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USB to 3.3V TTL interface converter USB to DB9

Convert USB to 3.3-V TTL to enable easy connection of many commercial and industrial machines still using TTL as a means of communication to a laptop or PC.


8 In Stock
Same Day Shipping (before 5PM ET)
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features

  • Simply and reliably converts TTL devices to USB.
  • Perfect for field service applications.
  • USB port powered.


Many commercial and industrial machines still use the TTL interface, and to connect these deivces to modern PCs, you need a converter. The USB to 3.3-V TTL Mini Converter is small, reliable, simple, and affordable.

Just plug the converter into a computer's USB port or USB hub and install the drivers supplied on the CD-ROM. The Mini Converter appears as an additional COM port in the Windows Device Manager, so it's compatible with Windows® applications. You're ready to go—at up to 460.8 kbps!

For a USB to 5V TTL Mini Converter, see Similar Items below.
What's included:
  • USB to 3-V TTL Mini Converter
  • 3-ft. USB Cable
  • CD-ROM

  • Tech Specs

    CE Approval Yes
    Connectors Serial: DB9 Male; USB: USB Type B Female
    Data Rate Serial: Up to 460.8 kbps; USB: 12 Mbps
    Operating Temperature 32 to 158° F (0 to 70° C)
    Power From the USB port
    Size 1.3"H x 2.3"W x 0.6"D (3.2 x 5.8 x 1.6 cm)
    Weight 0.2 lb. (.1 kg) with USB cable
    What's included: - USB to 3-V TTL Mini Converter - 3-ft. USB cable - CD-ROM

    * Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.



    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $8.14

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $16.27


    Double Diamond™ Warranty (Standard)

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The USB to 3.3V TTL interface converter USB to DB9 comes with a standard 5 Year Double Diamond™ Warranty (Standard) already included.

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

    Plus, get an Extended Double Diamond Warranty.

    You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.