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Async RS232 to 5V TTL interface converter DB9 to DB9

Convert USB to 5-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.


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

*Required field

Product Features

  • Simply and reliably converts 5-V TTL devices to USB.
  • USB port powered.
  • Perfect for field service applications.


The RS-232 to TTL Converter enables you to control TTL devices. The converter is fast, too—it supports serial data rates of up to 115 kbps!

Just plug it in and you're ready to go. This tiny converter takes almost no space at all, and you can use it with virtually any micro controller or programmable logic controller that supports TTL.

It also converts two channels (TX and RX) in each direction from RS-232 to TTL.

Tech Specs

CE Approval Yes
Connectors RS-232: (1) DB9 F; TTL: (1) DB9 M
Power From the RS-232 interface
RoHS Yes
Size 2.2"H x 2.2"W x 0.6"D (5.6 x 5.6 x 1.5 cm)

* 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: $7.30

Extended 3 Year Warranty Available

Protect your purchase with an additional 3 Year Double Diamond™ warranty!
Cost: $14.59


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 Async RS232 to 5V TTL interface converter DB9 to DB9 comes with a standard 1 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.