The HEF4538BP is a dual retriggerable-resettable Monostable Multivibrator has an active low trigger/retrigger input (nA\\), an active high trigger/retrigger input (nB), an overriding active low direct reset input (nCD\\), an output (nQ) and its complement (nQ\\) and two pins (nREXT/CEXT and nCEXT, always connected to ground) for connecting the external timing components CEXT and REXT. Typical pulse width variation over the specified temperature range is ±0.2%. The multivibrator may be triggered by either the positive or the negative edges of the input pulse and will produce an accurate output pulse with a pulse width range of 10µs to infinity. The duration and accuracy of the output pulse are determined by the external timing components CEXT and REXT. The output pulse width (tW) is equal to REXT x CEXT. The linear design techniques in LOCMOS (Local Oxide CMOS) guarantee precise control of the output pulse width. A low level at nCD\ terminates the output pulse immediately.
