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RFIDAK
Factory-direct manufacturer

iButton, DS1990 & Touch Memory keys — straight from the factory

We manufacture DS1990A / DS1990R / TM1990A keys, RW1990 rewritable blanks, readers, probes and accessories — fully compatible with Dallas / Maxim, at factory-direct pricing with full OEM/ODM support.

  • 100% read-tested before packing
  • Custom ROM ranges & laser marking
  • Shipping to 40+ countries
TM1990A colour keys and a DS1990A-compatible steel iButton
5,000,000 pcsMonthly capacity
100 pcsMOQ
2010Making TM keys since
40+Countries served
RFIDAK

Why source from us

01

Factory-direct pricing

No middlemen. Our prices sit well below original-brand cost, and volume tiers start at low MOQ.

02

Own silicon, deep OEM

Our DS1990A-compatible chip is designed in-house — beyond drop-in interchangeability, we can customise the family code (01h → any value) and the CRC rule for closed systems.

03

Ready stock, short lead times

Popular SKUs ship from stock; OEM runs are scheduled in days, not months.

04

Full OEM / ODM

Custom ROM coding, colours, casing, laser marking and your logo — plus private-label packaging.

1-Wire®

How Touch Memory identification works

Three facts explain why this 1990s technology still guards millions of doors: a globally unique ROM, a one-wire read, and a can built like a tool.

64 bit8488Family codeUnique serial numberCRC01 · 00 00 15 8D 42 7A · 6C
64-bit ROM: 8-bit family code + 48-bit serial + 8-bit CRC

A 64-bit identity, burned at the factory

Every key carries an 8-bit family code, a 48-bit unique serial and an 8-bit CRC, lasered into ROM at production. 2⁴⁸ combinations mean no two keys collide — and the CRC lets any reader verify the number it just read.

A can built like a tool, not a card

The stainless MicroCan survives a 1.5 m drop to concrete, 500 g shock and one million touch cycles per the iButton standard — which is why field failures are lost keys, not dead ones.

01158D427AID OKDATAGND
One data line + ground: the reader powers the key and reads its ROM in under 5 ms

One touch, one wire, under 5 ms

The 1-Wire® bus carries power and data on a single line at 16.3 kbit/s. The key needs no battery — it is parasite-powered by the reader — so there is nothing to charge, drain or jam.

Mechanical and protocol figures per the Analog Devices (Dallas/Maxim) iButton standards and DS1990A datasheet.

Production & quality control

From wafer to sealed carton

Contact keys are a volume business, so the things that actually determine whether a shipment is good happen on the assembly floor — not in a brochure.

  1. 01
    Incoming IC batch test
  2. 02
    ROM & CRC verification
  3. 03
    Press-fit & laser marking
  4. 04
    100% function read test
  5. 05
    High-temp & seal sampling
  6. 06
    ESD packing & docs
5 M+ / moMonthly output
100%100% of units, not sampled
< 0.1%Defect rate
About →
Built for buyers who resell
350 M+

iButton devices shipped worldwide since the technology launched — per Analog Devices, which acquired original maker Maxim Integrated in 2021 and keeps the line in production.

Distributors, key-cutting chains, telematics vendors and system integrators buy consumables monthly. Everything below exists to make the second order easier than the first.

ISO 9001CERoHSREACH
Shipping to 40+ countries

Technical guide

Reference material on Touch Memory and 1-Wire identification — compatibility, family codes, common questions and how to source these parts properly. Written by people who make them.

All technical articles →

DS1990A vs TM1990A vs RW1990: what is the difference?

A plain comparison of the read-only DS1990A, its TM1990A equivalent, the rewritable RW1990 blank and the universal Cyfral/Metakom blanks — what each one is for, whether it can be copied, and which readers accept it.

iButton / 1-Wire family code reference table

The first two hex digits of a 1-Wire ROM identify the device type. This reference table maps the common family codes to their iButton and 1-Wire part numbers, so you can identify any key from its printed ID.

Touch Memory & iButton FAQ

Straight answers to the questions buyers and installers actually ask about iButton, DS1990A, TM keys, rewritable blanks, readers, compatibility, lifetime and ordering.

How to wire a Touch Memory reader (TM+, TM−, LED)

The four wires on a TM reader, what each one does, why the LED circuit is independent of the key circuit, and the mistakes that cause a reader to “not work” when it is actually wired backwards.

1-Wire protocol timing: reset, presence, read and write slots

The actual timing numbers behind a 1-Wire key transaction — reset and presence pulse windows, write-1 and write-0 slots, the read sampling window, plus ROM command codes and electrical limits. Measured values from our PR1990 key IC datasheet.

OEM & ODM options: colours, laser marking, ROM ranges, packaging

Exactly what can be customised on a Touch Memory key and what each option costs you in MOQ and lead time — housing colours, your logo, reserved ID ranges, fob assembly and retail packaging.

Request a quote

Tell us the models and quantities you need. We normally reply within one working day with pricing and samples.

Request a quote