74LVC1G123
Single retriggerable monostable multivibrator; Schmitt trigger
inputs
Rev. 4 — 27 November 2013
Product data sheet
1. General description
The 74LVC1G123 is a single retriggerable monostable multivibrator with Schmitt trigger
inputs. Output pulse width is controlled by three methods:
1. The basic pulse is programmed by selection of an external resistor (REXT) and
capacitor (CEXT).
2. Once triggered, the basic output pulse width may be extended by retriggering the
gated active LOW-going edge input (A) or the active HIGH-going edge input (B). By
repeating this process, the output pulse period (Q = HIGH) can be made as long as
desired. Alternatively an output delay can be terminated at any time by a LOW-going
edge on input CLR, which also inhibits the triggering.
3. An internal connection from CLR to the input gates makes it possible to trigger the
circuit by a HIGH-going signal at input CLR.
Inputs can be driven from either 3.3 V or 5 V devices. This feature allows the use of these
devices as translators in a mixed 3.3 V and 5 V environment. Schmitt trigger inputs,
makes the circuit highly tolerant to slower input rise and fall times.
This device is fully specified for partial power-down applications using IOFF. The IOFF
circuitry disables the output, preventing the damaging backflow current through the device
when it is powered down.
2. Features and benefits
Wide supply voltage range from 1.65 V to 5.5 V
High noise immunity
24 mA output drive (VCC = 3.0 V)
CMOS low power consumption
DC triggered from active HIGH or active LOW inputs
Retriggerable for very long pulses up to 100 % duty factor
Direct reset terminates output pulse
Schmitt trigger on all inputs
Complies with JEDEC standard:
JESD8-7 (1.65 V to 1.95 V)
JESD8-5 (2.3 V to 2.7 V)
JESD8-B/JESD36 (2.7 V to 3.6 V)
Power-on-reset on outputs
Latch-up performance exceeds 100 mA
Direct interface with TTL levels