SN74LS122DR

Overview

The SN74LS122DR is a retriggerable monostable multivibrator manufactured by Texas Instruments, belonging to the SN74LS logic series. It features a single element in a 14-SOIC surface-mount package. The device operates within a supply voltage range of 4.75 V to 5.25 V and supports a maximum power current of 6 mA. Key electrical parameters include a propagation delay of 56 ns, a low-level output current of 8 mA, and a high-level output current of -400 uA. It functions across an operating temperature range from 0°C to +70°C.

Feature Summary

• Retriggerable monostable operation allows pulse width extension upon receiving subsequent trigger signals during the timing interval.
• Integrated internal discharge transistor facilitates external RC timing circuit connections for precise pulse duration control.
• Schmitt-trigger inputs provide noise immunity and clean signal transitions for reliable triggering.

Applications

• Pulse generation and timing circuits
• Debouncing mechanical switches
• Frequency division

Procurement Notes

Verify the component authenticity against official Texas Instruments documentation. Confirm the specific ordering suffix matches the required package and tape-and-reel specifications. Ensure compatibility with standard SOIC-14 footprint designs. Check RoHS compliance status if environmental regulations apply to the final assembly.

Selection Notes

Select this component when a retriggerable monostable function is required within the LS logic family constraints. Compare propagation delay and output drive capabilities against system requirements. Consider the 14-SOIC package dimensions for PCB layout optimization. Evaluate thermal performance within the specified commercial temperature range.

Part Context

This part belongs to the SN74LS122 family of monostable multivibrators. It shares functional similarities with other LS-series timers but offers specific retriggering capabilities. The DR suffix indicates a tape-and-reel packaging format suitable for automated surface-mount assembly processes.

Replacement Considerations

SN74LS122DRE4 is listed as a manufacturer-recommended alternative, though it may be discontinued in some channels. Verify pinout and electrical characteristics before substitution.