Product details

Supply voltage (min) (V) 4.75 Supply voltage (max) (V) 5.25 Number of channels 8 IOL (max) (mA) 64 IOH (max) (mA) -32 Input type TTL Output type TTL Features Partial power down (Ioff), Very high speed (tpd 5-10ns) Technology family FCT Rating Catalog Operating temperature range (°C) -40 to 85
Supply voltage (min) (V) 4.75 Supply voltage (max) (V) 5.25 Number of channels 8 IOL (max) (mA) 64 IOH (max) (mA) -32 Input type TTL Output type TTL Features Partial power down (Ioff), Very high speed (tpd 5-10ns) Technology family FCT Rating Catalog Operating temperature range (°C) -40 to 85
SOIC (DW) 24 159.65 mm² 15.5 x 10.3 SSOP (DBQ) 24 51.9 mm² 8.65 x 6
  • Function, Pinout, and Drive Compatible With FCT and F Logic
  • Reduced VOH (Typically = 3.3 V) Versions of Equivalent FCT Functions
  • Edge-Rate Control Circuitry for Significantly Improved Noise Characteristics
  • Ioff Supports Partial-Power-Down Mode Operation
  • Matched Rise and Fall Times
  • Fully Compatible With TTL Input and Output Logic Levels
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)
  • Independent Register for A and B Buses
  • CY54FCT646T
    • 48-mA Output Sink Current
    • 12-mA Output Source Current
  • CY74FCT646T
    • 64-mA Output Sink Current
    • 32-mA Output Source Current
  • 3-State Outputs

  • Function, Pinout, and Drive Compatible With FCT and F Logic
  • Reduced VOH (Typically = 3.3 V) Versions of Equivalent FCT Functions
  • Edge-Rate Control Circuitry for Significantly Improved Noise Characteristics
  • Ioff Supports Partial-Power-Down Mode Operation
  • Matched Rise and Fall Times
  • Fully Compatible With TTL Input and Output Logic Levels
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)
  • Independent Register for A and B Buses
  • CY54FCT646T
    • 48-mA Output Sink Current
    • 12-mA Output Source Current
  • CY74FCT646T
    • 64-mA Output Sink Current
    • 32-mA Output Source Current
  • 3-State Outputs

The \x92FCT646T devices consist of a bus transceiver circuit with 3-state, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked into the registers as the appropriate clock pin goes to a high logic level. Output-enable (G\) and direction (DIR) inputs control the transceiver function. In the transceiver mode,data present at the high-impedance port can be stored in either the A or B register, or in both. Select controls (SAB, SBA) can multiplex stored and real-time (transparent mode) data. DIR determines which bus receives data when G\ is low. In the isolation mode (G\ is high), A data can be stored in the B register and/or B data can be stored in the A register.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.

The \x92FCT646T devices consist of a bus transceiver circuit with 3-state, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked into the registers as the appropriate clock pin goes to a high logic level. Output-enable (G\) and direction (DIR) inputs control the transceiver function. In the transceiver mode,data present at the high-impedance port can be stored in either the A or B register, or in both. Select controls (SAB, SBA) can multiplex stored and real-time (transparent mode) data. DIR determines which bus receives data when G\ is low. In the isolation mode (G\ is high), A data can be stored in the B register and/or B data can be stored in the A register.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.

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Technical documentation

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Type Title Date
* Data sheet 8-Bit Registered Transceivers With 3-State Outputs datasheet (Rev. A) 01 Oct 2001
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
Application note Selecting the Right Level Translation Solution (Rev. A) 22 Jun 2004
User guide CYFCT Parameter Measurement Information 02 Apr 2001
Selection guide Advanced Bus Interface Logic Selection Guide 09 Jan 2001

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,

User guide: PDF | HTML
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SOIC (DW) 24 View options
SSOP (DBQ) 24 View options

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