SN74ALS640BDWIn StockTexas Instruments
SN74ALS640BDW is an octal bus transceiver with 3-state outputs in ALS TTL logic by Texas Instruments. Key specs: 8-bit bidirectional data flow, 3-state outputs, 4.5V–5.5V supply voltage, 20-pin SOIC package. From $1.50, in stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- —
- Lifecycle
- ACTIVE
- Datasheet
- N/A
- Price
- From $1.5000(MOQ 1)
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Octal (8-bit) bidirectional bus transceiver for high-density data transfer
- 3-state outputs enable multiple devices to share a common bus without conflict
- Advanced Low-power Schottky (ALS) technology for reduced power consumption vs standard TTL
- Wide operating voltage range: 4.5V to 5.5V supply
- 20-pin SOIC (DW) package for surface-mount PCB designs
- Direction control pin (DIR) for flexible data flow management
- Output enable (OE) pin for easy bus isolation and tri-state control
Applications
The SN74ALS640BDW is widely used in microprocessor and microcontroller systems where bidirectional data bus buffering is required between different logic sections. It is ideal for memory interface circuits, industrial control boards, and communication equipment where 3-state bus sharing among multiple devices is essential. The device also finds application in data acquisition systems, test equipment, and backplane bus drivers requiring reliable ALS-level TTL compatibility.
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What is the SN74ALS640BDW and what does it do?
The SN74ALS640BDW is an octal bus transceiver with 3-state outputs from Texas Instruments. It provides bidirectional 8-bit data transfer between two buses, using a direction control pin (DIR) to select data flow and an active-low output enable (OE) to tri-state all outputs. It operates from a 4.5V to 5.5V supply and is housed in a 20-pin SOIC package.
What package does the SN74ALS640BDW come in?
The SN74ALS640BDW is available in a 20-pin wide SOIC package (DW suffix), which is a standard surface-mount package with 1.27mm pin pitch. This makes it suitable for high-density PCB layouts in industrial and commercial electronics applications.
What is the difference between SN74ALS640 and SN74ALS641?
The SN74ALS640 features inverting (complementary) outputs, meaning data output on the B bus is the logical inversion of data on the A bus. The SN74ALS641 features non-inverting outputs, passing data without inversion. Both are octal bus transceivers with 3-state outputs operating in the ALS TTL logic family at 4.5V–5.5V.
What are typical applications for the SN74ALS640BDW?
The SN74ALS640BDW is commonly used in microprocessor bus buffering, memory interface circuits, industrial control systems, and communication equipment. Its 3-state outputs make it ideal for multi-device bus sharing architectures, while ALS technology ensures low power consumption compared to standard TTL devices.
Where can I buy the SN74ALS640BDW and what is the price?
The SN74ALS640BDW is available at FindMyChip starting from $1.50. We offer worldwide shipping and can source stock from multiple distributors. Submit a quote request on this page to receive competitive pricing and lead time information for your required quantity.
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Why Buy from FindMyChip
About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $2.3100 | $2.31 |
| 100+ | $1.7300 | $173.00 |
| 1000+ | $1.5000 | $1500.00 |
In Stock · 24h Response · Worldwide Shipping
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