Loading ...
Sorry, an error occurred while loading the content.
 

Re: [Electronics_101] Optoisolator for TTL level 115,200 baud serial data

Expand Messages
  • kabowers336
    ... The SI87xx series of drop-in replacements looks interesting too. I looked at the article and it appears the SI8421 is treated just like a gate; no pullups.
    Message 1 of 8 , Sep 4, 2013
      On Tue, 3 Sep 2013 23:29:11 -0400, you wrote:

      >> From: Howard Hansen
      >>
      >> Another possibility is a a SI8421. See:
      >> <http://www.silabs.com/Support%20Documents/TechnicalDocs/si8410.pdf>
      >> It is not an optical isolator. But the SI8421 is a digital isolator and is
      >rated at 150
      >> megabits per second.
      >>
      >> The author of an article in the September 2013 issue of Circuit Cellar
      >uses the
      >> SI8421 to interface an ATMEGA328P with a Raspberry Pi at
      >> 115,200 bps. No design information in the article. He just provides a
      >summary
      >> of why he used a SI8421. The name of the article is Raspberry PI I/O
      >Board.
      >>
      >> The other Howard
      >
      >I just skimmed the datasheet and it looks like just what I need, Thanks much
      >...
      >
      >I wasn't able to see the article because I haven't subscribed to Circuit
      >Cellar for many years (can't keep up with everything as it is!) ... but
      >maybe I should reconsider ....
      >
      >Thanks again.

      >Cheers,
      >
      >Chuck Hackett
      >
      The SI87xx series of drop-in replacements looks interesting too.

      I looked at the article and it appears the SI8421 is treated just like a
      gate; no pullups. It does appear the parts really want the 0.1uF
      bypass caps on both Vcc supplies.

      Circuit Cellar was bought out by Elektor some time ago. They
      started a new format with the September issue.

      I was a charter Circuit Cellar subscriber (1988) and have a major
      pile of the magazines. Switched to electronic only last year.
      The electronic version works well.

      Keith Bowers WB4LSJ- Thomasville, NC
    • Howard Hansen
      ... Why do you say the SI87xx series look interesting. They would not be suitable for chuck s application. They are not a dual channel device. They only
      Message 2 of 8 , Sep 4, 2013
        On 9/4/2013 8:02 AM, kabowers@... wrote:
         

        On Tue, 3 Sep 2013 23:29:11 -0400, you wrote:

        >> From: Howard Hansen
        >>
        >> Another possibility is a a SI8421. See:
        >> <http://www.silabs.com/Support%20Documents/TechnicalDocs/si8410.pdf>
        >> It is not an optical isolator. But the SI8421 is a digital isolator and is
        >rated at 150
        >> megabits per second.
        >>
        >> The author of an article in the September 2013 issue of Circuit Cellar
        >uses the
        >> SI8421 to interface an ATMEGA328P with a Raspberry Pi at
        >> 115,200 bps. No design information in the article. He just provides a
        >summary
        >> of why he used a SI8421. The name of the article is Raspberry PI I/O
        >Board.
        >>
        >> The other Howard
        >
        >I just skimmed the datasheet and it looks like just what I need, Thanks much
        >...
        >
        >I wasn't able to see the article because I haven't subscribed to Circuit
        >Cellar for many years (can't keep up with everything as it is!) ... but
        >maybe I should reconsider ....
        >
        >Thanks again.

        >Cheers,
        >
        >Chuck Hackett
        >
        The SI87xx series of drop-in replacements looks interesting too.


        Why do you say the SI87xx series look interesting.   They would not be suitable for chuck's application.  They are not a dual channel device.  They only have one channel.  However, they could be useful when you need isolation for signals greater than 5 volts.

        The other Howard



        I looked at the article and it appears the SI8421 is treated just like a
        gate; no pullups. It does appear the parts really want the 0.1uF
        bypass caps on both Vcc supplies.

        Circuit Cellar was bought out by Elektor some time ago. They
        started a new format with the September issue.

        I was a charter Circuit Cellar subscriber (1988) and have a major
        pile of the magazines. Switched to electronic only last year.
        The electronic version works well.

        Keith Bowers WB4LSJ- Thomasville, NC

        __

      • kabowers336
        ... His original post stated that a single was acceptable. Keith Bowers WB4LSJ- Thomasville, NC
        Message 3 of 8 , Sep 4, 2013
          On Wed, 04 Sep 2013 18:30:22 -0500, you wrote:

          >On 9/4/2013 8:02 AM, kabowers@... wrote:
          >>
          >> On Tue, 3 Sep 2013 23:29:11 -0400, you wrote:
          >>
          >> >> From: Howard Hansen
          >> >>
          >> >> Another possibility is a a SI8421. See:
          >> >> <http://www.silabs.com/Support%20Documents/TechnicalDocs/si8410.pdf>
          >> >> It is not an optical isolator. But the SI8421 is a digital isolator
          >> and is
          >> >rated at 150
          >> >> megabits per second.
          >> >>
          >> >> The author of an article in the September 2013 issue of Circuit Cellar
          >> >uses the
          >> >> SI8421 to interface an ATMEGA328P with a Raspberry Pi at
          >> >> 115,200 bps. No design information in the article. He just provides a
          >> >summary
          >> >> of why he used a SI8421. The name of the article is Raspberry PI I/O
          >> >Board.
          >> >>
          >> >> The other Howard
          >> >
          >> >I just skimmed the datasheet and it looks like just what I need,
          >> Thanks much
          >> >...
          >> >
          >> >I wasn't able to see the article because I haven't subscribed to Circuit
          >> >Cellar for many years (can't keep up with everything as it is!) ... but
          >> >maybe I should reconsider ....
          >> >
          >> >Thanks again.
          >> >
          >> >Cheers,
          >> >
          >> >Chuck Hackett
          >> >
          >> The SI87xx series of drop-in replacements looks interesting too.
          >>
          >
          >Why do you say the SI87xx series look interesting. They would not be
          >suitable for chuck's application. They are not a dual channel device.
          >They only have one channel. However, they could be useful when you need
          >isolation for signals greater than 5 volts.
          >
          >The other Howard
          >
          >
          >>
          >> I looked at the article and it appears the SI8421 is treated just like a
          >> gate; no pullups. It does appear the parts really want the 0.1uF
          >> bypass caps on both Vcc supplies.
          >>
          >> Circuit Cellar was bought out by Elektor some time ago. They
          >> started a new format with the September issue.
          >>
          >> I was a charter Circuit Cellar subscriber (1988) and have a major
          >> pile of the magazines. Switched to electronic only last year.
          >> The electronic version works well.
          >>
          >> Keith Bowers WB4LSJ- Thomasville, NC
          >>
          >> _
          His original post stated that a single was acceptable.
          Keith Bowers WB4LSJ- Thomasville, NC
        Your message has been successfully submitted and would be delivered to recipients shortly.