74HCT4538 Datasheet | Nexperia

description The 74HCT4538 is a dual retriggerable-resettable monostable multivibrator. Each multivibrator has two trigger/retrigger inputs (n A and n B), a direct reset input (n CD), two plementary outputs (n Q and n Q), and two pins (n REXT/CEXT and n CEXT) for connecting the external timing ponents CEXT and REXT. Typical pulse width variation over temperature range is ± 0.2 %. The device may be triggered by either the positive or the negative edges of the input pulse. The duration and accuracy of the output pulse are determined by the external timing ponents CEXT and REXT. The output pulse width (TW) is equal to 0.7 × REXT × CEXT. The linear design techniques guarantee precise control of the output pulse width. A LOW level at n CD terminates the output pulse immediately. Schmitt-trigger action in the trigger inputs makes the circuit highly tolerant to slower rise and fall times. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC. 2. Features and benefits - Tolerant of slow trigger rise and fall times - High noise immunity - Separate reset inputs - Triggering from falling or rising edge - plies with JEDEC standard no. 7A - Wide supply voltage range from 4.5 to 5.5 V - CMOS low power dissipation - TTL input levels - Latch-up performance exceeds 100 m A per JESD 78 Class II Level B - ESD protection: - HBM JESD22-A114F exceeds 2000 V - MM JESD22-A115-A exceeds 200 V - Specified from -40 °C to +85 °C and from -40 °C to +125 °C 3. Ordering information Table 1. Ordering information Type number Package Temperature range Name Description Version 74HCT4538D -40 °C to +125 °C SO16 plastic small outline package; 16 leads; body width 3.9 mm SOT109-1 74HCT4538PW -40 °C to +125 °C TSSOP16 plastic thin shrink small outline package; 16 leads; body width 4.4 mm SOT403-1 Nexperia 4. Functional diagram Fig. 1. Functional diagram n B n A Dual retriggerable precision monostable multivibrator 2...