DTMF (Dual Tone Multi-Frequency) decoders are devices that receive data transmissions in amateur radio frequency bands. They constantly monitor incoming signals for valid DTMF digits. These electronic circuits decode DTMF dial tones from telephone lines into touch-tone phones via a process known as tone dialing.
The basic DTMF decoder identifies tones from a normal touch-tone phone. It then activates an LED to provide a 4-bit binary signal as an output code.
DTMF decoders are tolerant of level variations, but function optimally at a 0dB range.
What are DTMF decoders used for?
DTMF decoders increase connectivity in electronics to allow better control of applications. Home applications like alarm systems, electronic gates and garage doors, intercom systems and everyday appliances make use of DTMF functionalities.
Public switched telephone networks (PSTN) and voice response systems are other examples where DTMF application is necessary.
Types of DTMF decoders
The most common types of DTMF Decoders include 2-tone, 5-tone, multi-tone and burst-tone versions. Multi-tone decoders receive and translate multiple tones from the source, and burst-tone versions decode clashing frequencies into binary signals
Description:
Texas Instruments range of Flip-Flops and Latches from
the 74LS Family of Low Power Schottky Logic ICs. The 74LS Family use bipolar junction technology coupled with Schottky diode clamps to achieve operating speeds equal to the original 74TTL family but ...
Description:
Texas Instruments Complex Function ICs from the 74LS
Low Power Schottky Logic Family includes Binary Adders, Magnitude & Identity Comparators and 4-to-7 BCD Decoder/Drivers. The 74LS Family use bipolar junction technology coupled with Schottky diode clamps to achieve operating speeds ...
Description:
The 74HC138, 74HCT138 decodes three binary weighted address
inputs (A0, A1 and A2) to eight mutually exclusive outputs (Y0 to Y7). The device features three enable inputs (E1, E2 and E3). Every output will be HIGH unless E1 and E2 ...
Description:
The 74HC154: 74HCT154 is a 4-to-16 line decoder/demultiplexer.
It decodes four binary weighted address inputs (A0 to A3) to sixteen mutually exclusive outputs (Y0 to Y15). The device features two input enable (E0 and E1) inputs. A HIGH on either ...
