iButton® Specialist and Manufacturer of Dallas Keys



Can you advise what’s meant by a GENERIC iButton®?

Scenario: Purchasing have asked me (as the responsible Engineer) to approve its use. The device in question has a “TM” pre-fix in front of the 1990A and another has no prefix in front of the 1990A. I’m suspicious and looking for clarification.


Authentic iButton® have a Registered Symbol, a Registered Protocol called 1-Wire® and a Prefix “DS” in front of the device type EG DS1990A-F5.

The terminology GENERIC is completely out of context when referencing iButton®. It's either an Authentic iButton® designed and Registered by Dallas Semiconductor or an attempt to copy and imply the right to do so.                                                            

If the part is marketed or sold as an iButton® without these Registration Symbols, it’s being sold illegally and is Counterfeit. There are a number of prominent Suppliers marketing their wares as iButton® and misleading their Customers and the Market.

    Equally and if not more important, Counterfeit iButtons® are compromising the Security of the system they were intended to protect. At Design inception iButton® would have been chosen for 2 important reasons which Counterfeit parts fail to provide-

    • Authentic iButton’s have a guaranteed Unique 16 Digit ID which is achieved by digital engraving on the Silicon at the point of manufacture making it almost impossible to copy. There is scrutiny at the manufacturing point to ensure each device conforms to a controlled Data Base.
    • Counterfeit parts can have their ID’s easily copied and put into other parts breaking the security integrity intended.

    It’s important in the context of considering to use a Counterfeit part, iButton® is NOT a typical Semiconductor. Typically, if the part number is the same across several manufacturers, it would imply an identical Electrical Specification and each would work in the application.

    Whilst (naturally) the Electrical Specification of an iButton® is important, it also has one addition important parameter being the “UNIQUE ID”. This point it typically misunderstood when looking at an alternative. The Unique ID coupled with the difficulty of it being copied is the prime Intellectual Property of iButton® and the reason for selection as a technology in Money transaction and Security sensitive applications such as EPOS Terminals and Cash Transportation.

    In short you have the right to be suspicious and concerned as Counterfeit iButton®'s do not afford the same level of Security as intended when Authentic iButton® was chosen at system point of design. Copied iButton® potentially allow Hackers access to Back Office Bank Records and Client Credit Card details.



    Why is there an availability issue with iButton?


    iButton® is of the Semiconductor Silicon family generically known as “Micro Chip’s”. You will be aware (and I’m sure have already been impacted) of Chip shortages impacting Car Manufacturing and many other end equipment’s using Electronic Component.

    The problem-

    • There is an increasing tendency for application to move to DIGITAL solutions EG Electronics in Cars etc
    • Manufacturing down turn and lack of Investment in new Silicon Factories caused by the impact of Covid and 1 year Lockdown resulting in Factory closures
    • Reduced confidence in investing in new Plant which typically cost 100+ Billion Dollar and take 1+ year to complete
    • The result of a instantaneous need for switch on following Lockdown after 1 year+ closure and lack of investment caught the market short.
    • Prior to Lockdown many Silicon Chip companies moved their manufacturing to third party vendors and were/are one step removed for having control of their own destiny.

    The above has resulted in severe shortage of Silicon manufacturing and every Silicon Vendor found themselves having the need to increase lead times from weeks to in some cases years.

    Maxim has typically gone from what was a 8 week lead time to (say) an average of 53 weeks which is unprecedented but not limited only to them.

    • As an example the most popular part (by quantity) is the DS1990 and the manufacturing lead time is 50 weeks. A more complex part (having additional memory) DS1973 is presently on a 120 week lead time
    • iButton® is made up from a low power CMOS Technology which is relatively specialised and as a consequence of using a third party their options are limited.

    It’s our opinion the Silicon Manufacturing constraints driving lead times are with us for the next 2 years.

    It’s important to realise, whilst, there is a close link to Manufacturing lead time and actual Availability, companies like ourselves are likely to have stock but still faced with a challenge as it’s impossible to satisfy every Customers need.

    At IMAC Electronics, the process of Customer Service and how we support the market, is based on Customer Allocation. As a rule of thumb if you are a historic and loyal Customer it’s likely your need will be supported. If you are a new Customer with no track record, then it’s unlikely, whilst faced with the current shortage. Keeping control in any business is paramount warranting some tough decisions.

    The only way to keep control of Customer Service, in a shortage environment, is to operate an Allocation System being the fairest and most tangible way. Many of our Customers have not been impacted by the Market shortage as we have a history made up over several years and organise our Customer Service accordingly.



      Why has the price of iButton® increased in recent months?


      The main reason is Silicon Manufacturing shortages. Maxim use a Third Party diffusion Company and find themselves having to bid in the open Market for capacity against many of their competitors.

      As a consequence Maxim are not offering supportive nor (as) flexible pricing as they can sell everything they can secure several times over. There has also been an increasing tendency to change their price list over time and to increase pricing on Customer backlog with limited notice.

      The other big factor in recent months is the Dollar/Pound Currency Rate of Exchange. Maxim’s manufacturing Cost and selling Currency to the UK is in Dollar. The Dollar/Pound Exchange Rate has gone (in September) as low as 1.09 forcing a Pound increaseof some 20+%.

      Challenging times and whilst we have limited influence, on buy price from Maxim, we will react to the Dollar/Pound Rate of Exchange
      as it varies.