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ASC24T & ASC24TS: Fast Async RS232 to RS485 automatic converter







"Let me spin a very large
RS485 network for you!"

  • Fast Automatic half-duplex RS232 to RS485 2-Wire Converter

  • Data Rates up to 115.2Kbps @ 4000ft, with Auto TX Enable

  • Fast turn around to RX Mode eliminates timing problems

  • No "data collisions," and no time delays required

  • Standard and non-standard data rates OK, Automatic timing

  • Any combination of Baud Rates and ComSpec is OK

  • LED Indicators for RS485: Power(YEL), TXD(RED), RXD(GRN)

  • 22 Ohm drive protection resistors, and ESD protection

  • Wide Input Voltage Range: 8-15Vdc (Linear Regulator). 0.5W typical

  • Jumpers for Bias, Termination, Test, DTE/DCE, Speed-up

  • Operating Temperature Range: -40C to 85C (-40F to 185F)

  • Humidity Range: 10% to 90% Relative Humidity (Non-Condensing)

  • Conformal Coating Available(Call us: 513-874-4796)

General Description:

The ASC24T is a fast Asynchronous RS232 to RS485 interface converter for 2- wire, half-duplex applications, with a fast automatic TX enable circuit, that will operate at data rates up to 115.2Kbps+ @ 4000ft. The unit has jumpers for bias, termination, RS232 DTE/DCE selection, and a setting for fast responding RS485 devices. The unit has edge mounted LED indicators, a removable screw terminal connector, and with built-in ESD and over current driver protection. The ASC24T is our most popular converter for non-isolated low-cost applications.

The ASC24T is designed for office and/or light industrial applications (nonisolated), and provides superior characteristics/features normally found only on more expensive units. Can be used for point to point, or multi-drop 2-wire systems. Rev. C boards have larger LED indicators, improved timing, a "loop-back" jumper, and a temperature range of -40C to 85C (-40F to 185F).

ASC24TS is the same as the ASC24T, but has a 2-pin terminal strip for power instead of a 2.1mm center pin barrel jack.

Need something special? Please contact us. We have additional isolated and non-isolated converters, repeaters, and repeater hubs. Units are generally stock to 2-3 business days for shipment. We design and manufacturer our entire product line, and offer technical support for our units, and can offer system recommendations for your application. Please give us a call: 513-874-4796

Related Files:

pdf icon ASC24TrevB1-ds.pdf Converter Data Sheet Rev. B1
pdf icon ASC24TrevC.pdf Converter schematic/physical Rev. C
pdf icon ASC24TrevB2.pdf Converter schematic/physical Rev. B2
pdf icon ASC24TrevB1.pdf Converter schematic/physical Rev. B1
pdf icon ASC24TrevB.pdf Converter schematic/physical Rev. B
pdf icon ASC24TrevA.pdf Converter schematic/physical Rev. A
pdf icon ASC24TSrevB.pdf Converter schematic/physical Rev. B
pdf icon ASC24TSrevA.pdf Converter schematic/physical Rev. A


RS232: 3-wire interface to RJ11/12 Connector (TX, RX, Common)
RS485: Removable screw terminal (TX/RX+, TX/RX-, Common)
Power: 2-pin terminal strip
LEDs Power(YEL), TX-RS485(RED), and RX-RS485(GRN)
Bias: 620 Ohm pull-up and pull-down (jumper selectable)
Termination:  120 Ohm (jumper selectable)
Special: Jumper selection for fast responding RS485 devices
Protection:  Up to 400W typical per SN75LBC184P specification


Distance: RS485 up to 4000 ft. (1250 meters)
Operation: 2-wire half-duplex RS485 Data
Format: Asynchronous data with any combination of bits, parity, stop
Speed: Up to 115.2Kbps (slew limited driver)
Temperature:  0-65C (32-150F) ambient
Humidity: 10-90% non-condensing
Voltage: 8-12VDC
Power:  Under 1/2 Watt(typical) + external load
Size: 2.50" X 2.00" X 0.9" (PC Board), with connectors: 2.50" X 2.25"
Mounting:  4-Holes at 2.00" X 1.50" (built-in standoffs for #6 hardware)


ASC24T: $45.00 ea. (Circuit board only)
Enclosure: $8.00 ea. (Small)
Cable: $7.50 ea. (RS232, 7 ft., Specify DB9F-7 or DB25F-7) 
Supply: $8.50 ea. (12VDC @ 200/300 mA wall power supply)
*ASC24T with all options (DB9F cable/Enclosure/PS): ASC24T-B9FSPS @ $70.00 ea. (Qty. 1-9)

Need a different configuration or more information? Give Ron a Call at 513-874-4796 or 513-638-0228(Cell)


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