74HCT221D,118

74HCT221 Dual non-retriggerable monostable multivibrator with reset Rev. 3 26 October 2016 Product data sheet 1. General description The 74HCT221 is a dual non-retriggerable monostable multivibrator. Each multivibrator features edge-triggered inputs (nA and nB), either of which can be used as an enable input. Pulse triggering occurs at a particular voltage level and is not directly related to the transition time of the input pulse. Schmitt-trigger input circuitry for the nB inputs allow jitter-free triggering from inputs with slow transition rates, providing the circuit with excellent noise immunity. Once triggered, the outputs (nQ, nQ) are independent of further transitions of nA and nB inputs. The output pulse width is defined by the following relationship: t = 0.7 C R The output pulses can be terminated by the active W EXT EXT LOW reset inputs (nRD). Pulse width stability is achieved through internal compensation and is virtually independent of V and temperature. In most applications pulse stability CC will only be limited by the accuracy of the external timing components. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of V . CC 2. Features and benefits Input levels: For 74HCT221: TTL level Pulse width variance is typically less than 5% Direct reset terminates output pulse Schmitt-trigger action on nB inputs ESD protection: HBM JESD22-A114F exceeds 2000 V MM JESD22-A115-A exceeds 200 V Specified from 40 Cto+85 C and from 40 Cto+125 C 3. Ordering information Table 1. Ordering information Type number Package Temperature range Name Description Version 74HCT221D 40 C to +125 C SO16 plastic small outline package 16 leads body width 3.9 mm SOT109-174HCT221 Nexperia Dual non-retriggerable monostable multivibrator with reset 4. Functional diagram 7 &( 7 & 5( ( 7 6 4 4 7 4 4 % 5 7 &( 7 & 5( ( 7 6 4 4 7 4 4 % 5 DDD Fig 1. Functional diagram 5& ( 7& ( 7& 5 ( 7 &( 75 ( 7 &( 75 6 4 5& 7 4 % 5 5 5 DDD DDD Fig 2. Logic symbol Fig 3. IEC logic symbol 74HCT221 All information provided in this document is subject to legal disclaimers. Nexperia B.V. 2017. All rights reserved Product data sheet Rev. 3 26 October 2016 2 of 19 5 4 % 4 4 4 & & 5 5