Product details

Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 6 IOH (max) (mA) -6 Input type TTL Output type CMOS Features Balanced outputs, High speed (tpd 10-50ns), Positive input clamp diode Technology family HCT Rating Catalog Operating temperature range (°C) -40 to 85
Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 6 IOH (max) (mA) -6 Input type TTL Output type CMOS Features Balanced outputs, High speed (tpd 10-50ns), Positive input clamp diode Technology family HCT Rating Catalog Operating temperature range (°C) -40 to 85
PDIP (N) 20 228.702 mm² 24.33 x 9.4
  • Operating Voltage Range of 4.5 V to 5.5 V
  • Low Power Consumption, 80-µA Max ICC
  • Typical tpd = 11 ns
  • ±6-mA Output Drive at 5 V
  • Low Input Current of 1 µA Max
  • Inputs Are TTL-Voltage Compatible
  • Lock Bus-Latch Capability
  • True Logic
  • High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads

  • Operating Voltage Range of 4.5 V to 5.5 V
  • Low Power Consumption, 80-µA Max ICC
  • Typical tpd = 11 ns
  • ±6-mA Output Drive at 5 V
  • Low Input Current of 1 µA Max
  • Inputs Are TTL-Voltage Compatible
  • Lock Bus-Latch Capability
  • True Logic
  • High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads

These octal bus transceivers are designed for asynchronous two-way communication between data buses. The control-function implementation allows for maximum flexibility in timing.

The ’HCT623 devices allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending upon the logic levels at the output-enable (OEAB and OEBA\) inputs.

The output-enable inputs disable the device so that the buses are effectively isolated. The dual-enable configuration gives the transceivers the capability to store data by simultaneously enabling OEAB and OEBA\. Each output reinforces its input in this transceiver configuration. When both OEAB and OEBA\ are enabled and all other data sources to the two sets of bus lines are in the high-impedance state, both sets of bus lines (16 total) remain at their last states. The 8-bit codes appearing on the two sets of buses are identical.

To ensure the high-impedance state during power up or power down, OEBA\ should be tied to VCC through a pullup resistor and OEAB should be tied to GND through a pulldown resistor; the minimum value of the resistor is determined by the current-sinking/current-sourcing capability of the driver.

These octal bus transceivers are designed for asynchronous two-way communication between data buses. The control-function implementation allows for maximum flexibility in timing.

The ’HCT623 devices allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending upon the logic levels at the output-enable (OEAB and OEBA\) inputs.

The output-enable inputs disable the device so that the buses are effectively isolated. The dual-enable configuration gives the transceivers the capability to store data by simultaneously enabling OEAB and OEBA\. Each output reinforces its input in this transceiver configuration. When both OEAB and OEBA\ are enabled and all other data sources to the two sets of bus lines are in the high-impedance state, both sets of bus lines (16 total) remain at their last states. The 8-bit codes appearing on the two sets of buses are identical.

To ensure the high-impedance state during power up or power down, OEBA\ should be tied to VCC through a pullup resistor and OEAB should be tied to GND through a pulldown resistor; the minimum value of the resistor is determined by the current-sinking/current-sourcing capability of the driver.

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Technical documentation

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Type Title Date
* Data sheet SN54HCT623, SN74HCT623 datasheet (Rev. C) 18 Mar 2003
Application note Implications of Slow or Floating CMOS Inputs (Rev. E) 26 Jul 2021
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
User guide LOGIC Pocket Data Book (Rev. B) 16 Jan 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004
User guide Signal Switch Data Book (Rev. A) 14 Nov 2003
Application note TI IBIS File Creation, Validation, and Distribution Processes 29 Aug 2002
Application note CMOS Power Consumption and CPD Calculation (Rev. B) 01 Jun 1997
Application note Designing With Logic (Rev. C) 01 Jun 1997
Application note SN54/74HCT CMOS Logic Family Applications and Restrictions 01 May 1996
Application note Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc 01 Apr 1996

Design & development

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Evaluation board

14-24-LOGIC-EVM — Logic product generic evaluation module for 14-pin to 24-pin D, DB, DGV, DW, DYY, NS and PW packages

The 14-24-LOGIC-EVM evaluation module (EVM) is designed to support any logic device that is in a 14-pin to 24-pin D, DW, DB, NS, PW, DYY or DGV package,

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