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???
09/12/11 13:30
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#183719 - Alas, "weak output drive" and no input hysterese
Responding to: ???'s previous message
"The NTB0104 is a 4-bit, dual supply translating transceiver with auto direction sensing, that enables bidirectional voltage level translation."

The auto direction sensing part sounds interesting. If all I needed was just level shifting, then 74HCT can manage quite well, but these chips might be able to solve the data direction problem while still taking care of power dissipation for inadvertently loaded outputs, and the required noise immunity of a transceiver.

But there seems to be two issues.

1) There is no mention of any hysterese on inputs.

2) I'm not sure if they are strong enough for driving ribbon-cable signals.

"In a static state, the output drivers of the NTB0104 can maintain a defined
output level, but the output architecture is designed to be weak, so that
they can be overdriven by an external driver when data on the bus starts
flowing in the opposite direction."

So I see lots of potential for them - the price is nice too - but probably only for on-board level conversion.

From the datasheets it's a bit hard to figure out their actual drive capabilities, so I should probably get some samples to play around with, even if I do not think they are usable for this specific project.

List of 40 messages in thread
TopicAuthorDate
Bit-configurable transceiver chips            01/01/70 00:00      
   Suggesting....again...            01/01/70 00:00      
      Alas 5V needed and ribbon cables are a bit "rough"            01/01/70 00:00      
   Another Suggestion....            01/01/70 00:00      
   level translator            01/01/70 00:00      
      Alas, "weak output drive" and no input hysterese            01/01/70 00:00      
      TI sn74gtl2010            01/01/70 00:00      
         or NXP GTL2010,GTL2000            01/01/70 00:00      
            looks promising            01/01/70 00:00      
            NXP GTL20xx -> NVT20xx            01/01/70 00:00      
         Need to read more to understand them            01/01/70 00:00      
            looks like the cat's miauw            01/01/70 00:00      
   NXP has ....            01/01/70 00:00      
      I2C or SPI just can't get even close to the huge bandwidth            01/01/70 00:00      
         nope, no I²C clocks            01/01/70 00:00      
            extender, not expander            01/01/70 00:00      
   I have been wondering this myself            01/01/70 00:00      
      Supported capacitance seems to be the snag            01/01/70 00:00      
   Differential SPI            01/01/70 00:00      
      Serial -> buffers on adapter boards is a potential solution            01/01/70 00:00      
   Have you considered programmable logic?            01/01/70 00:00      
      I had suggested this as well            01/01/70 00:00      
         Yes ... I remember that ...            01/01/70 00:00      
            Long life            01/01/70 00:00      
               They seem to live a long time ...            01/01/70 00:00      
                  Adapters            01/01/70 00:00      
                     These aren't necessarily so "huge"            01/01/70 00:00      
                        Not huge in size            01/01/70 00:00      
                           Some of them can handle that.            01/01/70 00:00      
                              Yes and no            01/01/70 00:00      
                                 There are ways ...            01/01/70 00:00      
                                    Body diodes            01/01/70 00:00      
                                       serial termination ...            01/01/70 00:00      
                                          Yes, current- and bandwidth-limiting components used            01/01/70 00:00      
                                             you youing whippersnappers, pay attention            01/01/70 00:00      
            pedantry, again            01/01/70 00:00      
               What would YOU suggest?            01/01/70 00:00      
   Here's a thought ...            01/01/70 00:00      
      Probably            01/01/70 00:00      
         I'd sugest you consider older CPLD's            01/01/70 00:00      

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