CD4098BE CMOS Dual Monostable Multivibrator IC

The CD4098BE dual monostable multivibrator designed specifically to ensure stable retriggerable/resettable one-shot operation for any fixed-voltage timing application. The circuit’s timing is controlled by an external resistor (RX) and an external capacitor (CX). Furthermore, the RX and CX adjustments allow for a wide variety of output pulse lengths from the Q and Q terminals. RX and CX have no effect on the time delay from trigger input to output transition (trigger propagation delay) or the time delay from set input to output transition (reset propagation delay).

Leading-edge-triggering (+TR) and trailing-edge-triggering (-TR) input provided for triggering from either edge of an input pulse. An unused +TR input tied to VSS and an unused (-TR) input tied to VDD. A RESET (on low level)  provided for immediate termination of output pulse or to prevent output pulses when power turned on. An unused RESET input  tied to VDD. However, if an entire section of the CD4098B  not used, its RESET should be tied to VSS.

MMV stands for monostable multivibrator, which is also known as a one-shot multivibrator. The duration of the pulse is governed by the R-C network, which is connected externally to the 555 timers in this pulse generator circuit IC. One state of output remains steady with such a vibrator, while the other is in a quasi-stable condition (unstable). Energy stored by an externally linked capaci­tor to a reference level for auto-triggering of output from a quasi-stable state to a stable one. As a result, the pulse width is determined by the amount of time spent in storage.

Applications: 

• Pulse delay and timing
• Pulse shaping
• Astable multivibrator