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onsemi MC74HC240AFG
- Part No.:
- MC74HC240AFG
- Manufacturer:
- onsemi
- Package:
- 20-SOIC (0.209", 5.30mm Width)
- Datasheet:
-
MC74HC240AFG.pdf
- Description:
- IC BUFFER INVERT 6V SOEIAJ-20
- Quantity:
- Payment:
- Shipping:
Inventory:4,855
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Product details
Overview
MC74HC240AFG from onsemi is an octal 3-state inverting buffer/line driver with dual active-low output enables, operating across 2.0–6.0 V supply, delivering ±7.8 mA output drive at 6 V, and supporting industrial temperature range (–55°C to +125°C) in SOIC-20 wide-body package. It interfaces memory address buses and clock distribution networks in embedded control systems.
For engineers reviewing the MC74HC240AFG datasheet, pinout, applications, or equivalent options, key selection criteria include its inverting logic function, dual independent 3-state control, LSTTL-compatible drive strength (15 loads), CMOS/NMOS/TTL interoperability, and AEC-Q100 qualified automotive variant availability.
Technical Context
The MC74HC240AFG implements eight independent inverting buffers grouped into two 4-bit banks (A and B), each controlled by a dedicated active-low enable (Enable A on Pin 1, Enable B on Pin 19). Outputs enter high-impedance state when respective enable is high, enabling bus sharing without external isolation.
Its silicon-gate CMOS process ensures low input current (±0.1 µA max at 6 V), high noise immunity, and compatibility with both standard CMOS outputs and LSTTL outputs (with pullup resistors). Propagation delay is 14 ns typical at VCC = 6 V, with output transition time ≤15 ns.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Function | Octal inverting buffer with dual 3-state control - enables bidirectional bus arbitration via two independent enable inputs. |
| Supply Voltage Range | 2.0 V to 6.0 V - supports mixed-voltage system interfacing (e.g., 3.3 V logic driving 5 V peripherals). |
| Output Drive Strength | ±7.8 mA at VCC = 6 V - drives up to 15 LSTTL loads, sufficient for legacy TTL bus loading without buffering. |
| Propagation Delay | 14 ns max (tPLH/tPHL at VCC = 6 V) - ensures timing-critical address/data path integrity in microcontroller peripheral expansion. |
| Operating Temperature | –55°C to +125°C - validated for under-hood automotive and industrial control environments. |
| Input Leakage Current | ±0.1 µA max at VCC = 6 V - minimizes standby power and prevents unintended logic transitions on unterminated lines. |
| 3-State Leakage | ±0.5 µA max at VCC = 6 V - maintains clean bus float during disable, reducing crosstalk in shared data paths. |
Pinout & Package
MC74HC240AFG is housed in SOIC-20 wide-body package (Case 751D), 12.8 mm × 7.5 mm footprint, 2.65 mm max height, with 1.27 mm pitch and Pb-free (G-suffix) finish.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 19 | Enable A / Enable B | Active-low enables for A-group (YA1–YA4) and B-group (YB1–YB4); independent control allows interleaved bus access. |
| 2, 4, 6, 8 | A1–A4 Inputs | Data inputs for first inverting bank; inverted outputs appear on YA1–YA4 when Enable A = LOW. |
| 11, 13, 15, 17 | B1–B4 Inputs | Data inputs for second inverting bank; inverted outputs appear on YB1–YB4 when Enable B = LOW. |
| 18, 16, 14, 12 | YA1–YA4 Outputs | Inverted outputs of A-group; high-impedance when Enable A = HIGH - isolates A-bus from downstream circuitry. |
| 9, 7, 5, 3 | YB1–YB4 Outputs | Inverted outputs of B-group; high-impedance when Enable B = HIGH - enables time-multiplexed B-bus usage. |
| 20 | VCC | Positive supply rail (2.0–6.0 V); decoupling capacitor required within 10 mm for stable switching performance. |
| 10 | GND | Ground reference for all I/O and supply; must be low-inductance connection to minimize ground bounce. |
Key Features
| Feature | Design Value |
|---|---|
| 3-State Output Control | Dual independent active-low enables allow simultaneous or staggered bus release, eliminating contention in multi-master systems. |
| LSTTL Load Compatibility | Drives 15 LSTTL loads directly - eliminates need for level-shifting buffers in legacy industrial backplane designs. |
| Wide Supply Range | 2.0–6.0 V operation enables single device deployment across 3.3 V microcontrollers and 5 V peripheral subsystems. |
| High Noise Immunity | CMOS input threshold ratios (VIH ≥ 70% VCC, VIL ≤ 30% VCC) reject >400 mV of coupled noise on PCB traces. |
| AEC-Q100 Qualified Variant | MC74HC240ADWR2G−Q offers automotive-grade qualification (Grade 1), PPAP support, and controlled change management. |
Applications
| Industrial PLC Backplane Interface | Automotive Body Control Module |
|---|---|
|
Use Scenario: Interfacing microcontroller GPIOs to legacy 5 V address/data buses in programmable logic controller rack modules. IC Role / Device Role / Timing Role: Inverting 3-state buffer providing voltage-level translation and bus contention protection between 3.3 V MCU and 5 V peripheral cards. Use Value: Eliminates discrete level shifters and reduces board space by 40% versus dual-buffer solutions while maintaining <15 ns timing margin. |
Use Scenario: Driving multiplexed sensor readout lines (e.g., door lock status, window position) in body control units with shared diagnostic bus. IC Role / Device Role / Timing Role: Dual-bank inverting driver enabling time-sliced polling of multiple sensors over common signal lines without hardware reconfiguration. Use Value: Reduces wiring harness count by consolidating 8 sensor signals into 4 shared lines, lowering EMI and assembly cost. |
| Test Equipment Signal Conditioning | Medical Diagnostic Data Acquisition |
|
Use Scenario: Isolating FPGA I/O banks from variable-impedance test fixtures during automated functional testing of PCBAs. IC Role / Device Role / Timing Role: High-impedance buffer stage preventing fixture-induced signal reflection and ensuring clean edge integrity at 50 MHz toggle rates. Use Value: Improves test repeatability by suppressing false fails caused by 100+ pF fixture capacitance loading. |
Use Scenario: Buffering analog front-end multiplexer control signals in portable ultrasound devices where EMI immunity is critical. IC Role / Device Role / Timing Role: Low-noise inverting driver delivering glitch-free channel selection timing to precision ADC multiplexers. Use Value: Prevents 12-bit ADC code errors by eliminating >10 ns enable skew between multiplexer banks. |
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 |
|---|---|---|---|
| SN74HC240N | Identical logic function and pinout; TI version uses SOIC-20 narrow-body (Case 751A), 12.8 mm × 7.5 mm but 2.35 mm height vs. onsemi's 2.65 mm. | Same industrial temperature range (–40°C to +85°C only); not AEC-Q100 qualified. | Select SN74HC240N only if board layout accommodates tighter height clearance and automotive qualification is unnecessary. |
| 74VHC240M | Higher speed: 7.5 ns max propagation delay at 5 V; lower drive (±8 mA), identical 2–5.5 V supply range. | Optimized for high-frequency data acquisition; lacks –55°C rating and AEC-Q100 option. | Choose 74VHC240M when sub-10 ns timing is mandatory and extended temperature operation is not required. |
Compared with SN74HC240N and 74VHC240M, the MC74HC240AFG provides broader temperature coverage (–55°C to +125°C), AEC-Q100 automotive variants, and guaranteed 14 ns max delay at 6 V - making it the preferred choice for mission-critical industrial and automotive control applications requiring long-term reliability validation.
Availability
MC74HC240AFG is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive body control modules, and medical diagnostic data acquisition systems requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for MC74HC240AFG 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The MC74HC240AFG belongs to onsemi's HC logic family, designed for robust, low-power interfacing in harsh-environment embedded systems where reliability, wide voltage operation, and noise immunity are essential.
FAQ
What is the maximum operating temperature for MC74HC240AFG?
The MC74HC240AFG is rated for operation from –55°C to +125°C across all package variants. This full industrial temperature range is verified per JEDEC JESD22-A108 and applies to both standard and automotive-qualified versions (e.g., MC74HC240ADWR2G−Q), ensuring reliable performance in engine bay or factory-floor environments where ambient heat exceeds 100°C.
Does MC74HC240AFG support 3.3 V logic levels?
Yes, MC74HC240AFG fully supports 3.3 V operation: its guaranteed VIH is 2.1 V and VIL is 0.9 V at VCC = 3.0 V, providing >1.2 V noise margin against 3.3 V CMOS outputs. Input thresholds scale with supply voltage, ensuring robust recognition of 3.3 V logic highs and lows without external biasing.
Can MC74HC240AFG replace LS240 in existing designs?
Yes, MC74HC240AFG is explicitly designed as a pinout-identical replacement for 74LS240, with compatible input thresholds (when pulled up) and output drive capability sufficient for 15 LSTTL loads. No PCB changes are required, though decoupling and layout practices should follow CMOS guidelines to avoid ringing.
What is the meaning of the 'FG' suffix in MC74HC240AFG?
The 'FG' suffix in MC74HC240AFG indicates a Pb-free, halogen-free SOIC-20 wide-body package (Case 751D) compliant with RoHS Directive 2011/65/EU. It corresponds to onsemi's standard commercial-grade offering - distinct from 'Q' suffix variants which add AEC-Q100 qualification and PPAP documentation.
How does the dual-enable architecture of MC74HC240AFG improve system design?
The dual active-low enables (Enable A and Enable B) in MC74HC240AFG allow independent control of two 4-bit inverting banks, enabling time-multiplexed bus access, reduced signal contention, and simplified arbitration logic. This eliminates the need for external gating logic or additional buffers when managing split data/address paths in microcontroller peripheral expansion.
MC74HC240AFG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- 74HC
- Package/Case:
- 20-SOIC (0.209", 5.30mm Width)
- Packaging:
- Tube
- 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:
- 7.8mA, 7.8mA
- Voltage - Supply:
- 2V ~ 6V
- Operating Temperature:
- -55°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOEIAJ-20
MC74HC240AFG FAQ
1.How can I place an order for MC74HC240AFG through Aetrix?
Please submit a Request for Quotation (RFQ) for MC74HC240AFG 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 MC74HC240AFG reliable?
The price and inventory of MC74HC240AFG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MC74HC240AFG is usually 5 days.
3.What payment methods are accepted for MC74HC240AFG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MC74HC240AFG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MC74HC240AFG?
MC74HC240AFG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MC74HC240AFG 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 MC74HC240AFG?
For technical support, including MC74HC240AFG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MC74HC240AFG requirements.
6.How does Aetrix verify that MC74HC240AFG is sourced from the original manufacturer or authorized distributors?
All MC74HC240AFG 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 MC74HC240AFG meets industry standards.
7.What is the process for return or replacement of MC74HC240AFG?
All MC74HC240AFG units undergo pre-shipment inspection (PSI). If there is an issue with MC74HC240AFG, 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 MC74HC240AFG part is unused and in its original packaging.
Return procedure for MC74HC240AFG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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