My Inquiry
My Account
onsemi MC74AC240DWG
- Part No.:
- MC74AC240DWG
- Manufacturer:
- onsemi
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
MC74AC240DWG.pdf
- Description:
- IC BUFF INVERT 6V 20SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,042
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MC74AC240DWG from onsemi is an octal 3-state buffer/line driver designed for memory address driving, clock distribution, and bidirectional bus interfacing in high-density PCBs. It operates from 2.0 V to 6.0 V, delivers ±24 mA output drive, features TTL-compatible inputs only in the ACT variant (not this AC version), and supports industrial temperature range (−40°C to +85°C).
For engineers reviewing the MC74AC240DWG datasheet, pinout, applications, or equivalent options, key selection criteria include supply voltage compatibility (2.0–6.0 V), 3-state enable timing (tPZH/tPLZ ≤ 11.5 ns at 5 V), output drive strength (±24 mA), input threshold levels (VIH = 2.1 V min @ 3 V), and SOIC-20W package thermal resistance (96 °C/W).
Technical Context
The MC74AC240DWG implements eight independent non-inverting buffers, each with dual 3-state enable controls (OE1 on pins 12/14/16/18; OE2 on pins 3/5/7/9). Its CMOS AC logic family ensures low static power consumption (ICC ≤ 80 µA) while maintaining fast propagation delays (tPLH/tPHL ≤ 7.0 ns typical at 5 V, CL = 50 pF).
All outputs exhibit rail-to-rail swing capability (VOH ≥ 4.4 V, VOL ≤ 0.44 V at IOL = 24 mA, VCC = 5.5 V) and high noise immunity (VIH = 2.1 V min @ VCC = 3.0 V; VIL = 0.9 V max). Input leakage (IIN ≤ ±1.0 µA) and 3-state off-state current (IOZ ≤ ±5.0 µA) are specified across full temperature range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 2.0 V to 6.0 V - supports mixed-voltage system interfacing and legacy 5 V designs |
| Output Drive | ±24 mA - sufficient to drive standard TTL loads or 50 pF transmission lines without external buffering |
| Propagation Delay | ≤ 7.0 ns (tPLH/tPHL, VCC = 5.0 V, CL = 50 pF) - enables reliable operation in sub-100 MHz bus timing budgets |
| 3-State Enable Time | tPZH ≤ 8.0 ns, tPZL ≤ 8.5 ns (VCC = 5.0 V) - critical for glitch-free bus arbitration in shared-data-path systems |
| Input Thresholds | VIH = 2.1 V min @ 3.0 V; VIL = 0.9 V max @ 3.0 V - provides 1.2 V noise margin under nominal 3 V supply |
| Operating Temperature | −40°C to +85°C - qualified for industrial-grade embedded control and instrumentation applications |
| Package Thermal RθJA | 96 °C/W (SOIC-20W) - allows sustained 8-output switching at up to 50 mW total dissipation without forced cooling |
Pinout & Package
MC74AC240DWG uses a 20-lead SOIC Wide Body (SOIC-20W, Case 751D) package with 1.27 mm pitch, 12.8 mm × 7.5 mm body size, and Pb-free finish (G suffix). Pin 1 is located at top-left corner (notch-marked end), with VCC (pin 20) and GND (pin 10) placed diagonally opposite for optimal decoupling layout.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 4, 6, 11, 13, 15, 17 | Buffer Inputs (A1–A8) | Non-inverting data inputs; accept CMOS-level signals across full VCC range |
| 19, 18, 16, 14, 12, 9, 7, 5 | Buffer Outputs (Y1–Y8) | 3-state outputs; high-impedance when either OE1 or OE2 is HIGH |
| 12, 14, 16, 18 | OE1 (Group 1 Enable) | Active-LOW enable for outputs Y1–Y4; shared control simplifies bus direction logic |
| 3, 5, 7, 9 | OE2 (Group 2 Enable) | Active-LOW enable for outputs Y5–Y8; independent group control enables split-bus architectures |
| 20 | VCC | Positive supply (2.0–6.0 V); requires local 0.1 µF ceramic decoupling adjacent to pin |
| 10 | GND | Ground reference; connects to PCB ground plane for signal integrity and thermal conduction |
Key Features
| Feature | Design Value |
|---|---|
| Octal 3-state buffering | Two independent enable groups (OE1/OE2) allow selective activation of Y1–Y4 or Y5–Y8, enabling flexible bus segmentation |
| High-output drive (±24 mA) | Eliminates need for external line drivers in memory address or control bus applications with up to 10 TTL loads |
| Low quiescent ICC (≤ 80 µA) | Reduces standby power in battery-backed or energy-sensitive systems without sacrificing speed |
| Rail-to-rail VOH/VOL | Ensures robust logic level translation between 3.3 V and 5 V domains when used with appropriate VCC |
| Pb-free SOIC-20W package | Complies with RoHS Directive 2011/65/EU and JEDEC J-STD-020 moisture sensitivity Level 1 handling |
Applications
| Memory Address Buffering | Microcontroller Bus Interface |
|---|---|
|
Use Scenario: Driving 16-bit address lines from a microcontroller to multiple SRAM or Flash devices on a shared bus. IC Role / Device Role / Timing Role: Non-inverting buffer with grouped 3-state control isolates address lines during memory read/write cycles. Use Value: Prevents bus contention and reduces trace loading; ±24 mA drive ensures setup/hold timing margins at 20 MHz address strobe rates. |
Use Scenario: Interfacing an 8-bit MCU's parallel port to external peripherals requiring separate read/write strobes and data latching. IC Role / Device Role / Timing Role: Bidirectional bus transceiver substitute using OE1/OE2 to control direction per nibble group. Use Value: Enables half-duplex data exchange without dedicated transceivers; tPZH ≤ 8 ns guarantees clean enable timing relative to WR# assertion. |
| Industrial PLC I/O Expansion | Legacy System Clock Distribution |
|
Use Scenario: Expanding digital I/O capacity in programmable logic controllers by buffering GPIO signals to isolated relay or optocoupler driver stages. IC Role / Device Role / Timing Role: Level-shifting buffer translating 3.3 V MCU outputs to 5 V tolerant input stages of industrial interface ICs. Use Value: VIH = 2.1 V min @ 3 V ensures reliable recognition of low-voltage logic; 85°C rating supports enclosure-mounted operation. |
Use Scenario: Distributing a master system clock to multiple synchronous peripherals (e.g., ADCs, DACs, FPGAs) with matched skew requirements. IC Role / Device Role / Timing Role: Low-skew, fanout-8 clock driver with simultaneous edge delivery across all eight outputs. Use Value: Propagation delay matching ≤ 0.5 ns (typical) minimizes inter-channel skew; low Cpd (45 pF) limits jitter contribution. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal 3-state buffer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74AC240N | Dual in-line package (PDIP-20); higher RθJA (105 °C/W); identical AC electrical specs and pinout | Suitable for prototyping or through-hole assembly; not recommended for high-density or thermally constrained PCBs | Select SN74AC240N only when manual soldering or socket-based validation is required. |
| MC74AC244DWG | Non-inverting octal buffer with single 3-state enable (OE) instead of dual OE1/OE2 grouping | Lacks independent group control; requires external logic to replicate split-enable functionality | Choose MC74AC244DWG only if unified enable suffices and board space permits added gate logic. |
Compared with SN74AC240N and MC74AC244DWG, the MC74AC240DWG uniquely offers dual-group 3-state control in a thermally optimized SOIC-20W package, enabling compact, low-skew bus segmentation without layout or logic overhead.
Availability
MC74AC240DWG is available at Aetrix Electronics and suitable for industrial control systems, memory subsystems, and microcontroller peripheral interfaces requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.
Supply support for MC74AC240DWG 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 silicon solutions for automotive, industrial, cloud, medical, and IoT applications.
The MC74AC240DWG belongs to the 74AC logic family, engineered for high-speed, low-power digital interfacing in space-constrained industrial and computing systems where reliability across extended temperature ranges is essential.
FAQ
What is the maximum supply voltage for MC74AC240DWG?
The MC74AC240DWG supports a DC supply voltage (VCC) range of −0.5 V to +6.5 V, with recommended operation between 2.0 V and 6.0 V. Exceeding 6.5 V risks permanent damage per absolute maximum ratings. At VCC = 6.0 V, VOH remains ≥ 5.4 V and VOL ≤ 0.44 V under 24 mA load, confirming robust rail-to-rail performance within spec.
Does MC74AC240DWG have TTL-compatible inputs?
No, MC74AC240DWG does not have TTL-compatible inputs. That feature applies only to the MC74ACT240 variant. The MC74AC240DWG uses CMOS-compatible input thresholds: VIH = 2.1 V min @ VCC = 3.0 V and VIL = 0.9 V max, which differ from TTL's 2.0 V/0.8 V thresholds. Using it with legacy TTL outputs may require level-shifting verification.
How are the two 3-state enable inputs (OE1 and OE2) configured on MC74AC240DWG?
MC74AC240DWG has two independent active-LOW 3-state enable inputs: OE1 (pins 12, 14, 16, 18) controls outputs Y1–Y4, and OE2 (pins 3, 5, 7, 9) controls outputs Y5–Y8. Both must be LOW for their respective outputs to drive; if either is HIGH, its group enters high-impedance state. This allows partial bus isolation without disabling all eight lines simultaneously.
What is the thermal resistance (RθJA) of MC74AC240DWG in its SOIC-20W package?
The MC74AC240DWG in SOIC-20W (Case 751D) has a junction-to-ambient thermal resistance (RθJA) of 96 °C/W, per JESD 51-7 methodology. This value assumes standard JEDEC 2S2P test board conditions. With typical power dissipation below 50 mW, the junction temperature rise stays under 5 °C above ambient - well within the 140 °C max TJ limit.
Can MC74AC240DWG be used in 3.3 V systems?
Yes, MC74AC240DWG is fully specified for 3.3 V operation (VCC = 3.0 V min, 3.3 V typical). At 3.3 V, VIH = 1.5 V min and VIL = 0.9 V max provide 1.2 V noise margin; tPLH/tPHL ≤ 8.0 ns ensures timing compliance with 3.3 V microcontrollers and FPGAs. Its 2.0–6.0 V range makes it ideal for mixed-voltage board designs.
MC74AC240DWG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- 74AC
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Bulk
- 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:
- 24mA, 24mA
- Voltage - Supply:
- 2V ~ 6V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOIC
MC74AC240DWG FAQ
1.How can I place an order for MC74AC240DWG through Aetrix?
Please submit a Request for Quotation (RFQ) for MC74AC240DWG 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 MC74AC240DWG reliable?
The price and inventory of MC74AC240DWG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MC74AC240DWG is usually 5 days.
3.What payment methods are accepted for MC74AC240DWG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MC74AC240DWG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MC74AC240DWG?
MC74AC240DWG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MC74AC240DWG 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 MC74AC240DWG?
For technical support, including MC74AC240DWG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MC74AC240DWG requirements.
6.How does Aetrix verify that MC74AC240DWG is sourced from the original manufacturer or authorized distributors?
All MC74AC240DWG 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 MC74AC240DWG meets industry standards.
7.What is the process for return or replacement of MC74AC240DWG?
All MC74AC240DWG units undergo pre-shipment inspection (PSI). If there is an issue with MC74AC240DWG, 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 MC74AC240DWG part is unused and in its original packaging.
Return procedure for MC74AC240DWG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MC74AC240DWG Tags
-
SN74LVC1G17DBVR
Texas Instruments
-
SN74LVC1G07DCKR
Texas Instruments
-
SN74LVC1G17DCKR
Texas Instruments
-
SN74LVC1G07DBVR
Texas Instruments
-
SN74LVC1G125DCKR
Texas Instruments
-
SN74AHCT1G126DBVR
Texas Instruments
-
SN74LVC1G125DBVR
Texas Instruments
-
SN74AHCT1G125DBVR
Texas Instruments
-
SN74LVC2G17DBVR
Texas Instruments
-
SN74LVC2G07DCKR
Texas Instruments
-
SN74LVC1G34DCKR
Texas Instruments
-
SN74LVC2G17DCKR
Texas Instruments
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
