SN74AS645NIn StockTexas Instruments
SN74AS645N is an octal bus transceiver with 3-state outputs, featuring bidirectional data flow with common direction control, 50pF load capacitance, and 64mA output current. From $3.57, in stock worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Dual-In-Line Packages
- Pin Count
- 20
- Lifecycle
- ACTIVE
- Datasheet
- SN74AS645N Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $3.5663(MOQ 1)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Octal (8-bit) bidirectional bus transceiver with 3-state outputs for high-impedance bus isolation
- Advanced Schottky (AS) logic family for high-speed operation with low propagation delay
- Common direction control pin simplifies system-level bus management
- 64mA output sink current supports heavy bus loads in industrial environments
- DIP-20 package for easy through-hole assembly and prototyping
Applications
The SN74AS645N is widely used in microprocessor and microcontroller bus interfaces where bidirectional data transfer between two buses is required. It is suitable for memory expansion systems, backplane data buses, and industrial control equipment demanding fast and reliable signal switching. Its 3-state output capability makes it ideal for multiplexed bus architectures in embedded and computing systems.
Specifications
| YTEOL | 15 |
| Additional Feature | WITH DIRECTION CONTROL |
| Control Type | COMMON CONTROL |
| Count Direction | BIDIRECTIONAL |
| Family | AS |
| 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 | TRUE |
| 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) | 149mA |
| Prop. Delay@Nom-Sup | 10ns |
| Propagation Delay (tpd) | 9ns |
| 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 | TTL |
| 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
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What logic family does the SN74AS645N belong to, and what are its speed characteristics?
The SN74AS645N belongs to the Advanced Schottky (AS) logic family, which offers higher switching speeds compared to standard TTL or LS logic. It features low propagation delay times, making it suitable for high-speed bus applications where fast data transfer between buses is critical.
How does the direction control work on the SN74AS645N?
The SN74AS645N uses a single common direction control (DIR) pin to determine the flow of data between Port A and Port B. When DIR is high, data flows from B to A; when DIR is low, data flows from A to B. An Output Enable (OE) pin controls the 3-state outputs for bus isolation.
What are typical applications for the SN74AS645N octal bus transceiver?
Typical applications include microprocessor data bus buffering, memory interface circuits, backplane bus drivers, and industrial control systems. Its bidirectional capability and 3-state outputs make it ideal for any design requiring isolated, switchable 8-bit data paths between two subsystems.
Can the SN74AS645N be used as a replacement for the 74LS645 or 74F645?
Yes, the SN74AS645N is functionally compatible with 74LS645 and 74F645 octal bus transceivers and can generally be used as a drop-in replacement in DIP-20 footprint designs. However, verify timing parameters and power supply requirements, as the AS family has different propagation delay and drive characteristics.
What is the package type and pin count of the SN74AS645N?
The SN74AS645N comes in a 20-pin Dual In-line Package (DIP-20), which is ideal for through-hole PCB assembly. The wide 0.6-inch body provides easy handling and compatibility with standard IC sockets used in development and production environments.
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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.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $7.1325 | $7.13 |
| 15+ | $4.7552 | $71.33 |
| 54+ | $4.3986 | $237.52 |
| 228+ | $3.9229 | $894.42 |
| 511+ | $3.5663 | $1822.38 |
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