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Click here for more information74HCT4538DB
Dual retriggerable precision monostable multivibrator
The 74HCT4538 is a dual retriggerable-resettable monostable multivibrator. Each multivibrator has two trigger/retrigger inputs (nA and nB), a direct reset input (nCD), two complementary outputs (nQ and nQ), and two pins (nREXT/CEXT and nCEXT) for connecting the external timing components 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 components 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 nCD 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.
Alternatives
Features and benefits
Tolerant of slow trigger rise and fall times
High noise immunity
Separate reset inputs
Triggering from falling or rising edge
Complies 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 mA per JESD 78 Class II Level B
ESD protection:
HBM: ANSI/ESDA/JEDEC JS-001 class 2 exceeds 2000 V
CDM: ANSI/ESDA/JEDEC JS-002 class C3 exceeds 1000 V
Specified from -40 °C to +85 °C and from -40 °C to +125 °C
PCB Symbol, Footprint and 3D Model
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Package
All type numbers in the table below are discontinued.
| Type number | Orderable part number, (Ordering code (12NC)) | Status | Marking | Package | Package information | Reflow-/Wave soldering | Packing |
|---|---|---|---|---|---|---|---|
| 74HCT4538DB | 74HCT4538DB,112 (935188780112) |
Obsolete | no package information | ||||
| 74HCT4538DB,118 (935188780118) |
Obsolete | ||||||
Environmental information
All type numbers in the table below are discontinued.
| Type number | Orderable part number | Chemical content | RoHS | RHF-indicator |
|---|---|---|---|---|
| 74HCT4538DB | 74HCT4538DB,112 | 74HCT4538DB |
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| 74HCT4538DB | 74HCT4538DB,118 | 74HCT4538DB |
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Documentation (3)
| File name | Title | Type | Date |
|---|---|---|---|
| AN11044 | Pin FMEA 74HC/74HCT family | Application note | 2019-01-09 |
| hc | HC/HCT Spice model | SPICE model | 2022-02-17 |
| HCT_USER_GUIDE | HC/T User Guide | User manual | 1997-10-31 |
Support
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Models
| File name | Title | Type | Date |
|---|---|---|---|
| hc | HC/HCT Spice model | SPICE model | 2022-02-17 |
PCB Symbol, Footprint and 3D Model
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How does it work?
The interactive datasheets are based on the Nexperia MOSFET precision electrothermal models. With our interactive datasheets you can simply specify your own conditions interactively. Start by changing the values of the conditions. You can do this by using the sliders in the condition fields. By dragging the sliders you will see how the MOSFET will perform at the new conditions set.