SMSC TMC2005-JT User Manual

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TMC2005-JT

ARCNET 5 Port HUB Controller

FEATURES

ARCNET HUB Circuit for ARCNET Protocol (Data Rate From 156.25Kbps to 10Mbps)

Able to Connect Various Transceivers Directly

Device Includes TX/RX Timing Circuit for 5 Port Hub and Direction Control Circuit, Jitter Correct Circuit and Noise Cancel Circuit

Easy to Design 8 or 12 Port Hub

Can Connect with HYC9088 in Normal Mode

Can Connect with RS485 Transceiver, HYC5000/4000/2000, Opt Module and TTL Interface in Backplane Mode

Supports both Normal and Backplane Mode at the Same Time for Media Conversion

+ 5V Single Power

GENERAL DESCRIPTION

When configuring a network, the maximum number of nodes and the maximum cable length are limited by the electric capacity of the transceiver. In this case, the network is expanded by an equipment called a “HUB” or “repeater”. It maybe necessary to have a converter between coax, T/P and the fiber cable. It is easy to design a HUB or a repeater because the TMC2005 has various features for expanding such network.

It can connect with HYC9088, RS485 transceiver, HYC5000/4000/2000 and TTL interface for optical module. It can connect with three different transceivers at the same time and convert the media of each. (The data rate cannot be converted. It is necessary to operate all nodes in the same network at the same data rate). The Hubs can be expanded by connecting two or more TMC2005 chips. By setting one of 5 ports to open-drain output, the Hub can be expanded to either 12 or 16 ports.

ORDERING INFORMATION

Order Number(s):

TMC2005-JT for 64 pin, TQFP Lead-Free RoHS Compliant Package

SMSC TMC2005-JT

Revision 1.1 (07-24-07)

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

80 ARKAY DRIVE, HAUPPAUGE, NY 11788 (631) 435-6000, FAX (631) 273-3123

Copyright © 2007 SMSC or its subsidiaries. All rights reserved.

Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications. Consequently, complete information sufficient for construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders.

SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT; TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Revision 1.1 (07-24-07)

Page 2

SMSC TMC2005-JT

DATASHEET

 

ARCNET 5 Port HUB Controller

 

Datasheet

TABLE OF CONTENTS

 

FEATURES..................................................................................................................................................................

1

GENERAL DESCRIPTION.......................................................................................................................................

1

PIN CONFIGURATION ............................................................................................................................................

4

BLOCK DIAGRAM....................................................................................................................................................

4

BLOCK DIAGRAM....................................................................................................................................................

5

DESCRIPTION OF PIN FUNCTIONS ....................................................................................................................

5

DESCRIPTION OF PIN FUNCTIONS ....................................................................................................................

6

TX/RX INTERFACE....................................................................................................................................................

7

OPERATING MODE SETUP ..........................................................................................................................................

8

PLL ...........................................................................................................................................................................

8

OTHER SIGNALS ........................................................................................................................................................

9

OPERATIONAL DESCRIPTION...........................................................................................................................

10

DIRECTION DETERMINATION ...................................................................................................................................

10

DIRECTION RELEASE ...............................................................................................................................................

10

JITTER FILTER..........................................................................................................................................................

10

OPTION FEATURE FOR JITTER FILTERING.................................................................................................................

11

OPTION FEATURE FOR NOISE CUT MODE .................................................................................................................

11

APPLICATION NOTES ........................................................................................................................................

12

PORT GROUP...........................................................................................................................................................

20

VARIOUS SETUP.......................................................................................................................................................

20

EXAMPLE FOR OPERATION MODE SETUP TO EACH PORT........................................................................................

20

NOTE FOR UNUSED PORT .........................................................................................................................................

20

EXAMPLE FOR POWER-ON RESET CIRCUIT ..............................................................................................................

20

CONNECTING THE TMC2005 WITH INTERNAL PLL...................................................................................

21

METHOD TO CONNECT A CRYSTAL CLOCK.............................................................................................................

22

NPLLTST PIN..........................................................................................................................................................

22

CASCADING CONNECTION ................................................................................................................................

23

RING NETWORK WITH THE TMC2005.....................................................................................................................

26

MAXIMUM GUARANTEED RATINGS*............................................................................................................

27

STANDARD OPERATING CONDITION ............................................................................................................

27

DC CHARACTERISTIC - INPUT PIN ..................................................................................................................

27

DC CHARACTERISTIC - OUTPUT PIN ..............................................................................................................

28

AC CHARACTERISTIC - CLOCK AND RESET...................................................................................................

28

AC CHARACTERISTIC – RX WAVEFORMS AND TX WAVEFORMS ........................................................................

29

TMC2005-JT 64 PIN TQFP PACKAGE OUTLINE.............................................................................................

31

SMSC TMC2005-JT

Page 3

Revision 1.1 (07-24-07)

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

PIN CONFIGURATION

 

MB

RXINB1 LB TXENB0 SB RXINB0 VSS8 NC VDD6 TXENA1 MA RXINA1 LA TXENA0

SA RXINA0

 

 

64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49

 

TXENB1

1

 

48

VSS7

HM

2

 

47

nPULSE1

SE

3

 

46

nPULSE2

NC

4

 

45

nP1BAK

LE

5

 

44

VDD5

EXTRX

6

 

43

nCKOEN

ME

7

TMC2005-JT

42

nRST

EXTTX

9

40

nBJA

VSS1

8

 

41

VSS6

VDD1

10

 

39

nBJB

CKO

11

 

38

nBJE

VSS2

12

 

37

nMBA

CKM2

13

 

36

nMBB

CKM1

14

 

35

nMBE

CKM0

15

 

34

nEXTOD

NC

16

 

33

NC

 

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

 

 

RXFLT

nPLLTST VDD2 XTLI XTLO VSS4 NC VDD4 VDD3 AVDD R0 LP AGS AVSS VSS3 VSS5

 

Revision 1.1 (07-24-07)

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SMSC TMC2005-JT

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

BLOCK DIAGRAM

 

 

 

nBJB nMBE

nMBA

MB

 

LB

 

 

SE SB SA

 

nBJE

nBJA nMBB

ME

MA

LE

LA

nEXTOD

RXINA0

NOT

 

 

 

 

 

OR

 

 

NOT

TXENA0

RXINA1

 

 

 

 

 

 

 

Circuit

 

 

 

 

 

Circuit

 

 

Circuit

TXENA1

RXINB0

NOT

 

 

 

 

 

OR

 

 

NOT

TXENB0

RXINB1

 

 

 

 

 

 

 

Circuit

 

Direction Control

 

Circuit

 

 

Circuit

TXENB1

 

 

 

 

 

 

 

 

 

Circuit

 

 

 

 

 

 

 

EXTRX

NOT

 

 

 

 

 

OR

 

 

NOT

 

 

 

 

 

 

 

 

 

 

 

Circuit

 

 

 

 

 

Circuit

 

 

Circuit

 

HM

 

 

 

 

 

 

 

 

 

 

 

RXFLT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output

 

 

 

 

 

 

 

 

 

 

 

Control

EXTTX

 

 

 

 

 

 

 

 

 

 

Circuit

 

 

 

 

 

 

 

 

Rx

 

Tx

nP1BAK

 

 

 

 

 

 

 

 

 

Pulse

nPULSE1

 

 

 

 

 

 

 

 

Buffer

 

 

 

 

 

 

 

 

 

 

Gen.

nPULSE2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DPLL

 

 

 

VSS1-8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VDD1-6

Clock Multiplier

 

 

 

 

 

 

 

 

 

 

XTLO

PLL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AND

 

 

 

 

 

 

XTLI

 

 

 

 

 

 

 

 

 

CKO

AVDD

 

 

 

 

Circuit

 

 

 

 

 

AVSS

 

 

 

 

 

 

 

 

 

 

 

nRST

 

 

 

 

 

 

 

 

 

 

 

CKM0

CKM2

AVSS

 

RO

nCKOEN

 

 

 

 

 

CKM1 nPLLTST

LP

 

 

 

 

 

 

 

 

SMSC TMC2005-JT

 

 

 

 

Page 5

 

 

 

Revision 1.1 (07-24-07)

 

 

 

 

DATASHEET

 

 

 

 

ARCNET 5 Port HUB Controller

Datasheet

DESCRIPTION OF PIN FUNCTIONS

PIN NO.

NAME

INPUT/OUTPUT

DESCRIPTION

NOTE

1

TXENB1

OUTPUT

Port B-1 Tx output to media transceiver

 

 

 

 

Setting for traffic release time (It should

 

2

HM

INPUT

be open for normal operation.)

Pull-up

 

 

 

Port EXT. Polar assignment for EXTRX

 

3

SE

INPUT

input (0:active Hi, 1:active Low)

Pull-up

4

NC

 

Reserved. It should be open.

 

 

 

 

Port EXT. Polar assignment of EXTTX

 

5

LE

INPUT

output (0:active Low, 1:active Hi)

Pull-up

 

 

 

Port EXT. RX-Data input from media

 

6

EXTRX

INPUT

transceiver.

Pull-up

 

 

 

Port EXT. Output mode assignment of

 

 

 

 

EXTTX (0:pulse output, 1:Tx control

 

7

ME

INPUT

output)

Pull-up

8

VSS1

 

Ground

 

9

EXTTX

OUTPUT

Port EXT. Output to media transceiver.

 

10

VDD1

 

Power Supply

 

11

CKO

OUTPUT

Clock Output

 

12

VSS2

 

Ground

 

13

CKM2

INPUT

Network speed (data rate) setting.

Pull-up

14

CKM1

INPUT

 

Pull-up

15

CKM0

INPUT

 

Pull-up

16

NC

 

Reserved. It should be open.

 

17

RXFLT

INPUT

Test Pin. It should be open.

Pull-up

 

 

 

Test Pin for PLL.. It should connected to

 

18

nPLLTST

INPUT

VDD (Set to high)

 

19

VDD2

 

Power Supply

 

20

XTLI

INPUT

X'tal input/External clock input.

 

21

XTLO

OUTPUT

X'tal output

 

22

VSS4

 

Ground

 

23

NC

 

Reserved. It should be open.

 

24

VDD4

 

Power Supply

 

25

VDD3

 

Power Supply

 

26

AVDD

 

Analog Power Supply

 

27

RO

OUTPUT

VCO output for internal PLL.

 

 

 

 

Connection pin to loop filter for internal

 

28

LP

OUTPUT

PLL.

 

29

AGS

INPUT

Analog sense pin for internal PLL.

 

30

AVSS

 

Analog Ground

 

31

VSS3

 

Ground

 

32

VSS5

 

Ground

 

33

NC

 

Reserved. It should be open.

 

 

 

 

Port EXT. Open-drain mode (0:open-

 

34

nEXTOD

INPUT

drain output, 1:normal output)

Pull-up

35

nMBE

INPUT

Port EXT. Noise cut (0:on, 1:off)

Pull-up

36

nMBB

INPUT

Port A0/A1 Noise cut (0:on, 1:off)

Pull-up

37

nMBA

INPUT

Port B0/B1 Noise cut (0:on, 1:off)

Pull-up

 

 

 

Port EXT. Jitters correct mode (0:big

 

38

nBJE

INPUT

jitters mode, 1:normal mode)

Pull-up

 

 

 

Port A0/A1 Jitters correct mode (0:big

 

39

nBJB

INPUT

jitter mode, 1:normal mode)

Pull-up

 

 

 

Port B0/B1 Jitter correct mode (0:big

 

40

nBJA

INPUT

jitter mode, 1:normal mode)

Pull-up

41

VSS6

 

Ground

 

42

nRST

INPUT

Internal reset signal (active Low)

Pull-up

43

nCKOEN

INPUT

Enable of CKO output.

Pull-up

Revision 1.1 (07-24-07)

 

Page 6

SMSC TMC2005-JT

DATASHEET

 

 

 

 

 

 

 

 

 

 

 

ARCNET 5 Port HUB Controller

 

 

 

 

 

 

 

 

 

 

 

 

Datasheet

 

 

 

 

 

 

 

 

 

 

 

 

 

PIN NO.

 

NAME

 

INPUT/OUTPUT

DESCRIPTION

NOTE

44

 

 

VDD5

 

 

 

 

 

Power Supply.

 

 

 

45

 

 

nP1BAK

 

 

 

OUTPUT

nPULSE1 output (for backplane mode).

 

 

46

 

 

nPULSE2

 

 

OUTPUT

nPULSE2 output (for normal mode).

 

 

47

 

 

nPULSE1

 

 

OUTPUT

nPULSE1 output (for normal mode)

 

 

48

 

 

VSS7

 

 

 

 

 

Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

Port A-0 Rx-data input from media

 

 

49

 

 

RXINA0

 

 

 

INPUT

transceiver.

 

Pull-up

 

 

 

 

 

 

 

 

 

 

Port A. Polar assignment for RXINA0/A1

 

 

50

 

 

SA

 

 

 

INPUT

output (0:active Hi, 1:active Low)

Pull-up

51

 

 

TXENA0

 

 

 

OUTPUT

Port A-0 Tx output to media transceiver.

 

 

 

 

 

 

 

 

 

 

 

 

Port A. Polar assignment for TXENA0/A1

 

 

52

 

 

LA

 

 

 

INPUT

output (0:active Low, 1:active Hi)

Pull-up

 

 

 

 

 

 

 

 

 

 

Port A-1 Rx-data input from media

 

 

53

 

 

RXINA1

 

 

 

INPUT

transceiver.

 

Pull-up

 

 

 

 

 

 

 

 

 

 

Port A. Mode assignment for

 

 

 

 

 

 

 

 

 

 

 

 

TXENA0/A1 (0:pulse output, 1:Tx control

 

 

54

 

 

MA

 

 

 

INPUT

output)

 

Pull-up

55

 

 

TXENA1

 

 

 

OUTPUT

Port A-1 Tx output to media transceiver.

 

 

56

 

 

VDD6

 

 

 

 

 

Power Supply

 

 

 

57

 

 

NC

 

 

 

 

 

Reserved. It should be open.

 

 

58

 

 

VSS8

 

 

 

 

 

Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

Port B-0 Rx-data input from media

 

 

59

 

 

RXINB0

 

 

 

INPUT

transceiver.

 

Pull-up

 

 

 

 

 

 

 

 

 

 

Port B. Polar assignment for RXINA0/A1

 

 

60

 

 

SB

 

 

 

INPUT

input (0:active Hi, 1:Active Low)

Pull-up

61

 

 

TXENB0

 

 

 

OUTPUT

Port B-0 Tx output to media transceiver.

 

 

 

 

 

 

 

 

 

 

 

 

Port B. Polar assignment for TXENA0/A1

 

 

62

 

 

LB

 

 

 

INPUT

output (0:active Low, 1:active Hi)

Pull-up

 

 

 

 

 

 

 

 

 

 

Port B-1 Rx-data input from media

 

 

63

 

 

RXINB1

 

 

 

INPUT

transceiver.

 

Pull-up

 

 

 

 

 

 

 

 

 

 

Port B. Mode assignment for

 

 

 

 

 

 

 

 

 

 

 

 

TXENA0/A1 (0:pulse output, 1:TX control

 

 

64

 

 

MB

 

 

 

INPUT

output)

 

Pull-up

Note: Pull-up: Input with a pull-up resistor 70KΩ ± 30%

 

 

 

TX/RX Interface

 

 

 

 

 

 

 

 

 

 

 

 

 

 

FEATURE

 

NAME

 

INPUT/OUTPUT

DESCRIPTION

 

 

 

RX Port

 

 

 

 

RXINA [0:1]

 

INPUT

Setup the polarity by SA, SB, SE.

 

 

 

 

 

 

 

 

 

RXINB [0:1]

 

 

 

 

 

 

 

 

 

 

 

 

 

EXTRX

 

 

 

 

 

 

 

RX Port

 

Polar

 

SA, SB, SE

 

INPUT

Setup the polarity of RXINA [0:1],

 

 

 

 

 

Assignment

 

 

 

 

RXINB [0:1], EXTTX.

 

 

 

 

 

 

 

 

 

 

 

 

 

0 : active H

 

 

 

 

 

 

 

 

 

 

 

 

 

1: active L

 

 

 

 

TX Port

 

TX Control

 

TXENA [0:1]

 

OUTPUT

TX data pulse (Mx=0) or TX

 

 

 

 

 

 

 

 

 

TXENB [0:1]

 

 

enable signal (Mx=1).

 

 

 

 

 

 

 

 

 

 

EXTTX

 

 

Setup TX mode by MA, MB, ME.

 

 

 

 

 

 

 

 

 

 

 

 

Setup the polarity by LA, LB, LE

 

 

 

TX Port

 

TX Data

 

nPULSE [1:2]

 

OUTPUT

TX pulse data into HYC9068S-

 

 

 

 

 

 

Output

 

 

 

 

SK/9088S-SK when ARCNET

 

 

 

 

 

 

 

 

 

 

 

 

chip is at normal mode.

 

 

 

 

 

 

 

 

 

 

 

 

 

The pulse is always active Low.

 

 

 

TX Port

 

 

 

 

nP1BAK

 

OUTPUT

TX pulse data into RS485 driver

 

 

 

 

 

 

 

 

 

 

 

 

or HYC2485S/2488S when

 

 

 

 

 

 

 

 

 

 

 

 

ARCNET chip is at backplane

 

SMSC TMC2005-JT

 

 

 

 

 

Page 7

 

Revision 1.1 (07-24-07)

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

 

 

 

 

FEATURE

NAME

 

 

 

INPUT/OUTPUT

 

DESCRIPTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

mode.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The pulse is always active Low.

 

 

TX Port

 

 

Polarity

LA, LB, LE

 

 

 

 

INPUT

 

Setup the polarity of TXENA

 

 

 

 

 

Setup

 

 

 

 

 

 

 

 

[0:1], TXENB [0:1], EXTTX.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0 : active L

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1: active H

 

 

 

 

TX Port

 

Mode Setup

MA, MB, ME

 

 

 

 

INPUT

 

Setup the mode of TXENA [0:1],

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TXENB [0:1], EXTTX.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0: Output TX pulse. (It is

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

equivalent to nTXEN “OR”

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

nP1BAK)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1: Output TX enable

 

Operating Mode Setup

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

INPUT/

 

 

 

 

 

 

 

 

 

 

 

 

 

FEATURE

 

NAME

OUTPUT

 

 

 

 

 

 

DESCRIPTION

 

 

 

 

Data rate

 

CKM [0:2]

INPUT

 

Terminal to setup the data rate of TMC2005.

 

 

 

setup

 

 

 

 

 

CKM2 CKM1 CKM0 DIVISOR MULTIPLIER

SPEED

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

0

0

16

 

x1

156.25 Kbps

 

 

 

 

 

 

 

 

 

0

0

1

8

 

x1

312.5 Kbps

 

 

 

 

 

 

 

 

 

0

1

0

4

 

x1

625 Kbps

 

 

 

 

 

 

 

 

 

0

1

1

2

 

x1

1.25 Mbps

 

 

 

 

 

 

 

 

 

1

0

0

1

 

x1

2.5 Mbps

 

 

 

 

 

 

 

 

 

1

0

1

1

 

x2

5 Mbps

 

 

 

 

 

 

 

 

 

1

1

0

Reserved

Reserved

Reserved

 

 

 

 

 

 

 

 

 

1

1

1

1

 

x4

10 Mbps

 

 

 

 

 

 

 

 

 

 

External clock is 20MHz.

 

 

 

 

 

 

 

 

 

 

 

 

 

Refer to “VARIOUS SETUP”

 

 

 

 

 

Noise cut

 

nMBA

INPUT

 

0: Cut off noise from received data

 

 

 

 

mode

 

nMBB

 

 

1: Don’t cut off noise

 

 

 

 

 

 

 

 

nMBE

 

 

Setup “0” normally.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Big jitter

 

nBJA

INPUT

 

Setup a jitter filter feature.

 

 

 

 

 

mode

 

nBJB

 

 

Select a pulse as reference phase used by DPLL.

 

 

 

 

 

nBJE

 

 

0: 2nd pulse (big jitter mode)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1: 1st pulse (normal mode)

 

 

 

 

 

Open drain

 

nEXTOD

INPUT

 

Setup a the use of EXTTX port.

 

 

 

 

mode

 

 

 

 

 

0: Set EXTTX as open drain output and use as Ext.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1: Set EXTTX as normal output and use as 5th port.

 

PLL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

INPUT/

 

 

 

 

 

 

 

 

 

 

 

 

FEATURE

 

NAME

 

OUTPUT

 

 

 

 

 

DESCRIPTION

 

 

 

 

 

 

LP

 

OUTPUT

 

 

Using PLL: Connect to an external condenser

 

 

 

 

 

 

 

 

 

 

 

“C1” for loop filter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Using no PLL: must be open.

 

 

 

 

 

 

 

RO

 

OUTPUT

 

 

VCO output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Using PLL: Connect to an external resistor “R0” for

 

 

 

 

 

 

 

 

 

 

 

loop filter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Using no PLL: must be open.

 

 

 

 

 

 

 

AGS

 

INPUT

 

 

Analog sense input.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Using PLL: Connect to loop filter.

 

 

 

 

 

 

 

 

 

 

 

 

 

Using no PLL: Connect to ground.

 

 

 

Revision 1.1 (07-24-07)

 

 

 

 

 

 

 

 

Page 8

 

 

 

 

SMSC TMC2005-JT

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

 

 

 

INPUT/

 

 

 

 

FEATURE

NAME

OUTPUT

 

 

DESCRIPTION

 

 

nPLLTST

INPUT

Test pin for PLL.

 

 

 

 

 

Must always connect to VDD.

 

 

AVDD

 

 

Analog power supply

 

 

 

 

 

Using PLL: Analog power supply. There are some

 

 

 

 

 

limits on PCB pattern.

 

 

 

 

 

Using no PLL: Power supply (+5V) same as VDD1~6.

 

 

AVSS

 

 

Analog ground

 

 

 

 

 

 

Using PLL: Analog ground. There are some limits on

 

 

 

 

 

PCB pattern.

 

 

 

 

 

 

Using no PLL: Use a ground same as VSS1~8.

Other Signals

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

INPUT/

 

 

 

FEATURES

NAME

 

OUTPUT

 

DESCRIPTION

 

CRYSTAL

XTLI

 

INPUT

 

Connect a 20MHz crystal.

 

INTERFACE

 

 

 

 

When supplying an external clock,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

input the clock to this pin.

 

CRYSTAL

XTLO

 

OUTPUT

 

Connect a 20MHz crystal.

 

INTERFACE

 

 

 

 

When supplying an external clock, it

 

 

 

 

 

 

 

must be open.

 

SYSTEM RESET

nRST

 

INPUT

 

Reset for initializing TMC2005. (active

 

INTERFACE

 

 

 

 

Low)

 

TEST PIN

CKO

 

OUTPUT

 

Output internal clock of TMC2005.

 

TEST PIN

nCKOEN

 

INPUT

 

Output control of CKO.

 

 

 

 

 

 

 

0: Output internal clock on CKO.

 

 

 

 

 

 

 

1: Always output Low level on CKO.

 

 

 

 

 

 

 

Set “1” Normally.

 

TEST PIN

RXFLT

 

INPUT

 

It must be open

 

TEST PIN

NC [1:2]

 

 

 

It must be open

 

POWER SUPPLY

VDD [1:6]

 

 

 

Power supply (+5V)

 

GROUND

VSS [1:8]

 

 

 

Ground

SMSC TMC2005-JT

Page 9

Revision 1.1 (07-24-07)

DATASHEET

ARCNET 5 Port HUB Controller

Datasheet

OPERATIONAL DESCRIPTION

Direction Determination

All TX ports are set to disable mode in the initial state. When a signal is received from any RX ports, the circuit holds the port on receiving mode (disable TX) and changes the other ports to sending mode (disable RX). One port stays in RX and the rest change into TX after all. The circuit initializes the internal DPLL on the timing of received RX pulse, and the RX buffer circuit stores the RX data and filters its jitter. TX controlling circuit regenerates the stored RX pulse on nPULSE1, nPULSE2 and nP1BAK. The nPULSE1 and nPULSE2 are pulse output pins for transceivers (HYC9088A) of ARCNET normal mode. The nP1BAK is a pulse output pin for transceiver (HYC5000/4000/2000 and RS485 driver) of ARCNET back plane mode. When using optical transceiver, instead of these signals, TXENA [0:1], TXENB [0:1], EXTTX (MA, MB, ME = 0) must be used as TX data inputs of the optical transceiver.

Direction Release

On ARCNET protocol, each TX message starts with 6-bits of “1” ALERT and each data byte is lead by three bits (1, 1, 0) preamble. To control the HUBs direction, the circuit monitors this bit pattern and holds the state. If the end of the bit pattern comes, all TX ports return receiving mode (disable TX) again. The interval timer detects the end of the bit pattern. During data is on line, silent period is less than 4 uS* because at least one bit “1” among 10-bits is received while receiving the data. The minimum silent interval from the end of received data to the alert of the next data (the minimum time of changing the direction) is the chip turn around time (12.6 uS*) of ARCNET controller. The interval timer to detect the data end is set to 5.6uS by adding some margin to the above interval for neglecting the reflection on a cable.

[Note] Numbers marked * are at 2.5Mbps operation.

Jitter Filter

To build a network with transceivers that introduce big jitter like ones for optical fiber, the old HUB that has direction control only may cause a transmission error because jitters on each HUB are added when several HUBs were connected in serial. The TMC2005 fixes that problem with jitter filtering and wave shaping through the following three steps.

1)Input Sampling

The TMC2005 samples a data on a network by eight times clock of the network data.

2)Jitter Filtering (DPLL)

The TMC2005 filters the jitter (± 100nS at 2.5Mbps) of network data sampled by 8X clock through the internal digital PLL and stores the data into the buffer.

3)Wave Shaping Output

The TMC2005 re-synchronizes and regenerates the network data at the same clock as the data rate.

The capability of the jitter filtering is shown below.

DATA RATE

CAPABILITY OF JITTER FILTERING

10Mbps

± 25nS

5Mbps

± 50nS

2.5Mbps

± 100nS

1.25Mbps

± 200nS

625Kbps

± 400nS

312.5Kbps

± 800nS

156.25Kbps

± 1.6uS

Revision 1.1 (07-24-07)

Page 10

SMSC TMC2005-JT

DATASHEET

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