CD74AC257

Features:

• CD74AC257, CD74ACT257 . . . . . Non-Inverting Outputs
• CD74ACT258 . . . . . . . . . . . . . . . . . . . Inverting Outputs
• Buffered Inputs
• Typical Propagation Delay
  - 4.4ns at V_CC = 5V, T_A = 25, C_L = 50pF
• Exceeds 2kV ESD Protection MIL-STD-883, Method 3015
• SCR-Latchup-Resistant CMOS Process and Circuit Design
• Speed of Bipolar FAST™/AS/S with Significantly Reduced Power Consumption
• Balanced Propagation Delays
• AC Types Feature 1.5V to 5.5V Operation and Balanced Noise Immunity at 30% of the Supply
• ±24mA Output Drive Current
  - Fanout to 15 FAST™ ICs
  Drives 50W Transmission Lines


Pinout




Specifications

DC Supply Voltage, V_CC . . . . . . . . . . . . . . . . . . . . . . .  . -0.5V to 6V
DC Input Diode Current, I_IK
For V_I < -0.5V or V_I > V_CC + 0.5V . . . . . . . . . . . . . . .  . . . . .±20mA
DC Output Diode Current, I_OK
For V_O < -0.5V or V_O > V_CC + 0.5V . . . . . . . . . . . . . . . . . .. .±50mA
DC Output Source or Sink Current per Output Pin, I_O
For V_O > -0.5V or V_O < V_CC + 0.5V . . . . . . . . . . . . . . . .  .  . .±50mA
DC V_CC or Ground Current, I_CC or I_GND (Note 3) . . . . . .  . .±100mA 


Description

The CD74AC257, CD74ACT257 and CD74ACT258 are quad 2-input multiplexers with three-state outputs that utilize the Harris Advanced CMOS Logic technology. Each of these devices selects four bits of data from two sources under the control of a common Select input (S). The CD74AC257 Output Enable (OE) is active LOW. When OE is HIGH, all of the outputs (Y or Y) are in the high-impedance state regardless of all other
input conditions.

Moving data from two groups of registers to four common output buses is a common use of the CD74AC257, CD74ACT257 and CD74ACT258. The state of the Select input determines the particular register from which the data comes. The CD74AC257, CD74ACT257 and CD74ACT258 can also be used as function generators.