte

− Routing-Information

Field Data

Frame

Start

V

CC

Control

GND

4

Figure 1. TMS380SRA Block Diagram

2

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SPWS006 − NOVEMBER 1991

Table 1. TMS380Cx6 Address Output During Memory Cycle

FIRST QUARTER

SECOND QUARTER

REST OF CYCLE

A12

†

MAX0

AX0

AX1

AX2

AX3

AX4

A0

A12

AX0

A14

MAXPH

Parity

A14

†

MAX2

MAXPL

MADH0

MADH1

MADH2

MADH3

MADH4

MADH5

MADH6

MADH7

MADL0

MADL1

MADL2

MADL3

MADL4

MADL5

MADL6

MADL7

MROMEN

AX2

Status

AX4

A0

Parity

Data

A1

Data

A2

Data

A3

Data

A4

Data

A5

Data

A6

Data

A7

Data

A8

Data

A9

A1

Data

A10

A11

A12

A13

A14

ROMEN

A2

Data

A3

Data

A4

Data

A5

Data

A6

Data

†

A13

†

These signals do not attach to the TMS380SRA; therefore, there are no corresponding pins.

Table 2. Status Information on MADH0−MADH7

SECOND-QUARTER MEMORY CYCLE

FUNCTION

‡

Code/data

MADH0

MADH1

MADH2

Indicates which internal module of the TMS380Cx6 has ownership of the

adapter memory bus (see Table 3) .

‡

MADH3

MADH4

MADH5

SIF DMA active

PH RX DMA cycle

New RX frame

MADH6

MADH7

‡

To the TMS380SRA, these bits are don’t care.

3

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SPWS006 − NOVEMBER 1991

Table 3. Decode of Status Information on MADH1−MADH4

MADH1

MADH2

MADH3

MADH4

REPRESENTATION

DRAM controller

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Not assigned

PH TX DMA machine

PH RX DMA machine

PH TX buffer manager

PH RX buffer manager

SIF DIO machine

SIF DMA machine

CP (uses bus)

CP (does not use bus)

Not assigned

Program debug controller

No memory access

†

To the TMS380SRA, these bits are don’t care.

Pin Functions

‡

I/O/Z

PIN NAME

NO.

DESCRIPTION

MADHO

MADH1

MADH2

MADH3

MADH4

MADH5

MADH6

MADH7

8

9

Adapter-memory address, data and status bus − high byte. For the first quarter of the adapter-

memory cycle, these bus lines carry address bits AX4 and A0 to A6; for the second quarter, they carry

status bits; and for the third and fourth quarters, they carry data bits 0 to 7. The most significant bit

is MADH0 and the least significant bit is MADH7.

10

11

14

15

16

17

I/O

Memory Cycle

1Q

2Q

3Q

4Q

AX4, A0 − A6

Status

D0 − D7

Signal

MADLO

MADL1

MADL2

MADL3

MADL4

MADL5

MADL6

MADL7

41

42

43

44

2

3

4

5

Adapter-memory address, data and status bus − low byte. For the first quarter of the adapter-memory

cycle these bus lines carry address bits A7 to A14; for the second quarter, they carry address bits

AX4 and A0 to A6; and for the third and fourth quarters, they carry data bits 8 to 15. The most

significant bit is MADL0 and the least significant bit is MADL7.

I/O

Memory Cycle

1Q

2Q

3Q

4Q

AX7 − A14

AX4, A0 − A6

D8 − D15

Signal

Adapter-memory-extended address and parity − high byte. For the first quarter of a memory cycle,

carries the extended address bit (AX1); for the second quarter of a memory cycle, it carries the

extended address bit (AX)); and for the last half of the memory cycle, it carries the parity bit for the

high data byte.

MAXPH

7

I/O

Memory Cycle

1Q

2Q

3Q

4Q

AX1

AX0

Parity

Signal

Adapter-memory-extended address parity − low byte. For the first quarter of the adapter memory

cycle, MAXPL carries the extended address bit (AX3), for the second quarter of a memory cycle, it

carries extended address bit (AX2); and for the last half of the memory cycle, it carries the parity bit

for the low data byte.

MAXPL

6

Memory Cycle

1Q

2Q

3Q

4Q

AX3

AX2

Parity

Signal

Denotes input/output/high-impedance state

‡

4

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SPWS006 − NOVEMBER 1991

Pin Functions (Continued)

†

I/O/Z

PIN NAME

NO.

DESCRIPTION

Adapter-bus clock 1 and adapter-bus clock 2. MBCLK1 and MBCLK2 are references for all

adapter-bus transfers. MBCLK2 lags MBCLK1 by a quarter of a cycle. These clocks operate at 8 MHz

for a 64-MHz OSCIN (on the TMS380Cx6) and 6 MHz for a 48-MHz OSCIN (on the TMS380Cx6),

which is twice the memory cycle rate. The MBCLK signals are always a divide-by-8 of the OSCIN (on

the TMS380Cx6) frequency.

MBCLK1

MBCLK2

24

22

I

Buffer enable. MBEN enables the bidirectional buffer outputs on the MADH, MAXPH, MAXPL, and

MADL buses during the data phase. MBEN is used in conjunction with MDDIR, which selects the

buffer output direction.

I

19

20

21

MBEN

(see Note 1)

H = Buffer output disabled

L

= Buffer output enabled

Data direction. MDDIR is used as a direction control for the bidirectional bus drivers from the

TMS380Cx6. MDDIR becomes valid before MBEN becomes active.

I

MDDIR

MRESET

H = TMS380Cx6 memory-bus write

L

= TMS380Cx6 memory-bus read

Memory bus reset. MRESET is a reset signal generated when either the ARESET bit in the SIFACL

register is set or the SRESET is asserted. This signal is used for resetting external adapter bus glue

logic and the TMS380SRA.

I

(see Note 1)

H = External logic not reset

L

= External logic reset

External fail-to-match. The TMS380SRA device uses XFAIL to indicate to the TMS380Cx6 that it

should not copy the data frame nor set the ARI/FCI bits due to an external address match. The

ARI/FCI bits may still be set by the TMS380Cx6 due to an internal address match (see table in

XMATCH description).

XFAIL

29

O

H = No address match by TMS380SRA

L

= TMS380SRA armed state

External match. The TMS380SRA device uses XMATCH to indicate to the TMS380Cx6 to copy the

data frame and set the ARI/FCI bits.

H = Address match recognized by TMS380SRA

L

= TMS380SRA armed state

XMATCH

XFAIL

Function

XMATCH

28

O

0

1

0

1

0

Armed (processing frame data)

Do not externally match the frame

Copy the frame

1

Hi-Z

1

Hi-Z

Do not externally match the frame

Reset state (TMS380SRA is in the reset state

V

(2 pins)

13,35

5-V supply voltage

Ground

CC

GND (4 pins)

NC (13 pins)

1,12,23,34

These pins must be unconnected.

†

Denotes input/output/high-impedance state

NOTE 1: Pin has an internal pullup device to maintain a high voltage level when left unconnected (no etch or loads)

operation

The TMS380SRA is designed to be interfaced with the TMS380Cx6 on DRAM-based adapters operating at

4-MHz adapter-bus speed with no external glue logic required. In adapter designs utilizing EPROMs or other

devices in addition to DRAMs and a BIA PROM, it may be necessary to buffer the DRAMs in order to reduce

the total bus loading below the maximum output load capacitance (50 pF) of the TMS380SRA.

The TMS380SRA control registers are mapped into the TMS380Cx6 memory map at all times, and no external

chip-select signal is used. The adapter software controls access to these registers through the

SET.BRIDGE.PARMS command (>0010), as described in the TMS380 Second-Generation Token-Ring User’s

Guide (SPWS005).

5

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SPWS006 − NOVEMBER 1991

operation (continued)

The TMS380SRA is reset by a low-level signal on MRESET. The TMS380Cx6 forces a MRESET active during

a hardware or software reset of the adapter. In the reset state of the TMS380SRA, XMATCH and XFAIL are in

the high-impedance state.

The TMS380SRA is also reset by the SET.BRIDGE.PARMS command before loading the supplied values and

conditions for the TMS380SRA to use. If the SET.BRIDGE.PARMS command is supplied with invalid values,

the values are not loaded and the device remains in the reset state (disabled).

The TMS380SRA should be placed such that the length of the signal lines between it and the TMS380Cx6 does

not exceed 7 cm in length. Figure 2 illustrates the TMS380Cx6 to TMS380SRA interface.

TMS380Cx6

TMS380SRA

MBCLK1

MBCLK2

MRESET

MAXPH

MBCLK1

MBCLK2

MRESET

MAXPH

MAXPL

MADH(0 − 7)

MADL(0 − 7)

MBEN

MADH(0 − 7)

MADL(0 − 7)

MBEN

MDDIR

XMATCH

XFAIL

XMATCH

XFAIL

Figure 2. TMS380Cx6 to TMS380SRA Interface

bridging

Bridging is the process of passing information from one physical ring to another and is achieved by having a

token-ring adapter attached to each ring but sharing a common attached-system processor. Each adapter

monitors frames received on its ring for frames to be forwarded via its colleague to the other ring. When such

a frame is detected, the transfer takes place via the attached-system processor. Each of these bridge adapters

has a designator composed of its own ring number and its individual bridge number, and each also knows the

ring number and bridge number of its colleague. This principle of the bridge is illustrated in Figure 3. Bridge #3

on ring 1 looks for frames to be forwarded to ring 2, and similarly bridge #3 on ring 2 looks for frames to forward

to ring 1.

Bridge #3

Token-Ring Adapter

Ring

2

Ring

1

TMS38054

TMS380Cx6

TMS38054

TMS380SRA

Attached-

System

Bus

Memory

Figure 3. SRA Bridge

6

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ꢒ ꢒ

SPWS006 − NOVEMBER 1991

bridging (continued)

The TMS380SRA source-routing accelerator provides for high-speed frame copying and forwarding to the

attached system. The SRA monitors incoming frames and asserts either XMATCH and XFAIL for each frame

to indicate whether the frame should be bridged. Asserting XMATCH enables the TMS380Cx6 commprocessor

to copy the frame, set the address recognize indicator (ARI) bits in the frame status (FS) byte, and set frame

copied indicator (FCI) bits in the FS if the frame is copied. The attached system provides the appropriate frame

building and forwarding services as well as the bridge-control functions described in the IBM token-ring network

architecture reference.

The frame format containing the routing information is shown in Figure 4. The most significant bit of the

source-address field is transmitted as a one, indicating that the frame contains routing information. If this bit is

zero, the TMS380SRA does not copy the frame. The routing-information field immediately follows the source

address and contains a 2-byte routing-control field and additional 2-byte route designators. The TMS380SRA

supports up to fifteen route designators (see Note). The frame data, CRC field, end deliminator, and frame status

follow the routing-information field.

Most Significant Bit (MSb) of Source Address = 1

Destination

Address

Source

Address

Routing

Information

PCF

2

Data

CRC

4

EDEL

1

FS

1

SDEL

1

6

2-32

Number of Bytes

Figure 4. Frame Format Containing Routine Information

NOTE: IBM’s current token-ring source-routing architecture supports only an 18-byte routing-information field. Texas Instruments Release

1.00, 2.00 and 2.10 second-generation adapter software will not transmit frames with routing-information fields longer than 18 bytes.

The routing-information field is expanded in Figure 5. If the frame is routed via a particular sequence of bridges

(i.e., nonbroadcast), all the required route designators are provided by the token-ring node sourcing the frame.

If the frame is a broadcast and meets requirements for forwarding (as determined by the routing-control field),

the TMS380SRA copies the frame and the attached system adds the route designator of the next ring to the

end of the routing-information field and transmits the frame through the colleague adapter.

Routing

Control

Route

Designator

Designator Designator

2 Bytes

Up to 15 Route Designators

Figure 5. Routing-Information Field

7

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ꢒ

SPWS006 − NOVEMBER 1991

bridging (continued)

The routing-control field contains two bytes of information as shown in Figure 6. Bits 0−2 indicate if the frame

is a broadcast, and if so, what type. Bits 3−7 are the length field and indicate the length of the routing-information

field, including the routing-control field. Bit 8 is a direction bit that, for nonbroadcast frames, indicates the order

in which route designators should be interpreted by bridges routing the frame. Bits 9−11 are the largest

frame-indicator bits, which can be modified by the attached system to indicate the maximum frame size that can

travel via that bridge. The TMS380SRA ignores bit 2 in the broadcast-indicator field, bits 9−11 in the largest

frame size field, and bits 12−15 in the reserved field.

Bit

0

1

2

3

4

5

6

7

8

9

10 11 12 13 14 15

Broadcast

Indicators

Length of

Routing Information

Largest

Frame Size

DIR

Reserved

These Bits Ignored by SRA

Figure 6. Routing-Control Field

Each ring in a multiple-ring network is assigned a unique ring number, and each bridge is assigned a bridge

number, which may or may not be unique. Together the ring and bridge number form a route designator as shown

in Figure 7. The two bytes of the route designator are divided into two parts. The least significant K-bits are the

individual bridge number, and the most significant K-bits are the ring number. The individual bridge-number

portion allows parallel bridges to exist to share traffic between two particular rings. The value of K is set using

the PARTITION_LENGTH parameter of the SET.BRIDGE.PARMS command.

Ring Number

Individual Bridge #

16-K Bits

K Bits

Figure 7. Route-Designator Field

frame-copying algorithm

Frame copying by the TMS380SRA is controlled by register-bit settings in the TMS380SRA and the

incoming-frame routing-information field. If a frame is to be copied, the TMS380SRA asserts XMATCH,

otherwise XFAIL is asserted. The TMS380SRA copies only frames with the source-routing-indicator bit set in

the source address. The major parsing function is controlled by the broadcast bit settings of the incoming frame

in the routing-control field [the broadcast indicator bits of the routing-control field (bits 0−2)]. The frame-copy

algorithms are as follows:

0xx — Indicates that the routing-information field contains a specific route for the frame to travel through the

network (nonbroadcast routing). For direction bit equal zero, the TMS380SRA examines the route designators

for two adjacent designators containing its own adapter ring number and bridge number, and its colleague

adapter’s ring number. For direction bit equal one, the TMS380SRA examines the route designators for two

adjacent designators containing its own adapter ring number, and its colleague adapter’s ring number and

bridge number. If these combinations are detected, the frame is copied. If no such match is found, the

TMS380SRA does not enable frame coying. The TMS380SRA uses the direction bit to determine the required

8

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ꢀ ꢁꢂ ꢃꢄ ꢅꢂ ꢆꢇ

ꢂꢈ ꢉꢆꢊ ꢋꢌꢆꢈ ꢉꢀ ꢍꢎ ꢏꢐꢇꢊꢊ ꢋꢑꢋ ꢆ ꢇꢀꢈ ꢆ

ꢒ ꢒ

SPWS006 − NOVEMBER 1991

order in which the routing information should be interpreted. This allows a frame to be returned to the sender

without having to reorder the designators by changing the direction bit. If the direction bit is zero, the designators

are read from left to right; if the direction bit is one, from right to left.

The TMS380SRA does not check that the same ring number appears more than once in the routing information.

If rings 1, 2, and 3 are bridged together as a triangle, and a frame contains a sequence of designators 1, 2, 3,

1, it circulates indefinitely. Attached system software should check for this condition before forwarding the frame.

10x — Indicates that the frame is an all-routes broadcast. Every bridge forwards the frame to the next ring if

it has not already circulated on that ring or has not already traversed the maximum number of bridges permitted

by the protocol. (IBM token-ring network architecture reference limits this count to seven.) If the network is

configured so that there are several routes to the destination adapter, then as many copies are received by that

adapter as there are routes. The ring number in the final route designator of a broadcast should be the same

as the ring number of the token-ring adapter bridge that receives it for forwarding. the TMS380SRA does not

copy an all-routes broadcast frame with an incorrect final-route designator.

With broadcast frames, the value in the length field grows as the frame traverses the network. The first bridge

to forward a frame adds 4 to the value and appends its designator (ring number and bridge number) and its

colleague’s ring number to the routing-information field, leaving its colleague’s bridge number as all zeros.

Subsequent bridges forwarding the frame add 2 to the value of the length field, add their bridge number into the

all zeros bridge number part of the received final designator, and append their colleague’s designator to the

routing-information field, again leaving the colleague’s bridge number portion as all zeros.

11x — Indicates that the frame is a single-route broadcast. Only bridges that are set up to transfer single-route

broadcast frames consider the frame for forwarding. The TMS380SRA can be configured to copy single-route

broadcast frames using the SET.BRIDGE.PARMS command. Frames are copied by the TMS380SRA under the

same conditions as for all-route broadcasts. There is nothing inherent in the frame to limit its propagation to just

one route. The network manager must select which bridges forward single-route broadcast frames and inform

the bridges appropriately.

length-field requirements

The five length bits in the routing-control field indicate, in bytes, the length of the routing-information field. The

minimum value is 2, which is how all bridge-broadcast frames originate, and the maximum value supported by

the TMS380SRA is 30. All odd values, 0, 4, and values greater than 30 result in frames not being copied by the

TMS380SRA. A value of 4 is illegal since this would mean there was only one route designator present. A value

of 2 is not copied by the TMS380SRA for nonbroadcast frames.

9

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

^{POST OFFICE BOX 1443}• HOUSTON, TEXAS 77251−1443

ꢀ ꢁ ꢂꢃ ꢄꢅ ꢂꢆ ꢇ

ꢂꢈꢉ ꢆ ꢊ ꢋꢌꢆ ꢈꢉꢀ ꢍ ꢎꢏ ꢐꢇꢊ ꢊꢋ ꢑꢋ ꢆꢇꢀꢈ ꢆ

ꢒ

SPWS006 − NOVEMBER 1991

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

Supply voltage, V

(see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V

CC

Input voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V

Output voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V

Operating free-air temperature range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C

A

Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C

†

Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTE 2: Voltage values are with respect to GND.

recommended operating conditions

The TMS380SRA is designed to interface directly to the TMS380Cx6 token-ring commprocessor, Refer to the

TMS380 Second-Generation Token Ring User’s Guide (SPWS005) for details on TMS380Cx6 operation.

All inputs to the TMS380SRA have TTL compatible levels. All outputs are CMOS compatible; therefore,

like-named pins on the TMS380SRA and TMS380Cx6 should be connected together.

MIN NOM

MAX

5.5

0

UNIT

V

Supply voltage

4.5

0

5

0

CC

Supply voltage, GND (see Note 3)

V

CC

Except XMATCH and XFAIL

XMATCH and XFAIL

8

I

High-level output current

mA

OH

OL

2

Except XMATCH and XFAIL

XMATCH and XFAIL

−8

−2

70

50

20

I

Low-level output current (see Note 4)

Operating free-air temperature

mA

T

0

°C

A

MADH, MADL, MAXPH, MAXPL

XFAIL, XMATCH

C

Output load capacitance

pF

L

NOTES: 3. All GND pins should be routed to minimize inductance to system ground.

4. The algebraic convention, where the more negative (less positive) limit is designated as a minimum, is used in this data sheet for

logic voltage levels only.

electrical characteristics over recommended operating conditions (unless otherwise noted)

TEST CONDITIONS

PARAMETER

MIN

TYP

MAX

UNIT

(see Note 5)

V

High-level input voltage

V

= 5.5 V

= 4.5 V

2

V

IH

CC

Low-level input voltage, TTL-level signal

High-level output voltage, TTL-level signal

Low-level output voltage, TTL-level signal

Supply current

0.8

IL

CC

V

= MIN,

I

= MAX

3.7

V

OH

OL

CC

OL

0.5

160

15

V

CC

OL

I

V

= MAX

60

mA

pF

CC

C

Input capacitance, any input

i

Output capacitance, any output or input/output

15

pF

o

NOTE 5: For conditions shown as MIN or MAX, use the appropriate value specified under the recommended operating conditions.

10

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型号：	TMS380SRA
厂家：	TEXAS INSTRUMENTS
描述：	SOURCE-ROUTING ACCELERATOR 源路由加速器
文件：	总11页 (文件大小：165K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

TMS380SRA [TI]

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