The application of PEB2254 and PEB22554

[Serg_SV]

peb22554

Hi,
I have used Peb22554 with transformer T1144 and PEB2254 with transformer РЕ-68786. My schematic I done in accordance with your application, but I don't know How can I calculate length trace line taking into account parameter's cable? I usually use twin-axial cable 75 Om or twisted-pair cable 120 Om. Have you any application for decide my problem?
For example, I have used twisted-pair cable with diameter lead of a cable 0.4 mm, lead of a cable has electric resistance 139 Om and mutual capacitance 50nF on 1 kilomete length, attenuation constant 1.54dB on 1 kilomete length. What max length of cable I can to use for Peb22554 and PEB2254?

 

[papyaki]

Re: user's PEB2254, PEB22554

Hi,

Never seen cable with attenuation of 1.54db per kilometer. Should be 1.54 db per 100 meters or 15.4db per kilometer.

PEB2254 is designed for short haul applications. Input sensitivity is arround -16db of g703 nominal level at 2.37V for 75ohms lines. So with a cable with an attenuation of 15.4db per kilometer, you can use a 1 kilometer line.

PEB22554 is designed for long haul and short haul applications. Long haul sensitivity is arround -43db. of g703 nominal level at 2.37V. So with a cable with an attenuation of 15.4db per kilometer, you can use an over 2.5 kilometer line.

Be carefull of the best sensitivity given in de datasheets. In practice, due to your design (connectors, PCB trace etc.), real short haul sensitivity will be arround -12db and long haul sensitivity arround -36db/-38db of nominal level.

 

[Serg_SV]

Re: user's PEB2254, PEB22554

Hi,

Never seen cable with attenuation of 1.54db per kilometer. Should be 1.54 db per 100 meters or 15.4db per kilometer.

PEB2254 is designed for short haul applications. Input sensitivity is arround -16db of g703 nominal level at 2.37V for 75ohms lines. So with a cable with an attenuation of 15.4db per kilometer, you can use a 1 kilometer line.

PEB22554 is designed for long haul and short haul applications. Long haul sensitivity is arround -43db. of g703 nominal level at 2.37V. So with a cable with an attenuation of 15.4db per kilometer, you can use an over 2.5 kilometer line.



Be carefull of the best sensitivity given in de datasheets. In practice, due to your design (connectors, PCB trace etc.), real short haul sensitivity will be arround -12db and long haul sensitivity arround -36db/-38db of nominal level.

Thank you for you answer.
For example twisted-pair cable UTP2-24R5

 

[papyaki]

Re: user's PEB2254, PEB22554

Hi,

Can you upload (or given a link to) the english datasheet of this cable ?

 

[Serg_SV]

Re: user's PEB2254, PEB22554

Hi,

Can you upload (or given a link to) the english datasheet of this cable ?

I be mistaken, you right.
I am going to use 600S series 22AWG
**broken link removed**

Only I don't understand, 1.5dB/100m for signal E1, it for one lead of a cable or two leads of a cable?

 

[papyaki]

Re: user's PEB2254, PEB22554

Hi,

I think you mean 600C 22AWG. This is a 100 ohms T1/DSX1. This reference do not provide shielding between pairs. It can introduce some crosstalk between pairs, so I think it is to be used only in short haul applications with low attenuations. Be careful if you want to use it on E1 networks, which have a 120 ohms impedance, not 100 ohms.

1.5db/100m is for one pair (2 leads). This attenuation is given for a frequency, generaly 772kHz for T1 transmission or 1024kHz for E1 transmissions.

 

[Serg_SV]

user's PEB2254, PEB22554

Hi,
it's cable 22 AWG advise to use Infineon for PEB22554. In data sheet PEB22554 Version 1.3 from July 2000 they wrote in section 4.1.3 "Receive Equalization Network (E1)": The QuadFALC™ automatically recovers the signals received on pins RL1/2 in a range of up to -43 dB. The maximum reachable length with a 22 AWG twisted pair cable is 1500m. (look page 59).
Therefore, if do calculation on condition that 1.5db/100m is for one pair (2 leads) and maximum line attenuation up to -43 dB at 1024 kHz (E1), I get length twisted pair cable is 2750m and line attenuation -41.25dB. Not coincide with data sheet.

If suppose, that 1.5db/100m is for one lead from pair, that length with a 22 AWG twisted pair cable is 1500m has max line attenuation -45dB.
Where does misprint? What are you think about that?

 

[papyaki]

Re: user's PEB2254, PEB22554

Hi,

The cable you want to use is one of the best with an attenuation of 1.5db per 100m. In E1 network, you can find shielded twisted pair cables with attenuation of 2.5db per 100m or more, due to the shield. Generaly, in E1 networks, we use shielded cables, not unshielded as you want to use.

Infineon is probabely refering such shielded cable in their datasheet.