My Inquiry
My Account
Texas Instruments SN74ALS244CDW
- Part No.:
- SN74ALS244CDW
- Manufacturer:
- Texas Instruments
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
SN74ALS244CDW.pdf
- Description:
- IC BUF NON-INVERT 5.5V 20SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:493
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74ALS244CDW from Texas Instruments is an octal non-inverting buffer/line driver with 3-state outputs, designed for memory address and bus driving in TTL-compatible systems. It operates from 4.5 V to 5.5 V, delivers ±12 mA output drive, supports 0°C to 70°C ambient, and features pnp input structure to reduce DC loading on upstream logic - commonly used in industrial control backplanes and legacy data acquisition interfaces.
For engineers reviewing the SN74ALS244CDW datasheet, SN74ALS244CDW pinout, SN74ALS244CDW application, or SN74ALS244CDW equivalent, key selection criteria include its 20-pin SOIC (DW) package, dual independent 3-state enable inputs (1OE, 2OE), symmetrical propagation delays (tPLH/tPHL ≤ 10 ns), and compatibility with ALS-family timing and drive requirements in bus-hold-free digital subsystems.
Technical Context
The SN74ALS244CDW implements two independent 4-bit non-inverting buffer groups (1A1–1A4 → 1Y1–1Y4; 2A1–2A4 → 2Y1–2Y4), each controlled by a dedicated active-low 3-state enable (1OE, 2OE). Its pnp-input architecture lowers input current draw versus standard TTL, improving fanout in dense address buffers.
Output switching adheres to ALS family specifications: VOL ≤ 0.4 V at IOL = 12 mA, VOH ≥ 2.4 V at IOH = –12 mA, and 3-state leakage |IOZ| ≤ 20 µA. Propagation delay is specified under CL = 50 pF, R1 = R2 = 500 Ω, with tPZH/tPZL ≤ 20 ns enabling reliable use in 25 MHz bus environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 4.5 V to 5.5 V - ensures compatibility with 5 V TTL and ALS logic rails without level-shifting. |
| Operating Temperature | 0°C to 70°C - qualified for commercial-grade embedded and industrial control applications. |
| Output Drive (IOL) | 12 mA - sufficient to drive 10 standard TTL loads or terminate short stubs on parallel buses. |
| Propagation Delay | ≤10 ns (tPLH/tPHL) - enables reliable operation up to ~25 MHz clocked bus cycles. |
| 3-State Enable Time | tPZH ≤ 20 ns - guarantees fast bus release for time-critical arbitration or multiplexing. |
| Input Structure | pnp-based - reduces input current (IIL ≤ –0.1 mA), minimizing loading on preceding gate outputs. |
| Package | SOIC-20 (DW) - surface-mount footprint compatible with automated assembly and IPC-7351 land patterns. |
Pinout & Package
SN74ALS244CDW uses a 20-pin SOIC (DW) package, 7.5 mm × 12.8 mm body, 1.27 mm lead pitch, and 2.65 mm max height per JEDEC MS-013. Pin 1 is located at the top-left corner with a beveled edge marker.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 19 | 1OE, 2OE | Active-low 3-state enable inputs - independently disable Group 1 (pins 3,5,7,9) or Group 2 (pins 12,14,16,18) outputs. |
| 2, 4, 6, 8 | 1A1–1A4 | Group 1 non-inverting input signals - routed directly to corresponding Y outputs when 1OE is low. |
| 3, 5, 7, 9 | 1Y1–1Y4 | Group 1 buffered outputs - high-impedance when 1OE is high; otherwise replicate 1A1–1A4. |
| 10 | GND | Ground reference - must be connected to system common return for stable logic thresholds and noise immunity. |
| 11 | VCC | Positive supply - decoupling capacitor (0.1 µF ceramic) required within 10 mm of this pin. |
| 12, 14, 16, 18 | 2Y1–2Y4 | Group 2 buffered outputs - enabled only when 2OE (pin 19) is low. |
| 13, 15, 17, 20 | 2A1–2A4 | Group 2 non-inverting inputs - electrically isolated from Group 1; share no internal resources. |
Key Features
| Feature | Design Value |
|---|---|
| 3-State Output Control | Dual independent OE pins allow selective bus isolation of two 4-bit channels without external gating logic. |
| pnp Input Structure | Reduces input current to ≤ –0.1 mA, increasing fanout capability and lowering power dissipation in cascaded buffers. |
| TTL-Compatible Interface | VIH = 2.0 V, VIL = 0.8 V - interoperable with standard 74LS, 74ALS, and 74AS families without level translation. |
| Low-Noise Switching | Controlled edge rates and symmetrical tPLH/tPHL minimize ground bounce and crosstalk in high-density PCB layouts. |
| Industrial SOIC Packaging | DW package supports reflow soldering per J-STD-020 Level-1, with NIPDAU lead finish and RoHS compliance. |
Applications
| Memory Address Buffering | Parallel Bus Isolation |
|---|---|
Use Scenario: Driving 16-bit address lines from a microcontroller to multiple SRAM or EPROM chips on a shared bus. IC Role / Device Role / Timing Role: Non-inverting buffer with 3-state outputs isolates address latches during memory access arbitration. Use Value: Enables clean address transitions with <10 ns propagation delay and prevents bus contention via independent OE control. | Use Scenario: Interfacing a CPU data bus to peripheral modules (e.g., ADC, DAC, UART) requiring selective enable/disable. IC Role / Device Role / Timing Role: Bidirectional bus driver that isolates peripherals when not selected, reducing capacitive loading. Use Value: Dual OE inputs allow simultaneous or staggered peripheral activation without additional logic gates. |
| Legacy Industrial Backplane | Test Equipment Signal Conditioning |
Use Scenario: Extending TTL-level control signals across a 200 mm backplane in programmable logic controllers (PLCs). IC Role / Device Role / Timing Role: Line driver compensating for trace capacitance and noise pickup on long parallel runs. Use Value: 12 mA drive strength maintains signal integrity over 15 cm traces at 5 V, with pnp inputs minimizing source loading. | Use Scenario: Conditioning digital trigger and strobe signals in automated test equipment (ATE) before routing to DUT interface boards. IC Role / Device Role / Timing Role: Glitch-free signal repeater with fast enable/disable for precise timing window control. Use Value: tPZH ≤ 20 ns and tPLZ ≤ 13 ns support sub-50 ns pulse gating for high-speed stimulus sequencing. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal buffer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74ALS244CDWR | Same die and specs; tape-and-reel packaging (2000 pcs/reel) vs. tube (obsolete SN74ALS244CDW). | No functional difference - identical electrical behavior and pinout; preferred for automated SMT assembly. | Select SN74ALS244CDWR for new designs requiring volume production and RoHS-compliant NIPDAU finish. |
| SN74AS244ADWR | Faster propagation (tPLH ≤ 6.2 ns), higher drive (IOL = 48 mA), but increased ICC (up to 90 mA) and tighter VIH/VIL margins. | Better suited for high-speed bus applications >33 MHz; less tolerant of marginal input levels or noisy environments. | Choose SN74AS244ADWR only when speed outweighs power and noise robustness requirements. |
Compared with SN74ALS244CDW, SN74ALS244CDWR offers identical performance in modern packaging, while SN74AS244ADWR trades ALS-level noise immunity and power efficiency for raw speed - making the original ideal for cost-sensitive, noise-prone industrial backplanes where timing margin exceeds 10 ns.
Availability
SN74ALS244CDW is available at Aetrix Electronics and suitable for memory address buffering, parallel bus isolation, legacy industrial backplane expansion, and test equipment signal conditioning requiring stable component supply and long-term obsolescence management.
Supply support for SN74ALS244CDW 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 specializing in analog, embedded processing, and logic solutions with over 50 years of innovation in industrial, automotive, and communications markets.
The SN74ALS244CDW belongs to TI's legacy ALS (Advanced Low-Power Schottky) logic family, engineered for high-speed, low-power bus interfacing in commercial-grade systems where reliability and TTL compatibility are critical.
FAQ
What is the maximum operating temperature range for SN74ALS244CDW?
The SN74ALS244CDW is characterized for operation from 0°C to 70°C, meeting commercial-grade environmental requirements. It is not rated for extended temperature ranges like the military-spec SN54ALS244C (–55°C to 125°C); using SN74ALS244CDW outside 0–70°C may result in undefined timing or output behavior.
Does SN74ALS244CDW support true bidirectional data flow?
No, SN74ALS244CDW is a unidirectional octal buffer - it has separate input (A) and output (Y) terminals with no internal direction control. For bidirectional applications, a transceiver such as SN74ALS245CDW would be required. The 3-state outputs allow bus sharing but do not reverse signal path direction.
Can SN74ALS244CDW drive standard TTL loads directly?
Yes, SN74ALS244CDW can drive up to 10 standard TTL loads (each drawing 1.6 mA) per output, based on its guaranteed IOL = 12 mA and VOH ≥ 2.4 V at IOH = –12 mA. Its pnp input structure also minimizes loading on upstream TTL sources, preserving noise margins in cascaded configurations.
Is SN74ALS244CDW pin-compatible with SN74ALS244CN?
Yes, SN74ALS244CDW and SN74ALS244CN share identical pin functions and logic behavior; they differ only in package type (SOIC-20 vs. PDIP-20) and mechanical dimensions. Both use the same 20-pin dual-in-line pinout mapping, allowing direct PCB layout substitution when mechanical constraints permit.
What is the recommended decoupling for SN74ALS244CDW?
A 0.1 µF ceramic capacitor placed between VCC (pin 11) and GND (pin 10), with leads ≤ 5 mm long and mounted within 10 mm of the SN74ALS244CDW, is recommended. This suppresses high-frequency supply noise induced by simultaneous output switching and ensures stable VOH/VOL across all eight drivers.
SN74ALS244CDW Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74ALS
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Logic Type:
- Buffer, Non-Inverting
- Number of Elements:
- 2
- Number of Bits per Element:
- 4
- 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
SN74ALS244CDW FAQ
1.How can I place an order for SN74ALS244CDW through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74ALS244CDW 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 SN74ALS244CDW reliable?
The price and inventory of SN74ALS244CDW are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74ALS244CDW is usually 5 days.
3.What payment methods are accepted for SN74ALS244CDW?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74ALS244CDW transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74ALS244CDW?
SN74ALS244CDW orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74ALS244CDW 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 SN74ALS244CDW?
For technical support, including SN74ALS244CDW datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74ALS244CDW requirements.
6.How does Aetrix verify that SN74ALS244CDW is sourced from the original manufacturer or authorized distributors?
All SN74ALS244CDW 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 SN74ALS244CDW meets industry standards.
7.What is the process for return or replacement of SN74ALS244CDW?
All SN74ALS244CDW units undergo pre-shipment inspection (PSI). If there is an issue with SN74ALS244CDW, 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 SN74ALS244CDW part is unused and in its original packaging.
Return procedure for SN74ALS244CDW:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74ALS244CDW 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…
