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onsemi 74LVTH240SJX
- Part No.:
- 74LVTH240SJX
- Manufacturer:
- onsemi
- Package:
- 20-SOIC (0.209", 5.30mm Width)
- Datasheet:
-
74LVTH240SJX.pdf
- Description:
- IC BUFFER INVERT 3.6V 20SOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,911
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Product details
Overview
74LVTH240SJX from Fairchild Semiconductor is an inverting octal buffer/line driver with 3-STATE outputs, designed for low-voltage (3.3 V) bus interfacing while maintaining TTL compatibility with 5 V systems. It features bushold inputs eliminating external pull-ups, ±32 mA/64 mA output drive, and operates across –40 °C to +85 °C. It is used in memory address drivers, clock distribution, and bidirectional bus transceivers.
For engineers reviewing the 74LVTH240SJX datasheet, pinout, applications, or equivalent options, key selection criteria include bushold input capability, 3.3 V supply operation with 5 V tolerant I/O, high-speed propagation delay (≤4.6 ns), and SOIC-20 package compatibility for legacy board layouts.
Technical Context
The 74LVTH240SJX implements dual 4-bit inverting buffers with independent 3-STATE enable controls (OE1, OE2), supporting simultaneous or staggered bus control. Its bushold circuitry actively maintains input logic state without external biasing-critical for floating data lines in hot-pluggable or partially populated systems.
It uses advanced BiCMOS fabrication to achieve ABT-class speed (tPLH ≤ 4.6 ns at 3.3 V) while limiting ICCZ to 0.19 mA in disabled state. Input voltage range extends to 5.5 V, enabling direct interfacing with 5 V peripherals without level shifters.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Supply | 2.7 V to 3.6 V - ensures stable operation in 3.3 V rail systems with ±0.3 V tolerance |
| IOH/IOL Drive | –32 mA / +64 mA - supports driving heavy capacitive loads or multiple TTL inputs |
| tPLH/tPHL | ≤4.6 ns / ≤4.2 ns (CL = 50 pF) - enables high-speed bus timing in 50 MHz+ synchronous designs |
| VIH/VIL Thresholds | 2.0 V / 0.8 V - provides noise margin >0.4 V under worst-case 3.3 V operation |
| Bushold Current | ±75 µA at VI = 0.8 V/2.0 V - reliably holds unused inputs without external resistors |
| ESD Rating | HBM >2000 V - meets industrial handling requirements without special ESD precautions |
| Operating Temp | –40 °C to +85 °C - qualified for extended temperature industrial environments |
Pinout & Package
74LVTH240SJX is housed in a 20-lead Small Outline Package (SOP), EIAJ TYPE II, 5.3 mm wide (package code M20D), with standard SOIC footprint compatibility and gull-wing leads.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 19 | OE1, OE2 | Active-low 3-STATE enable inputs controlling first and second group of four outputs |
| 2–9 | I0–I7 | Inverting data inputs - each drives corresponding output with polarity inversion |
| 11–18 | O0–O7 | 3-STATE inverting outputs - high-impedance when OE1/OE2 = HIGH |
| 10, 20 | GND, VCC | Power terminals - decoupling capacitor placement near Pin 10 (GND) and Pin 20 (VCC) required |
Key Features
| Feature | Design Value |
|---|---|
| Bushold Inputs | Eliminates need for 10 kΩ pull-up resistors on unused data lines, reducing BOM count and PCB area |
| 5 V Tolerant I/O | Accepts 0–5.5 V input signals and drives 5 V TTL loads directly-no level-shifter IC required |
| Live Insertion Support | Enables hot-swap capability in backplane or modular systems without bus contention or glitches |
| Glitch-Free Power Sequencing | Outputs remain high-impedance during power-up/down transitions, preventing bus conflicts |
| Low ICCZ Current | 0.19 mA typical supply current in 3-STATE mode-reduces standby power in idle bus segments |
Applications
| Memory Address Buffering | Clock Distribution Network |
|---|---|
|
Use Scenario: Driving 16-bit address bus from low-power microcontroller to SRAM or Flash memory. IC Role / Device Role / Timing Role: Inverting octal buffer providing fanout and voltage-level translation between 3.3 V controller and 5 V memory. Use Value: Bushold inputs prevent floating address lines during reset; 64 mA sink capability ensures fast edge rates into 50 pF load per line. |
Use Scenario: Distributing system clock to multiple peripheral ICs with matched skew. IC Role / Device Role / Timing Role: Low-skew (≤1.0 ns) inverting buffer replicating clock signal with controlled impedance drive. Use Value: tOSHL/tOSLH ≤1.0 ns ensures synchronous sampling across all peripherals; 3.3 V supply minimizes jitter vs. 5 V alternatives. |
| Hot-Pluggable Backplane Interface | Legacy Bus Transceiver |
|
Use Scenario: Enabling safe insertion/extraction of daughter cards on shared data bus without disrupting host operation. IC Role / Device Role / Timing Role: 3-STATE line driver with live-insertion support and glitch-free power sequencing. Use Value: High-impedance outputs during power ramp-up prevent bus contention; ESD rating >2000 V HBM withstands connector mating stress. |
Use Scenario: Replacing obsolete 74LS240 in industrial control backplanes requiring 3.3 V logic upgrade. IC Role / Device Role / Timing Role: Functionally compatible drop-in replacement with identical pinout and truth table behavior. Use Value: Maintains existing PCB layout while improving speed (4× faster than LS), reducing power (ICCZ = 0.19 mA vs. ~10 mA), and adding bushold. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal buffer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LVC240APWR | No bushold; 3.3 V only I/O (not 5 V tolerant); lower drive (±24 mA) | Suitable for pure 3.3 V systems without legacy 5 V interface needs | Select when cost sensitivity outweighs 5 V compatibility and bushold requirement |
| 74ALVT240MTCX | Faster propagation (tPLH ≤ 3.2 ns); higher ICCZ (0.5 mA); no bushold | Better for ultra-high-speed timing-critical buses where power budget allows | Choose when sub-4 ns delay is mandatory and external pull-ups are acceptable |
Compared with SN74LVC240APWR and 74ALVT240MTCX, the 74LVTH240SJX uniquely combines 5 V tolerant I/O, bushold inputs, and industrial temperature range in a legacy-compatible SOP-20 package-making it optimal for mixed-voltage upgrades and field-serviceable systems.
Availability
74LVTH240SJX is available at Aetrix Electronics and suitable for memory subsystems, clock distribution networks, hot-pluggable backplanes, and legacy bus upgrades requiring stable component supply and long-term lifecycle support.
Supply support for 74LVTH240SJX 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
Fairchild Semiconductor was a U.S.-based semiconductor company specializing in analog and mixed-signal ICs, acquired by ON Semiconductor in 2016. Its legacy logic portfolio remains widely deployed in industrial and telecom infrastructure.
The 74LVTH240SJX belongs to Fairchild's LVT/H series of low-voltage BiCMOS buffers-designed specifically for 3.3 V systems needing backward compatibility with 5 V TTL buses and robust hot-swap operation.
FAQ
What is the function of bushold in the 74LVTH240SJX?
The bushold circuitry in the 74LVTH240SJX actively retains the last valid logic state on each input pin without external pull-up or pull-down resistors. This eliminates floating inputs during power-up, partial system initialization, or unconnected data lines-reducing design complexity and improving reliability in modular or hot-pluggable systems using the 74LVTH240SJX.
Does the 74LVTH240SJX support live insertion?
Yes, the 74LVTH240SJX supports live insertion and extraction due to its power-up/power-down high-impedance feature and bus-friendly output structure. During power transition, outputs remain in 3-STATE, preventing bus contention. This makes the 74LVTH240SJX suitable for backplane and modular chassis applications where cards are inserted or removed while the system is powered.
What is the maximum output drive capability of the 74LVTH240SJX?
The 74LVTH240SJX delivers –32 mA (source) and +64 mA (sink) per output under recommended operating conditions. This high drive strength allows it to directly interface with multiple TTL loads or drive moderate PCB trace capacitance without external buffering-key for maintaining signal integrity in dense bus architectures using the 74LVTH240SJX.
Is the 74LVTH240SJX pin-compatible with the standard 74LS240?
Yes, the 74LVTH240SJX is functionally and pin-compatible with the 74LS240, sharing identical pinout, truth table, and logic behavior. However, it operates at 3.3 V with 5 V tolerant I/O and adds bushold functionality-enabling direct replacement in legacy designs while upgrading performance, power efficiency, and robustness without PCB changes.
What package type does the 74LVTH240SJX use?
The 74LVTH240SJX uses a 20-lead Small Outline Package (SOP), EIAJ TYPE II, 5.3 mm wide (package code M20D). It is footprint-compatible with industry-standard SOIC-20 layouts, allowing drop-in replacement in existing designs and simplifying migration from through-hole or wider-body packages when using the 74LVTH240SJX.
74LVTH240SJX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- 74LVTH
- Package/Case:
- 20-SOIC (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:
- 32mA, 64mA
- Voltage - Supply:
- 2.7V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOP
74LVTH240SJX FAQ
1.How can I place an order for 74LVTH240SJX through Aetrix?
Please submit a Request for Quotation (RFQ) for 74LVTH240SJX 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 74LVTH240SJX reliable?
The price and inventory of 74LVTH240SJX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 74LVTH240SJX is usually 5 days.
3.What payment methods are accepted for 74LVTH240SJX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 74LVTH240SJX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 74LVTH240SJX?
74LVTH240SJX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 74LVTH240SJX 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 74LVTH240SJX?
For technical support, including 74LVTH240SJX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 74LVTH240SJX requirements.
6.How does Aetrix verify that 74LVTH240SJX is sourced from the original manufacturer or authorized distributors?
All 74LVTH240SJX 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 74LVTH240SJX meets industry standards.
7.What is the process for return or replacement of 74LVTH240SJX?
All 74LVTH240SJX units undergo pre-shipment inspection (PSI). If there is an issue with 74LVTH240SJX, 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 74LVTH240SJX part is unused and in its original packaging.
Return procedure for 74LVTH240SJX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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