SN74LS640-1DWG4 Texas Instruments Integrated Circuit (Small Outline Packages) In Stock
Texas Instruments SN74LS640-1DWG4 is an 8-bit inverting bidirectional bus transceiver with direction control in a 20-pin SOIC package at 5V. Available from stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 20
- Lifecycle
- OBSOLETE
- Datasheet
- SN74LS640-1DWG4 Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 8-bit inverting bidirectional bus transceiver with direction control for flexible data flow management on shared bus architectures
- Common control type with bidirectional count direction enables simple interface between two independent data buses with a single control signal
- 5V LS-family logic with 24 mA maximum low-level output current for robust bus drive capability
- 20-pin SOIC (R-PDSO-G20) package with lead-free RoHS-compliant (JESD-609 e4) construction for modern assembly
Applications
The SN74LS640-1DWG4 is used in microprocessor and microcontroller bus systems where bidirectional data transfer between two buses must be controlled and electrically isolated. Its inverting output characteristic is useful in designs where signal polarity inversion is required as part of the bus interface logic. The 8-bit width makes it ideal for interfacing 8-bit data buses in legacy industrial computers, memory expansion boards, and backplane communication systems.
Specifications
| YTEOL | 0 |
| Additional Feature | WITH DIRECTION CONTROL |
| Control Type | COMMON CONTROL |
| Count Direction | BIDIRECTIONAL |
| Family | LS |
| JESD-30 Code | R-PDSO-G20 |
| JESD-609 Code | e4 |
| Logic IC Type | BUS TRANSCEIVER |
| Max I(ol) | 0.024A |
| Number of Bits | 8 |
| Number of Functions | 1 |
| Number of Ports | 2 |
| Output Characteristics | 3-STATE |
| Output Polarity | INVERTED |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP20,.4 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Packing Method | TUBE |
| Peak Reflow Temperature (Cel) | 260 |
| Power Supply Current-Max (ICC) | 95mA |
| Prop. Delay@Nom-Sup | 15ns |
| Propagation Delay (tpd) | 15ns |
| Qualification Status | Not Qualified |
| Supply Voltage-Max (Vsup) | 5.25V |
| Supply Voltage-Min (Vsup) | 4.75V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | YES |
| Technology | TTL |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | NICKEL PALLADIUM GOLD |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| HTS Code | 8542.39.00.60 |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74LS640-1DWG4:
Bus Transceiver, LS Series, 1-Func, 8-Bit, Inverted Output, TTL, PDSO20
Frequently Asked Questions
What is the function of the SN74LS640-1DWG4?
The SN74LS640-1DWG4 is an 8-bit inverting bidirectional bus transceiver. It allows data to flow in both directions between two buses under the control of a direction control signal, with inverted logic output, making it suitable for interfacing between microprocessor data buses and peripheral devices.
What logic family and supply voltage does the SN74LS640-1DWG4 use?
The SN74LS640-1DWG4 belongs to the LS (Low-Power Schottky) logic family and operates at 5V. The LS family offers a good balance between speed and power consumption for classic TTL-compatible bus interface applications in both legacy and new embedded system designs.
What package does the SN74LS640-1DWG4 use?
The SN74LS640-1DWG4 is housed in a 20-pin Small Outline IC (SOIC) package, identified by JESD-30 code R-PDSO-G20. This standard surface-mount package is compatible with automated pick-and-place assembly and is widely used in industrial and computing applications.
Is the SN74LS640-1DWG4 RoHS compliant?
Yes, the SN74LS640-1DWG4 carries a JESD-609 code of e4, confirming it is lead-free and RoHS compliant. This makes it suitable for products sold in regulated markets such as the European Union, where restriction of hazardous substances directives apply to electronic components.
What is the maximum output sink current of the SN74LS640-1DWG4?
The SN74LS640-1DWG4 provides a maximum low-level output current (I_OL) of 24 mA, giving it sufficient drive strength to sink current from bus lines with multiple loads. This is important in bus transceiver applications where the output must reliably pull lines low despite capacitive loading.
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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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