The ’HC4538 and ’HCT4538 are dual retriggerable/resettable monostable precision multivibrators for fixed voltage timing applications. An external resistor (R_X) and an external capacitor (C_X) control the timing and the accuracy for the circuit. Adjustment of R_X and C_X provides a wide range of output pulse widths from the Q and Q\ terminals. The propagation delay from trigger input-to-output transition and the propagation delay from reset input-to-output transition are independent of R_X and C_X.

Leading-edge triggering (A) and trailing edge triggering (B)\ inputs are provided for triggering from either edge of the input pulse. An unused "A" input should be tied to GND and an unused B\ should be tied to V_CC. On power up the IC is reset. Unused resets and sections must be terminated. In normal operation the circuit retriggers on the application of each new trigger pulse. To operate in the non-triggerable mode Q\ is connected to B\ when leading edge triggering (A) is used or Q is connected to A when trailing edge triggering (B)\ is used. The period (. C_MIN is 0pF.

• Retriggerable/Resettable Capability
• Trigger and Reset Propagation Delays Independent of RX, CX
• Triggering from the Leading or Trailing Edge
• Q and Q\ Buffered Outputs Available
• Separate Resets
• Wide Range of Output Pulse Widths
• Schmitt Trigger Input on A and B\ Inputs
• Retrigger Time is Independent of CX
• Fanout (Over Temperature Range)
  • Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads
  • Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
• Wide Operating Temperature Range . . . –55°C to 125°C
• Balanced Propagation Delay and Transition Times
• Significant Power Reduction Compared to LSTTL Logic ICs
• HC Types
  • 2V to 6V Operation
  • High Noise Immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5V
• HCT Types
  • 4.5V to 5.5V Operation
  • Direct LSTTL Input Logic Compatibility, VIL = 0.8V (Max), VIH = 2V (Min)
  • CMOS Input Compatibility, Il 1μA at VOL, VOH

• Number of channels (#)
• 2
• Supply voltage (Min) (V)
• 4.5
• Supply voltage (Max) (V)
• 5.5
• Technology Family
• HCT
• Input type
• TTL-Compatible CMOS
• Output type
• Push-Pull
• ICC (uA)
• 80
• IOL (Max) (mA)
• 4
• IOH (Max) (mA)
• -4
• Features
• Balanced outputs, High speed (tpd 10-50ns), Positive input clamp diode, Retriggerable

CD74HCT4538的完整型号有：CD74HCT4538E、CD74HCT4538M、CD74HCT4538M96、CD74HCT4538MT，以下是这些产品的关键参数及官网采购报价：

CD74HCT4538E，工作温度：-55 to 125，封装：PDIP (N)-16，包装数量MPQ：25个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：NIPDAU，TI官网CD74HCT4538E的批量USD价格：.234（1000+）

CD74HCT4538M，工作温度：-55 to 125，封装：SOIC (D)-16，包装数量MPQ：40个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网CD74HCT4538M的批量USD价格：.406（1000+）

CD74HCT4538M96，工作温度：-55 to 125，封装：SOIC (D)-16，包装数量MPQ：2500个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网CD74HCT4538M96的批量USD价格：.206（1000+）

CD74HCT4538MT，工作温度：-55 to 125，封装：SOIC (D)-16，包装数量MPQ：250个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网CD74HCT4538MT的批量USD价格：.406（1000+）

14-24-LOGIC-EVM — 支持 14 到 24 引脚 PW、DB、D、DW、NS、DYY 和 DGV 封装的通用逻辑 EVM

该 EVM 设计用于支持采用 14 至 24 引脚 D、DW、DB、NS、PW、DYY 或 DGV 封装的任何逻辑器件。