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Nexperia USA Inc. 74HCT240DB,118
- Part No.:
- 74HCT240DB,118
- Manufacturer:
- Nexperia USA Inc.
- Package:
- 20-SSOP (0.209", 5.30mm Width)
- Datasheet:
-
74HCT240DB,118.pdf
- Description:
- IC BUFFER INVERT 5.5V 20SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:4,386
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Product details
Overview
74HCT240DB,118 from Nexperia is an octal inverting 3-state buffer/line driver with dual output enables (1OE, 2OE), TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 5 V), ±6 mA output drive, and SO20 (SOT163-1) package. It operates from 4.5 V to 5.5 V and supports industrial temperature range (−40 °C to +125 °C), commonly used for bidirectional bus isolation in microcontroller peripheral interfaces.
For engineers reviewing the 74HCT240DB,118 datasheet, 74HCT240DB,118 pinout, 74HCT240DB,118 application, or 74HCT240DB,118 equivalent, key selection criteria include TTL-level input compatibility, dual independent 4-bit 3-state control, propagation delay ≤20 ns (VCC = 4.5 V, CL = 15 pF), enable/disable timing under 45 ns, and SO20 thermal performance with 12.3 mW/K derating above 109 °C.
Technical Context
This device implements two independent 4-bit inverting buffers, each controlled by its own active-low output enable (1OE for Y0–Y3, 2OE for Y4–Y7). Inputs feature clamp diodes enabling safe interfacing to voltages exceeding VCC when current-limiting resistors are used.
It delivers rail-to-rail CMOS output swing with VOH ≥ 3.7 V and VOL ≤ 0.4 V at IO = ±6 mA and VCC = 4.5 V, while maintaining low ICC (≤160 μA at −40 °C to +125 °C) and high noise immunity (Δt/ΔV ≥ 139 ns/V at VCC = 4.5 V).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Function | Inverting octal buffer with dual 3-state control (1OE/2OE) |
| Supply Voltage | 4.5 V to 5.5 V - matches standard 5 V TTL systems without level shifting |
| Input Thresholds | VIH = 2.0 V min, VIL = 0.8 V max - ensures reliable recognition of legacy TTL logic levels |
| Output Drive | ±6 mA at VCC = 4.5 V - sufficient to drive 50 Ω transmission lines or multiple CMOS inputs |
| Propagation Delay | 9 ns typ (VCC = 5.0 V, CL = 15 pF) - supports >20 MHz bus toggle rates |
| Enable/Disable Time | 13–38 ns (−40 °C to +125 °C) - enables precise timing control in shared-bus arbitration |
| Operating Temperature | −40 °C to +125 °C - qualified for under-hood and industrial control environments |
Pinout & Package
74HCT240DB,118 uses the SO20 (SOT163-1) plastic small outline package: 20-pin, 7.5 mm body width, 1.27 mm pitch, gull-wing leads. Thermal resistance θJA = 82 K/W; total power dissipation derates linearly at 12.3 mW/K above 109 °C.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 19 | 1OE, 2OE | Active-low enables for Group 1 (Y0–Y3) and Group 2 (Y4–Y7) outputs |
| 2, 4, 6, 8 | 1A0–1A3 | Inverting input group for first 4-bit buffer section |
| 3, 5, 7, 9 | 2Y0–2Y3 | Inverting 3-state outputs for second 4-bit buffer section |
| 10 | GND | Reference ground plane for all I/O and supply return paths |
| 11, 13, 15, 17 | 2A0–2A3 | Inverting input group for second 4-bit buffer section |
| 12, 14, 16, 18 | 1Y0–1Y3 | Inverting 3-state outputs for first 4-bit buffer section |
| 20 | VCC | Positive supply rail (4.5–5.5 V); decoupling capacitor required at pin |
Key Features
| Feature | Design Value |
|---|---|
| TTL-compatible inputs | VIH/VIL thresholds match legacy 5 V TTL families, eliminating need for level translators |
| Dual independent 3-state control | 1OE and 2OE allow concurrent or staggered bus access for two peripheral groups |
| Input clamp diodes | Enable safe overvoltage tolerance up to VCC + 0.5 V with external current limiting |
| High ESD robustness | HBM > 2000 V, CDM > 1000 V - reduces handling sensitivity and board-level failure risk |
| Wide temp range support | Specified from −40 °C to +125 °C - suitable for automotive engine control and industrial PLC modules |
Applications
| Microcontroller Bus Isolation | Industrial I/O Expansion |
|---|---|
|
Use Scenario: Isolating a 5 V microcontroller's address/data bus from multiple peripheral ICs sharing the same lines. IC Role / Device Role: Inverting 3-state buffer providing direction-controlled signal pass-through and high-impedance bus release during idle cycles. Use Value: Prevents bus contention during multi-peripheral read/write sequences while maintaining TTL-level compatibility with legacy peripherals. |
Use Scenario: Expanding digital I/O capacity on a programmable logic controller (PLC) backplane using daisy-chained modules. IC Role / Device Role: Bidirectional line driver buffering sensor input signals and actuator control outputs across noisy industrial backplanes. Use Value: Enables clean signal integrity over 20 cm traces at 10 MHz with ±6 mA drive strength and 0.4 V VOL guarantee. |
| Legacy System Interface Adapter | Test Equipment Signal Conditioning |
|
Use Scenario: Interfacing modern FPGA-based test hardware to vintage 5 V TTL instrumentation with strict voltage threshold requirements. IC Role / Device Role: Level-shifting and bus-driving interface translating between FPGA I/O banks and TTL logic thresholds. Use Value: Eliminates external resistor networks by meeting VIH = 2.0 V and VIL = 0.8 V directly, reducing BOM count and layout area. |
Use Scenario: Driving calibrated reference signals into high-capacitance DUT inputs during automated functional testing. IC Role / Device Role: Low-skew, inverting buffer delivering precise timing edges with <15 ns transition time (tt) and matched enable/disable delays. Use Value: Ensures sub-nanosecond edge alignment across 8 channels for synchronized stimulus generation in ATE platforms. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal inverting 3-state buffer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74HCT240N | DIP-20 package; higher θJA (100 K/W); no SO20 footprint compatibility | Suitable for prototyping or through-hole production; not drop-in for surface-mount boards | Select only if manual assembly or socket-based validation is required. |
| 74HCT240PW,118 | TSSOP20 (SOT360-1); 4.4 mm width; 10.0 mW/K derating above 100 °C; identical electrical specs | Better PCB space efficiency and thermal performance in dense layouts | Prefer for high-density industrial control boards where SO20 footprint is unavailable. |
Compared with SN74HCT240N and 74HCT240PW,118, the 74HCT240DB,118 offers optimal thermal reliability in reflow-soldered SO20 designs, while maintaining full functional and timing equivalence - making it the preferred choice for volume automotive and industrial surface-mount applications requiring proven long-term solder joint integrity.
Availability
74HCT240DB,118 is available at Aetrix Electronics and suitable for microcontroller bus isolation, industrial I/O expansion, legacy system interface adapters, and test equipment signal conditioning requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for 74HCT240DB,118 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Nexperia is a leading global semiconductor expert focused on essential semiconductors for efficient energy use and reliable performance in automotive, industrial, and consumer applications.
The 74HCT240DB,118 belongs to Nexperia's 74HCT logic family, engineered specifically for robust interoperability with legacy TTL systems while delivering CMOS power efficiency and noise immunity in industrial-grade packages.
FAQ
What is the maximum clock frequency this device supports?
The 74HCT240DB,118 does not operate as a clocked device but as a combinatorial buffer. Its usable signal toggle rate is determined by propagation delay (9 ns typ at VCC = 5 V, CL = 15 pF) and transition time (5–12 ns). This supports reliable operation up to approximately 20 MHz on well-terminated buses with minimal skew across all eight channels.
Can 1OE and 2OE be tied together for single-enable operation?
Yes - connecting 1OE and 2OE to a common control signal is electrically valid and commonly implemented to simplify logic control. Doing so converts the device into a unified 8-bit 3-state buffer. No additional components or timing penalties are incurred, as both enables share identical DC and AC specifications per datasheet Table 5 and Figure 3.
Is this part qualified for automotive applications?
No - the 74HCT240DB,118 is specified for industrial temperature range (−40 °C to +125 °C) but is not AEC-Q100 qualified. Nexperia explicitly states in Section 14 that non-automotive qualified products are unsuitable for safety-critical or life-support systems. For automotive use, consult Nexperia's AEC-Q100-certified 74HCT240 variants such as 74HCT240BQ-Q100.
What is the recommended PCB layout practice for VCC and GND pins?
Place a 100 nF ceramic decoupling capacitor between Pin 20 (VCC) and Pin 10 (GND), located within 3 mm of the SO20 package. Use dedicated 0.3 mm wide power and ground traces routed directly to the capacitor pads, avoiding shared vias or daisy-chained connections. This minimizes high-frequency supply impedance and prevents output switching noise from coupling into adjacent channels.
74HCT240DB,118 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- 74HCT
- Package/Case:
- 20-SSOP (0.209", 5.30mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Logic Type:
- Buffer, Inverting
- Number of Elements:
- 2
- Number of Bits per Element:
- 4
- Input Type:
- -
- Output Type:
- 3-State
- Current - Output High, Low:
- 6mA, 6mA
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SSOP
74HCT240DB,118 FAQ
1.How can I place an order for 74HCT240DB,118 through Aetrix?
Please submit a Request for Quotation (RFQ) for 74HCT240DB,118 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for 74HCT240DB,118 reliable?
The price and inventory of 74HCT240DB,118 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 74HCT240DB,118 is usually 5 days.
3.What payment methods are accepted for 74HCT240DB,118?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 74HCT240DB,118 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 74HCT240DB,118?
74HCT240DB,118 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 74HCT240DB,118 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for 74HCT240DB,118?
For technical support, including 74HCT240DB,118 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 74HCT240DB,118 requirements.
6.How does Aetrix verify that 74HCT240DB,118 is sourced from the original manufacturer or authorized distributors?
All 74HCT240DB,118 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that 74HCT240DB,118 meets industry standards.
7.What is the process for return or replacement of 74HCT240DB,118?
All 74HCT240DB,118 units undergo pre-shipment inspection (PSI). If there is an issue with 74HCT240DB,118, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The 74HCT240DB,118 part is unused and in its original packaging.
Return procedure for 74HCT240DB,118:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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