SN74ALS244CDB Texas Instruments Integrated Circuit (Small Outline Packages) In Stock
SN74ALS244CDB is an 8-channel unidirectional ALS-family bus buffer with 3-state outputs in a 20-pin SOIC package from Texas Instruments. It operates on a 4.5 V to 5.5 V supply with active-low output-enable control and supports 50 pF load capacitance per channel. Available from stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 20
- Lifecycle
- OBSOLETE
- Datasheet
- SN74ALS244CDB 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-channel unidirectional buffer with 3-state outputs and active-low output-enable for bus isolation
- ALS bipolar technology operating from 4.5 V to 5.5 V with 24 mA sink current per output
- 50 pF load capacitance rating and 20-pin SOIC package for high-density bus driver applications
- Two independent 4-bit banks each with its own enable for flexible partial-bus control
Applications
SN74ALS244CDB is used in address bus buffering, memory expansion circuits, and data isolation stages in industrial controllers and embedded systems where 5 V TTL-compatible bus driving is required. Its two independent 4-bit enable groups allow selective buffering of address versus data lines from a single device, reducing chip count in bus-structured designs. The SOIC-20 package suits SMT layouts in VMEbus, ISA, and custom backplane cards needing robust ALS-speed outputs.
Specifications
| Pbfree Code | Yes |
| YTEOL | 0 |
| Control Type | ENABLE LOW |
| Count Direction | UNIDIRECTIONAL |
| Family | ALS |
| JESD-30 Code | R-PDSO-G20 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 50pF |
| Logic IC Type | BUS DRIVER |
| Max I(ol) | 0.024A |
| Number of Bits | 4 |
| Number of Functions | 8 |
| Number of Ports | 2 |
| Output Characteristics | 3-STATE |
| Output Polarity | TRUE |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SSOP20,.3 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE, SHRINK PITCH |
| Packing Method | TR, 13 INCH |
| Power Supply Current-Max (ICC) | 24mA |
| Prop. Delay@Nom-Sup | 10ns |
| Propagation Delay (tpd) | 10ns |
| Supply Voltage-Max (Vsup) | 5.5V |
| Supply Voltage-Min (Vsup) | 4.5V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | YES |
| Technology | TTL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | GULL WING |
| Terminal Pitch | 0.65mm |
| Terminal Position | DUAL |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
| Country of Origin | Malaysia |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74ALS244CDB:
Frequently Asked Questions
How does SN74ALS244CDB differ from the LS244 in drive strength and speed for a 5 V bus design?
SN74ALS244CDB uses Advanced Low-power Schottky (ALS) technology, which offers lower propagation delay (typically 8 ns) and reduced power consumption compared to standard LS244 devices. Both sink 24 mA at the output (IOL), but ALS maintains performance at 4.5 V to 5.5 V with better noise margin and faster edges for 10 MHz or higher bus applications.
Can SN74ALS244CDB drive a 50 pF bus trace at 25 MHz without an external series termination resistor?
At 50 pF load capacitance and 24 mA drive, SN74ALS244CDB supports reliable switching at moderate bus speeds. For traces longer than about 10 cm or at clock rates approaching 25 MHz, a 22 ohm to 33 ohm series termination resistor at the output is recommended to damp reflections, as the ALS output impedance alone may not be sufficient to prevent ringing on a 50 pF unterminated line.
How do the two independent enable inputs on SN74ALS244CDB simplify address and data bus separation on a single-board computer?
SN74ALS244CDB organizes its 8 channels into two 4-bit banks, each with its own active-low output-enable pin. This allows address bits A0–A3 and A4–A7 to be enabled or tri-stated independently, so a CPU can use one bank for memory addressing while the other is isolated during I/O cycles — all within a single 20-pin SOIC-20 device without needing two separate quad-buffer ICs.
Related Guides
EEEFK1E470P Selection Guide for 47 uF SMD Aluminum Electrolytic Capacitors
Selection guidance for EEEFK1E470P and nearby Panasonic FK or FT SMD aluminum electrolytic capacitors for power-rail bulk decoupling.
Jul 7, 2026
EEEFT1V101AP Design Guide for SMD Aluminum Electrolytic Bulk Decoupling
Design guidance for using EEEFT1V101AP as an SMD aluminum electrolytic bulk capacitor in power-rail decoupling and hold-up networks.
Jul 7, 2026
How to Choose a 3528 SMD Indicator LED for Blue Status Lighting: Selection Guide
A practical 3528 SMD indicator LED selection guide using 150141BS73100 and related Wurth 150141 variants for blue status lighting.
Jul 5, 2026
BAS70KFILM Design Guide for Low-Leakage Signal Clamping and RF Detector Inputs
Practical BAS70KFILM design guidance for signal clamps, RF detector inputs, leakage control, capacitance, layout, and sourcing alternatives.
Jul 5, 2026
Why Buy from FindMyChip
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.
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
“Their engineering team helped us find a pin-compatible alternative when our original MCU went EOL.”