SN74BCT640NIn StockTexas Instruments
SN74BCT640N is an octal bus transceiver with 3-state outputs and bidirectional direction control, featuring IOL=64mA and 50pF load capacitance in DIP-20 package. From $3.77 with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Dual-In-Line Packages
- Pin Count
- 20
- Lifecycle
- ACTIVE
- Datasheet
- SN74BCT640N Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $3.7700(MOQ 1)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Octal bidirectional bus transceiver with 3-state outputs for high-drive applications
- High output drive current: IOL=64mA at VOL=0.5V, enabling direct TTL/CMOS bus interfacing
- Common direction control for all 8 bits, simplifying system-level bus management
- Compatible with BCT/FBT logic family for mixed-voltage system designs
- DIP-20 package for easy prototyping and through-hole assembly
Applications
The SN74BCT640N is widely used in microprocessor bus interfacing, memory expansion, and data buffering applications where bidirectional data transfer between two buses is required. Its high sink current capability makes it suitable for driving heavily loaded backplane buses in industrial control systems and communication equipment. The device is also commonly employed in test equipment, FPGA interface boards, and legacy system upgrades where reliable TTL-level signal translation is needed.
Specifications
| YTEOL | 15 |
| Additional Feature | DIRECTION CONTROL; IOL = 24MA @ VOL = 0.5V & IOH = 3MA @ VOH = 2.4V FOR PORT A |
| Control Type | COMMON CONTROL |
| Count Direction | BIDIRECTIONAL |
| Family | BCT/FBT |
| JESD-30 Code | R-PDIP-T20 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 50pF |
| Logic IC Type | BUS TRANSCEIVER |
| Max I(ol) | 0.064A |
| Number of Bits | 8 |
| Number of Functions | 8 |
| Number of Ports | 2 |
| Output Characteristics | 3-STATE |
| Output Polarity | INVERTED |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | DIP20,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Packing Method | TUBE |
| Power Supply Current-Max (ICC) | 94mA |
| Prop. Delay@Nom-Sup | 6.5ns |
| Propagation Delay (tpd) | 3.7ns |
| Qualification Status | Not Qualified |
| Schmitt Trigger | NO |
| Supply Voltage-Max (Vsup) | 5.5V |
| Supply Voltage-Min (Vsup) | 4.5V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | NO |
| Technology | BICMOS |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
| Country of Origin | Malaysia |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74BCT640N:
Bus Transceiver, BCT/FBT Series, 8-Func, 8-Bit, Inverted Output, BICMOS, PDSO20
Bus Transceiver, BCT/FBT Series, 1-Func, 8-Bit, Inverted Output, BICMOS, PDSO20
Frequently Asked Questions
What is the maximum output sink current of the SN74BCT640N?
The SN74BCT640N supports a maximum output sink current (IOL) of 64mA at VOL=0.5V for Port A, making it suitable for driving heavily loaded TTL and CMOS buses in high-fanout applications.
How does the direction control work on the SN74BCT640N?
The SN74BCT640N uses a common direction control (DIR) pin that simultaneously sets the data flow direction for all 8 bit lines. When DIR is HIGH, data flows from B to A; when LOW, data flows from A to B, enabling easy bidirectional bus management.
What package type does the SN74BCT640N come in and what are its key dimensions?
The SN74BCT640N is available in a 20-pin Dual-In-Line (PDIP) package (JESD-30 code R-PDIP-T20), which is well-suited for through-hole PCB assembly and breadboard prototyping with standard 2.54mm pin pitch.
Can the SN74BCT640N replace other octal bus transceivers like the 74LS640 or 74HCT640?
Yes, the SN74BCT640N is pin-compatible with standard 74640 series octal bus transceivers. The BCT variant offers improved drive strength and faster switching compared to 74LS640, and is generally interchangeable with 74HCT640 in 5V systems, though timing and drive characteristics should be verified for critical designs.
What is the recommended load capacitance for the SN74BCT640N?
Texas Instruments specifies a load capacitance (CL) of 50pF for the SN74BCT640N, which represents the maximum capacitive load per output for meeting the device's switching time and drive specifications under standard test conditions.
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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.
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