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Quadruple 2-Input Multiplexers With Storage


Package | PIN: N | 16
Temp: C (0 to 70)
Carrier: Partial Tube
Qty Price
1-9 $2.27
10-24 $2.03
25-99 $1.89
100-249 $1.65
250-499 $1.52
500-749 $1.27
750-999 $1.05
1000+ $0.96


  • Single-Rail Outputs on 'LS399
  • Selects One of Two 4-Bit Data Sources and Stores Data Synchronously with System Clock
  • Applications:
    • Dual Source for Operands and Constants in Arithmetic Processor; Can Release Processor Register Files for Acquiring New Data
    • Implement Separate Registers Capable of Parallel Exchange of Contents Yet Retain External Load Capability
    • Universal Type Register for Implementing Various Shift Patterns: Even Has Compound Left-Right Capabilities


Texas Instruments  SN74LS399N

This monolithic quadruple two-input multiplexer with storage provides essentially the equivalent functional capabilities of two separate MSI functions (SN54LS157/SN74LS157 and SN54LS175/SN74LS175) in a single 16-pin package.

When the word-select input is low, word 1 (A1, B1, C1, D1) is applied to the flip-flops. A high input to word select will cause the selection of word 2 (A2, B2, C2, D2). The selected word is clocked to the output terminals on the positive-going edge of the clock pulse.

Typical power dissipation is 37 milliwatts. The SN54LS399 is characterized for operation over the full military range of -55°C to 125°C. The SN74LS399 is characterized for operation from 0°C to 70°C.