My Inquiry
My Account
Texas Instruments SN74ALS620ADWG4
- Part No.:
- SN74ALS620ADWG4
- Manufacturer:
- Texas Instruments
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
SN74ALS620ADWG4.pdf
- Description:
- IC TXRX INVERT 5.5V 20SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,550
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74ALS620ADWG4 from Texas Instruments is an octal bus transceiver with 3-state inverting logic, designed for asynchronous bidirectional data transfer between A and B buses in legacy TTL systems. It features dual output-enable controls (OEAB/OEBA), local bus-latch capability, and operates over 0°C to 70°C with 5 V supply. Used in industrial backplane interfaces and memory expansion subsystems requiring level-shifted, isolated bus communication.
For engineers reviewing the SN74ALS620ADWG4 datasheet, SN74ALS620ADWG4 pinout, SN74ALS620ADWG4 application, or SN74ALS620ADWG4 equivalent, key selection criteria include its inverting 3-state output behavior, 24 mA low-level drive, 10 ns typical propagation delay (A↔B), and SOIC-20 package compatibility with legacy 74ALS system designs.
Technical Context
The SN74ALS620ADWG4 implements a dual-bus transceiver architecture with independent OEAB (A-to-B enable) and OEBA (B-to-A enable) inputs, enabling flexible direction control and simultaneous bus isolation or latching. Its inverting logic means A-bus inputs appear complemented on the B-bus outputs, and vice versa - critical for parity generation or signal inversion within bus arbitration schemes.
It uses bipolar ALS (Advanced Low-Power Schottky) technology, delivering TTL-compatible voltage thresholds (VIH = 2 V, VIL = 0.8 V), 0.4 V max VOL at 24 mA, and ICC of 33–47 mA depending on output state. The device supports true high-impedance isolation when both enables are inactive, and retains bus states when both enables are active and all external drivers are tri-stated.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Function | Inverting octal bus transceiver with dual 3-state control |
| Supply Voltage | 4.5 V to 5.5 V - compatible with standard 5 V TTL rails; absolute max 7 V |
| Propagation Delay | 2–10 ns (A↔B), 2–18 ns (enable→output) - ensures tight timing in high-speed backplane transfers |
| Output Drive | IOL = 24 mA (min), VOL ≤ 0.4 V - sufficient to drive 10+ TTL loads or terminate stubbed buses |
| Operating Temperature | 0°C to 70°C - qualified for commercial-grade industrial control and instrumentation |
| Input Thresholds | VIH = 2.0 V, VIL = 0.8 V - matches standard TTL logic levels for seamless integration |
| Package | SOIC-20 (DW), 7.5 mm × 12.8 mm body, 1.27 mm pitch - surface-mount compatible with automated assembly |
Pinout & Package
SN74ALS620ADWG4 is housed in a 20-pin SOIC (DW) package with standard 1.27 mm lead pitch and 2.65 mm maximum height. Pin 1 is marked by a beveled corner or notch; leads are gull-wing shaped and RoHS-compliant (NiPdAu finish).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OEAB) | A-to-B Output Enable | Active-low control: enables A-bus data transmission to B-bus when low |
| 2–9 (A1–A8) | A-Bus Inputs/Outputs | Bidirectional I/O pins; driven by A-side logic, present inverted values on B-bus when OEAB active |
| 10 (GND) | Ground Reference | Primary power return path; must be low-impedance for noise immunity in bus systems |
| 11 (VCC) | Power Supply | +5 V supply input; requires local 0.1 µF ceramic decoupling near pin |
| 12–19 (B1–B8) | B-Bus Inputs/Outputs | Bidirectional I/O pins; present inverted A-bus data when OEAB active, or inverted B-bus data on A-bus when OEBA active |
| 20 (OEBA) | B-to-A Output Enable | Active-low control: enables B-bus data transmission to A-bus when low |
Key Features
| Feature | Design Value |
|---|---|
| Local Bus-Latch Capability | Simultaneous assertion of OEAB and OEBA holds both A and B bus states without external latches |
| Inverting Logic Path | Guarantees complementary data transfer - essential for differential signaling, parity, or logic inversion stages |
| Dual Independent Enables | Enables asymmetric bus control: e.g., A→B only while B remains isolated, preventing contention |
| TTL-Compatible Interface | Meets standard 74ALS input/output voltage and current specs - drop-in replacement in legacy 74-series designs |
| High Noise Immunity | VIK = –1.2 V (input clamp), IIL = –0.1 mA - suppresses ground bounce and ESD-induced glitches |
Applications
| Industrial Backplane Interface | Memory Expansion Subsystem |
|---|---|
Use Scenario: Bidirectional data routing between CPU and peripheral modules across a shared 8-bit backplane with address/data multiplexing. IC Role / Device Role / Timing Role: SN74ALS620ADWG4 acts as a direction-controlled bus isolator, synchronizing data flow using OEAB/OEBA signals derived from bus arbitration logic. Use Value: Prevents bus contention during read/write transitions and maintains signal integrity across 15 cm traces with 24 mA drive strength. |
Use Scenario: Expanding RAM capacity in embedded controllers by connecting additional SRAM banks to a constrained data bus. IC Role / Device Role / Timing Role: SN74ALS620ADWG4 buffers and inverts address/data lines between main MCU bus and auxiliary memory bank, controlled by chip-select timing. Use Value: Enables clean 10 ns propagation delay and 0.4 V VOL at full load - critical for meeting SRAM tACC and tAA timing windows. |
| Legacy Test Equipment Bus | Programmable Logic Interconnect |
Use Scenario: Signal conditioning and isolation between FPGA-based test pattern generators and DUT interface boards using 5 V TTL signaling. IC Role / Device Role / Timing Role: SN74ALS620ADWG4 serves as a programmable polarity translator and bus driver, configured via FPGA GPIO to invert or pass-through test vectors. Use Value: Inverting capability eliminates need for external inverters; 24 mA drive ensures reliable edge rates into 50 Ω scope probes or cable loads. |
Use Scenario: Interfacing multiple GAL/PAL devices on a shared development board where logic polarity must be dynamically adjusted. IC Role / Device Role / Timing Role: SN74ALS620ADWG4 provides configurable bus coupling between PLD I/O banks, with OEAB/OEBA synchronized to PLD clock enables. Use Value: Local latch mode allows temporary storage of PLD configuration bits without external flip-flops, reducing component count. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal bus transceiver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74ALS623ADW | True (non-inverting) logic; otherwise identical pinout, timing, and drive specs | Used where signal polarity preservation is required (e.g., direct data mirroring) | Select when inverting behavior of SN74ALS620ADWG4 conflicts with system-level logic flow |
| SN74AS623DW | Faster propagation (1–9 ns vs. 2–10 ns); higher IOL (64 mA); AS-series propagation characteristics | Suitable for higher-speed backplanes (>25 MHz) where ALS timing margins are insufficient | Choose for performance-critical upgrades where layout changes accommodate AS-series higher ICC (up to 189 mA) |
Compared with SN74ALS620ADWG4, SN74ALS623ADW preserves signal polarity but shares identical packaging and thermal profile, while SN74AS623DW delivers 2× speed and 2.7× drive at the cost of 4× higher supply current - making it suitable for performance-tier replacements rather than drop-in swaps.
Availability
SN74ALS620ADWG4 is available at Aetrix Electronics and suitable for industrial backplane interfaces, memory expansion subsystems, and legacy test equipment requiring stable component supply and long-term obsolescence management.
Supply support for SN74ALS620ADWG4 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
Texas Instruments is a global semiconductor leader with decades of expertise in logic ICs, analog, and embedded processing solutions, serving automotive, industrial, and communications markets.
The SN74ALS620ADWG4 belongs to TI's legacy 74ALS logic family, engineered for high-speed, low-power TTL-compatible operation in industrial control, instrumentation, and computer peripheral systems.
FAQ
What is the logic polarity of SN74ALS620ADWG4?
The SN74ALS620ADWG4 implements inverting logic: data presented on the A-bus appears complemented on the B-bus outputs when OEAB is active, and vice versa when OEBA is active. This is confirmed in the function table and logic diagrams of the SDAS226A datasheet, distinguishing it from the true-logic SN74ALS623A and SN74AS623 variants.
Does SN74ALS620ADWG4 support bus latching?
Yes - SN74ALS620ADWG4 supports local bus-latch functionality. When both OEAB and OEBA are asserted low simultaneously, the device enters a transparent latched state: each output reinforces its corresponding input, allowing both A and B buses to retain their last valid states without external storage elements.
What is the maximum output sink current for SN74ALS620ADWG4?
The SN74ALS620ADWG4 guarantees a minimum low-level output current (IOL) of 24 mA per pin at VOL ≤ 0.4 V, with VCC = 4.5 V. This rating applies across the full 0°C to 70°C operating range and is validated per the electrical characteristics table in the SDAS226A datasheet.
Is SN74ALS620ADWG4 pin-compatible with SN74ALS623ADW?
Yes - SN74ALS620ADWG4 and SN74ALS623ADW share identical SOIC-20 (DW) pinouts, package dimensions, and terminal assignments. The only functional difference is logic polarity (inverting vs. true), making them mechanically interchangeable in existing layouts where polarity can be accommodated in firmware or upstream logic.
What is the recommended operating voltage range for SN74ALS620ADWG4?
The SN74ALS620ADWG4 is specified for reliable operation with a supply voltage (VCC) between 4.5 V and 5.5 V. Operation outside this range - including the absolute maximum rating of 7 V - risks parametric failure or accelerated degradation and is not supported under recommended conditions.
SN74ALS620ADWG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74ALS
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Bulk
- Product Status:
- Discontinued at Digi-Key
- Logic Type:
- Transceiver, Inverting
- Number of Elements:
- 1
- Number of Bits per Element:
- 8
- Input Type:
- -
- Output Type:
- 3-State
- Current - Output High, Low:
- 15mA, 24mA
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOIC
SN74ALS620ADWG4 FAQ
1.How can I place an order for SN74ALS620ADWG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74ALS620ADWG4 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 SN74ALS620ADWG4 reliable?
The price and inventory of SN74ALS620ADWG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74ALS620ADWG4 is usually 5 days.
3.What payment methods are accepted for SN74ALS620ADWG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74ALS620ADWG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74ALS620ADWG4?
SN74ALS620ADWG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74ALS620ADWG4 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 SN74ALS620ADWG4?
For technical support, including SN74ALS620ADWG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74ALS620ADWG4 requirements.
6.How does Aetrix verify that SN74ALS620ADWG4 is sourced from the original manufacturer or authorized distributors?
All SN74ALS620ADWG4 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 SN74ALS620ADWG4 meets industry standards.
7.What is the process for return or replacement of SN74ALS620ADWG4?
All SN74ALS620ADWG4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74ALS620ADWG4, 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 SN74ALS620ADWG4 part is unused and in its original packaging.
Return procedure for SN74ALS620ADWG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74ALS620ADWG4 Tags
-
SN74LVC1G17DBVR
Texas Instruments
-
SN74LVC1G07DCKR
Texas Instruments
-
SN74LVC1G17DCKR
Texas Instruments
-
SN74LVC1G07DBVR
Texas Instruments
-
SN74LVC1G125DCKR
Texas Instruments
-
SN74AHCT1G126DBVR
Texas Instruments
-
SN74LVC1G125DBVR
Texas Instruments
-
SN74AHCT1G125DBVR
Texas Instruments
-
SN74LVC2G17DBVR
Texas Instruments
-
SN74LVC2G07DCKR
Texas Instruments
-
SN74LVC1G34DCKR
Texas Instruments
-
SN74LVC2G17DCKR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
