Orderable parts
| Type number | Orderable part number | Ordering code (12NC) | Package | Buy from distributors |
|---|---|---|---|---|
| 74HCT138BQ | 74HCT138BQ,115 | 935274471115 | SOT763-1 | Order product |
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Click here for more information74HCT138BQ
3-to-8 line decoder/demultiplexer; inverting
The 74HC138; 74HCT138 decodes three binary weighted address inputs (A0, A1 and A2) to eight mutually exclusive outputs (Y0 to Y7). The device features three enable inputs (E1, E2 and E3). Every output will be HIGH unless E1 and E2 are LOW and E3 is HIGH. This multiple enable function allows easy parallel expansion to a 1-of-32 (5 to 32 lines) decoder with just four '138 ICs and one inverter. The '138 can be used as an eight output demultiplexer by using one of the active LOW enable inputs as the data input and the remaining enable inputs as strobes. 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
Wide supply voltage range from 2.0 to 6.0 V
CMOS low power dissipation
High noise immunity
Latch-up performance exceeds 100 mA per JESD 78 Class II Level B
Demultiplexing capability
Multiple input enable for easy expansion
Ideal for memory chip select decoding
Active LOW mutually exclusive outputs
Input levels:
For 74HC138: CMOS level
For 74HCT138: TTL level
Complies with JEDEC standards:
JESD8C (2.7 V to 3.6 V)
JESD7A (2.0 V to 6.0 V)
ESD protection:
HBM: ANSI/ESDA/JEDEC JS-001 class 2 exceeds 2000 V
CDM: ANSI/ESDA/JEDEC JS-002 class C3 exceeds 1000 V
Multiple package options
Specified from -40 °C to +85 °C and from -40 °C to +125 °C
Parametrics
| Type number | VCC (V) | Logic switching levels | Output drive capability (mA) | tpd (ns) | Power dissipation considerations | Tamb (°C) | Rth(j-a) (K/W) | Ψth(j-top) (K/W) | Rth(j-c) (K/W) | Package name |
|---|---|---|---|---|---|---|---|---|---|---|
| 74HCT138BQ | 4.5 - 5.5 | TTL | ± 4 | 19 | low | -40~125 | 93 | 14.3 | 63 | DHVQFN16 |
PCB Symbol, Footprint and 3D Model
| Model Name | Description |
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Package
| Type number | Orderable part number, (Ordering code (12NC)) | Status | Marking | Package | Package information | Reflow-/Wave soldering | Packing |
|---|---|---|---|---|---|---|---|
| 74HCT138BQ | 74HCT138BQ,115 (935274471115) |
Active | HCT138 |
DHVQFN16 (SOT763-1) |
SOT763-1 | SOT763-1_115 |
Environmental information
| Type number | Orderable part number | Chemical content | RoHS | RHF-indicator |
|---|---|---|---|---|
| 74HCT138BQ | 74HCT138BQ,115 | 74HCT138BQ |
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Series
Documentation (11)
| File name | Title | Type | Date |
|---|---|---|---|
| 74HC_HCT138 | 3-to-8 line decoder/demultiplexer; inverting | Data sheet | 2024-02-26 |
| AN11044 | Pin FMEA 74HC/74HCT family | Application note | 2019-01-09 |
| AN90063 | Questions about package outline drawings | Application note | 2025-06-13 |
| SOT763-1 | 3D model for products with SOT763-1 package | Design support | 2019-10-03 |
| Nexperia_package_poster | Nexperia package poster | Leaflet | 2020-05-15 |
| DHVQFN16_SOT763-1_mk | plastic, dual in-line compatible thermal enhanced very thin quad flat package; 16 terminals; 0.5 mm pitch; 3.5 mm x 2.5 mm x 0.85 mm body | Marcom graphics | 2017-01-28 |
| SOT763-1 | plastic, leadless dual in-line compatible thermal enhanced very thin quad flat package; 16 terminals; 0.5 mm pitch; 3.5 mm x 2.5 mm x 1 mm body | Package information | 2023-05-11 |
| SOT763-1_115 | DHVQFN16; Reel pack, SMD, 7" Q1/T1 product orientation | Packing information | 2020-04-21 |
| 74HCT138BQ_Nexperia_Product_Reliability | 74HCT138BQ Nexperia Product Reliability | Quality document | 2025-03-20 |
| 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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Longevity
The Nexperia Longevity Program is aimed to provide our customers information from time to time about the expected time that our products can be ordered. The NLP is reviewed and updated regularly by our Executive Management Team. View our longevity program here.
PCB Symbol, Footprint and 3D Model
| Model Name | Description |
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Ordering, pricing & availability
| Type number | Orderable part number | Ordering code (12NC) | Status | Packing | Packing Quantity | Buy online |
|---|---|---|---|---|---|---|
| 74HCT138BQ | 74HCT138BQ,115 | 935274471115 | Active | SOT763-1_115 | 3,000 |
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Sample
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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.