SN74ABT244APWRE4 - Octal 3-State Buffer 5V TSSOP-20 | TI
部品番号: SN74ABT244APWRE4 ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $0.72 | $0.72 |
| 10 | $0.62 | $6.20 |
| 100 | $0.48 | $48.00 |
| 500 | $0.39 | $195.00 |
| 1,000 | $0.33 | $330.00 |
SN74ABT244APWRE4 概要
A buffer and line driver is a digital logic device that provides signal amplification, fan-out expansion, and isolation between a low-drive controller and high-capacitance loads. Within the logic hierarchy, line drivers sit between simple gates and full bus transceivers, providing unidirectional buffering with output enable control for bus-oriented systems. The 244 configuration is the industry-standard octal non-inverting buffer pinout.
Key features include Advanced BiCMOS (ABT) EPIC-II process technology that significantly reduces power dissipation compared to earlier bipolar families, 3-state outputs that allow direct connection to shared bus lines, and separate active-low OE1 and OE2 pins controlling the two 4-bit halves independently. Outputs are rated for high capacitive drive, making the part ideal for memory address driving and clock distribution. According to TI, the family targets 3-state memory address drivers, clock drivers, and bus-oriented receivers and transmitters.
The ABT architecture combines CMOS input logic with bipolar output transistors, giving the device TTL-compatible CMOS inputs, fast propagation delays, and robust output current capability at 5V operation. The PW package offers a compact 6.4 mm body with 0.65 mm pin pitch for space-constrained boards.
Typical applications include 5V microprocessor bus buffering, memory address and data line driving, industrial I/O module isolation, and backplane driver stages in legacy 5V systems.
For design, tie unused OE inputs to VCC through a pull-up to keep outputs in the high-impedance state during power-up, and decouple VCC with 0.1 uF ceramics.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in the manufacturer datasheet alone.
ドロップイン代替品: SN74ABT244APWRE4 — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: SN74ABT244APWRE4 （同一形状・フットプリント） — 相違点: Package, Input Type, Logic Function, Output Enable, RoHS Status.
クイック比較ツール — 並列比較する代替部品を選択:
SN74ABT244APWR
✅ ドロップイン✓ 在庫あり
$0.48 / 個
データシートを見る →SN74ABT244APWG4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
SN74ABT244APWRG4
✅ ドロップイン✓ 在庫あり
$0.38 / 個
データシートを見る →SN74ACT244APWR
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
SN74AHCT244APWR
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
SN74ABT244APWRE4 最大定格＆電気的特性
| Logic Family | ABT (Advanced BiCMOS) |
| 機能 | Octal buffer/driver, non-inverting |
| Number of Channels | 8 (2 elements x 4 bits) |
| Supply Voltage Range | 4.5 V to 5.5 V |
| 出力タイプ | 3-state |
| Polarity | Non-inverting |
| Input Type | TTL-compatible CMOS inputs |
| Output Enable | 2 active-low OE pins (/OE1, /OE2) |
| 動作温度 | -40C to +85C |
| パッケージ | TSSOP-20 (PW) |
| 実装タイプ | Surface Mount |
| ピン数 | 20 |
| Marking Code | AB244A |
| Typical Application | 3-state memory address drivers, clock drivers, bus receivers/transmitters |
| Process Technology | EPIC-II BiCMOS (Widebus family member per distributor listing) |
SN74ABT244APWRE4 ピン構成
| ピン 1 | /OE1 — Output enable 1, active low (controls outputs 1Y1-1Y4) |
| ピン 2 | 1A1 — Input A1, element 1 |
| ピン 3 | 2Y1 — Output Y1, element 2 (3-state) |
| ピン 4 | 1A2 — Input A2, element 1 |
| ピン 5 | 2Y2 — Output Y2, element 2 (3-state) |
| ピン 6 | 1A3 — Input A3, element 1 |
| ピン 7 | 2Y3 — Output Y3, element 2 (3-state) |
| ピン 8 | 1A4 — Input A4, element 1 |
| ピン 9 | 2Y4 — Output Y4, element 2 (3-state) |
| ピン 10 | GND — Ground |
| ピン 11 | 2A1 — Input A1, element 2 |
| ピン 12 | 1Y1 — Output Y1, element 1 (3-state) |
| ピン 13 | 2A2 — Input A2, element 2 |
| ピン 14 | 1Y2 — Output Y2, element 1 (3-state) |
| ピン 15 | 2A3 — Input A3, element 2 |
| ピン 16 | 1Y3 — Output Y3, element 1 (3-state) |
| ピン 17 | 2A4 — Input A4, element 2 |
| ピン 18 | 1Y4 — Output Y4, element 1 (3-state) |
| ピン 19 | /OE2 — Output enable 2, active low (controls outputs 2Y1-2Y4) |
| ピン 20 | VCC — Power supply, 4.5 V to 5.5 V |
主な用途
SN74ABT244APWRE4 の用途: 6 件s: 5V Microprocessor Bus Buffering, Memory Address and Clock Line Driving, Industrial I/O Module Isolation, Bus-Oriented Receiver and Transmitter Systems, Legacy 5V System Maintenance and Repair, Level-Loaded Clock Distribution.
5V Microprocessor Bus Buffering
The SN74ABT244APWRE4 buffers address, data, and control lines between a 5V processor and the rest of the system. The ABT BiCMOS output stage supplies the current needed to charge long, heavily capacitive backplane traces, while TTL-compatible CMOS inputs connect directly to processor buses without level shifting. Each 4-bit half is controlled by its own /OE pin, letting firmware tri-state segments of the bus during DMA or boot phases. Typical implementation places the buffer near the processor socket with 0.1 uF decoupling per package and 22-33 ohm series resistors on long lines to control ringing. Compared to CMOS-family buffers, the bipolar output stage holds signal edges fast under full load, protecting setup and hold margins.
おすすめ
Memory Address and Clock Line Driving
TI positions the SN74ABT244A family explicitly for 3-state memory address drivers and clock drivers. Memory arrays present large distributed capacitance on address lines; the ABT output stage's bipolar pull-up/pull-down transistors maintain fast, symmetrical edges under this load, preserving access-time margins. The 3-state outputs allow multiple bus masters to share address lines during refresh or DMA cycles. In a typical SRAM or DRAM subsystem, one SN74ABT244APWRE4 drives eight address lines with /OE tied to the bus-arbitration signal. Designers should keep clock-driven outputs terminated at the load end and verify propagation delay against the memory's setup window using the datasheet timing tables.
おすすめ
Industrial I/O Module Isolation
In PLC and industrial I/O modules that still run 5V logic, the SN74ABT244APWRE4 isolates field-facing circuitry from the controller's delicate bus pins. Its -40C to +85C operating range covers industrial cabinet environments, and the TSSOP-20 package fits dense I/O carrier boards. Tri-state capability lets a module release the shared backplane when addressed off, preventing bus contention between cards. The ABT family's reduced power dissipation - a stated design goal of TI's EPIC-II BiCMOS process - lowers cabinet heat versus older bipolar drivers. Place the buffer at the backplane connector edge, add TVS protection on field-side lines, and pull /OE pins up so outputs stay tri-stated during power sequencing.
おすすめ
Bus-Oriented Receiver and Transmitter Systems
TI's datasheet category for this device includes bus-oriented receivers and transmitters. In a bidirectional point-to-point link built from two unidirectional 244 buffers, one SN74ABT244APWRE4 handles the forward path and a second handles the reverse path, with /OE providing direction control managed by the bus controller. This arrangement avoids the added latency and complexity of a transceiver while keeping the standard 244 footprint. The strong ABT output stage supports multi-drop lines when only one driver is enabled at a time. Designers must guarantee that enables are interlocked so the two drivers on a line are never active simultaneously, typically with a non-overlapping enable signal from the controller logic.
おすすめ
Legacy 5V System Maintenance and Repair
Many installed systems - test instruments, telecom line cards, and defense electronics - are built around 5V TTL buses and require exact-form-fit-function replacements when repairing. The SN74ABT244APWRE4 with its industry-standard 244 TSSOP-20 pinout is a direct fit for these boards, and the identical SN74ABT244APWR alternate documented by Mouser simplifies procurement when the E4 suffix is out of stock. Because ABT is electrically compatible with the earlier bipolar 74S/74LS/74F 244 pinout family, it drops into designs originally drawn for older buffers while cutting power dissipation. Keep a few reels qualified with the G4 variants to hedge against long-term suffix availability changes.
おすすめ
Level-Loaded Clock Distribution
Distributing a master clock to multiple load banks stresses driver outputs; the SN74ABT244APWRE4's four-bit organization lets one package fan out a clock to eight destinations with two independent enables for zone-based clock gating. The ABT BiCMOS output gives crisp, low-skew edges into 15 pF test loads typical of distributed clock trees, and the 4.5V-5.5V tolerance absorbs supply rail sag on loaded boards. For best results, source-terminate each clock output with a series resistor matched to the trace impedance, keep all eight outputs on the same package to minimize part-to-part skew, and avoid routing clocks near the /OE control lines to prevent glitch-induced gating errors.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: SN74ABT244APWRE4 — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | SN74ABT244APWR | SN74ABT244APWG4 | SN74ABT244APWRG4 | SN74ACT244APWR | SN74AHCT244APWR |
|---|---|---|---|---|---|---|
| Package | TSSOP-20 (PW) | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Supply Voltage Range | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Logic Family / Output Stage | ABT (Advanced BiCMOS) | ABT (identical) | ABT (identical) | ABT (identical) | ACT (CMOS) | AHCT (CMOS) |
| Output Type | 3-state, non-inverting | 3-state, non-inverting | 3-state, non-inverting | 3-state, non-inverting | 3-state, non-inverting | 3-state, non-inverting |
| Relative Output Drive | Highest (BiCMOS bipolar stage) | Highest (identical die) | Highest (identical die) | Highest (identical die) | Lower (CMOS, approx. -20-30%) | Lower (CMOS, approx. -20-30%) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Ordering Suffix Meaning | E4 (RoHS-restructured designation), tape & reel | Standard tape & reel (Mouser-listed alternate) | G4 material designation | G4 material designation, tape & reel | Different family (ACT) | Different family (AHCT) |
主な差別化要因
- Highest output drive in the 244 pinout family （vs SN74ACT244APWR)
- Lower power dissipation than legacy bipolar 244 drivers （vs SN74ABT244APWR (vs 74F/74AS 244 parts))
- Procurement security through multiple equivalent order codes （vs SN74ABT244APWG4)
設計ノート
Estimated: with 8 outputs driving 50 pF loads at 20 MHz from 5V, dynamic power is roughly P = C*V^2*f*N = 50pF*25*20MHz*8 = 0.2 W, plus ABT static current per datasheet. Provide a 0.1 uF ceramic within 3 mm of pin 20 plus one bulk capacitor per package group. Because the bipolar output stage draws crowbar current during switching, undersized decoupling shows up as ground bounce on adjacent quiet outputs.
Route the /OE1 (pin 1) and /OE2 (pin 19) control traces away from the output lines they control; a glitched enable during a bus transaction can cause contention damage on a shared backplane. Fit 10 kohm pull-ups on both /OE pins so outputs are tri-stated while the 5V rail ramps. Keep the interleaved input/output pin pairs short - the 244 pinout alternates A and Y pins, which invites crosstalk if traces run parallel.
For bus or clock lines longer than about 10 cm at ABT edge rates, add 22-33 ohm series termination at the driver output to damp reflections; for heavily loaded backplanes, use pull-up/pull-down Thevenin termination at the load end. Verify worst-case propagation delay (including load derating from the datasheet tables) against receiver setup times - ABT delay increases measurably with load capacitance above the 50 pF test condition.
Do not substitute the LVC244 on a 5V rail without reviewing the datasheet - the LVC family is specified for 3.3V operation (5V-tolerant inputs only). Ensure only one driver is enabled on a shared line at any time; overlapping enables cause output-stage contention and possible device failure. The TSSOP-20 has a 0.65 mm pitch: confirm reflow profile and stencil design for fine-pitch assembly to avoid bridging between pins 10 and 11.
コンプライアンス情報
The E4 suffix historically denotes TI's RoHS-restructured part numbering, but explicit compliance status was not stated in the retrieved data; verify on ti.com/product/SN74ABT244A under Quality & Packaging.
