CY74FCT399T Quadruple 2-Input Multiplexers with Storage |

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Quadruple 2-Input Multiplexers with Storage

Quadruple 2-Input Multiplexers with Storage - CY74FCT399T


The CY74FCT399T is a high-speed quad 2-input register that selects four bits of data from either of two sources (ports) under control of a common select (S) input. Selected data are transferred to a 4-bit output register synchronous with the low-to-high transition of the clock (CP) input. The 4-bit D-type output register is fully edge triggered. The data inputs (I0X, I1X) and S input must be stable only one setup time prior to, and hold time after, the low-to-high transition of CP for predictable operation. The CY74FCT399T has noninverted outputs.

This device is 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.


  • 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
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)
  • Fully Compatible With TTL Input and Output Logic Levels
  • 64-mA Output Sink Current
    32-mA Output Source Current


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Part number Order Function Technology Family VCC (Min) (V) VCC (Max) (V) Channels (#) Voltage (Nom) (V) F @ nom voltage (Max) (MHz) ICC @ nom voltage (Max) (mA) tpd @ nom Voltage (Max) (ns) Configuration Type IOL (Max) (mA) IOH (Max) (mA) Rating Operating temperature range (C) Package Group Package size: mm2:W x L (PKG) Digital input leakage (Max) (uA) ESD CDM (kV) ESD HBM (kV)
CY74FCT399T Order now Encoder     FCT     4.75     5.25     4     5     70     0.2     7     2:1     Push-pull     64     -32     Catalog     -40 to 85     SOIC | 16     16SOIC: 77 mm2: 7.5 x 10.3 (SOIC | 16)     5     0.75     2