All You Wanted to Know About DB9 Connectors

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All You Wanted to Know About DB9 Connectors
If you deal in cable and connectors, you
must have come across the term DB9 Connector.
This connector is named like that because of its
trapezoidal shape that looks like letter "D". It
has been designed in such a way that it can work
with EIA/TIA 232 serial interface standard
and used for Serial Asynchronous Data
Transmission. You will find DB9 Connectors
used with computer, audio/video, and data
applications. DB9 ports were quite popular during
the initial years but with the
introduction of usb, firewire etc its
popularity declined.
The RS 232 is the recommended standard for
enabling serial data transfer between DCE (Data
Circuit-terminating Equipment) and DTE (Data
Terminal Equipment). When you buy these
connectors, you can recognize them by the
letters A to E that denote the shell size and
also by the number of pins. M or F indicates
whether it is a male or a female connector.
Let us know more about these connectors,
their types, electrical specifications and
applications
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DB9 Connector Sizes and Types DB stands for D
sub or D subminiature. However, its real
name is DE-9. There are times when DE-9 D-sub
9-pin connector is wrongly referred to as "DB-9
connector". Here, "E" refers to the shell size.
Every shell size of DB9 connector corresponds
to a particular number of sockets or
pins. For example, A with 15, B with 25, E with
9 and so on DB9 indicates 9 position shell and 9
indicates contact terminals. They were used a lot
in PC. Db-xx on the other hand is used for all
types of serial connectors.

• Electrical specifications of DB9 Connectors
• Rating 3 Amps max
• Contact resistance 20 mOhms max
• Operation voltage 250VAC max
• Insulation resistance 3000 MOhms min at 1000 VDC
  between
• Dielectric withstanding voltage 1000 VAC min rms
  (sea level)

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Application of DB9 connectors DB9 connectors are
used for the following purposes

• To connect peripheral devices in the outdated pcs
• With keyboard, mouse and joysticks
• ?

• In microprocessors evaluation programming
• Stepper and servo motor interface
• Modem and network

board, circuit boards etc while
There are several firms through which you
can buy DB9 serial cables and connectors
online including SF Cable. You can get in touch
with their experts and seek their advice before
deciding on the type of cable you want. Once you
get insights about the kind of cable you need,
you can order it online. Make sure you are clear
with the specifications and usage before you
order for these cables and connectors.
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