RS485 is too expansive: any replacement?

Hi,

 I'm called to design a multi drop network where the nodes communicate
using 2 wires.
 The distance from 2 nodes is maximum 20 meters. The wires will run
along the mains (220 V).

 I requested a quotation for the following part:

                     MAX3483ECSA (3 Volt, ESD protetected,
transceiver)

 and they told me that 4000 parts cost 1.90 Euros each... amazing!

 Are there any cheaper pin-to-pin part replacement?

 Does, using CAN transceivers instead of RS485 ones, make any sense?

thanks for any help,
 Enrico

zigbee@libero.it wrote:
> Hi,
> 
>  I'm called to design a multi drop network where the nodes communicate
> using 2 wires.
>  The distance from 2 nodes is maximum 20 meters. The wires will run
> along the mains (220 V).
> 
>  I requested a quotation for the following part:
> 
>                      MAX3483ECSA (3 Volt, ESD protetected,
> transceiver)
> 
>  and they told me that 4000 parts cost 1.90 Euros each... amazing!
> 
>  Are there any cheaper pin-to-pin part replacement?
> 
>  Does, using CAN transceivers instead of RS485 ones, make any sense?

Yes, if you do not need >> 1Mbd.
The Atmel ATA6660 lists just under US 65c/2K
Specs +/- 10V CMR, and +/-40V protection, and 8KV ESD

The TJA1050 is a similar price, but lower ESD spec

-jg

On Fri, 06 Jul 2007 00:19:52 -0700, the renowned zigbee@libero.it
wrote:

>Hi,
>
> I'm called to design a multi drop network where the nodes communicate
>using 2 wires.
> The distance from 2 nodes is maximum 20 meters. The wires will run
>along the mains (220 V).
>
> I requested a quotation for the following part:
>
>                     MAX3483ECSA (3 Volt, ESD protetected,
>transceiver)
>
> and they told me that 4000 parts cost 1.90 Euros each... amazing!
>
> Are there any cheaper pin-to-pin part replacement?
>
> Does, using CAN transceivers instead of RS485 ones, make any sense?
>
>thanks for any help,
> Enrico

The 75176 is about 1/10 of that price, but 5V only. 


Best regards, 
Spehro Pefhany
-- 
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

In comp.arch.embedded,
zigbee@libero.it <zigbee@libero.it> wrote:
> Hi,
>
>  I'm called to design a multi drop network where the nodes communicate
> using 2 wires.
>  The distance from 2 nodes is maximum 20 meters. The wires will run
> along the mains (220 V).

Distance between 2 nodes <= 20 meters, but what is the maximum
total length of the bus? Bitrate?

>  I requested a quotation for the following part:
>
>                      MAX3483ECSA (3 Volt, ESD protetected,
> transceiver)
>
>  and they told me that 4000 parts cost 1.90 Euros each... amazing!
>
>  Are there any cheaper pin-to-pin part replacement?

Have a look at Sipex. Replace MAX with SP, works with al lot of
maxim parts and Sipex is usually cheaper.

The cheapest is probably the standard 75176, but that's 5V and no
extended ESD protection...

>  Does, using CAN transceivers instead of RS485 ones, make any sense?

Well it can work I suppose, but will they be any cheaper? You will
ofcourse want the automotive, 3V, ESD, etc. version.

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

Un bel giorno zigbee@libero.it digit�:

>  I requested a quotation for the following part:
> 
>                      MAX3483ECSA (3 Volt, ESD protetected,
> transceiver)
> 
>  and they told me that 4000 parts cost 1.90 Euros each... amazing!

The same part costs 1.67 euros for 1000 pcs on Digikey.

>  Are there any cheaper pin-to-pin part replacement?

SN65HVD12D (1.66 euros for 5k units on Digikey) looks pin-to-pin
compatible. Plus, it's not Maxim.

>  Does, using CAN transceivers instead of RS485 ones, make any sense?

Not really, if you need a pin-to-pin compatible with MAX3483.

-- 
emboliaschizoide.splinder.com