Texas Instruments SN74ALVC245DWR

Overview

SN74ALVC245DWR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between two 8-bit buses operating at 1.65 V to 3.6 V. It features ±24-mA drive strength at 3.3 V, 3.4-ns max propagation delay, and latch-up immunity exceeding 250 mA per JESD 17-used in voltage-level shifting and isolated bus communication in embedded control systems.

For engineers reviewing the SN74ALVC245DWR datasheet, SN74ALVC245DWR pinout, SN74ALVC245DWR application, or SN74ALVC245DWR equivalent, key selection criteria include direction-control logic behavior, 3-state output isolation timing (ten/tdis), supply voltage range compatibility, and SOIC-20 thermal performance (θJA = 58°C/W).

Technical Context

The SN74ALVC245DWR implements dual-rail CMOS logic with independent DIR and OE inputs governing data flow direction and output enable state. Its internal architecture supports true bidirectional operation: when OE is low, data propagates either A→B (DIR = high) or B→A (DIR = low); when OE is high, all outputs enter high-impedance state regardless of DIR.

It meets JESD 17 latch-up specifications (>250 mA), operates across 1.65–3.6 V VCC with input thresholds scaling proportionally (e.g., VIH = 0.65×VCC at 1.65 V), and delivers rail-to-rail output swing with VOH ≥ VCC − 0.2 V and VOL ≤ 0.55 V at 3 V/24 mA load.

Key Specifications

Pinout & Package

SN74ALVC245DWR uses a 20-pin SOIC (DW) package with 7.5-mm body width, 2.65-mm max height, and JEDEC MS-013 compliance. Pin 1 is located at the top-left corner with a beveled edge marker.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal bus transceiver applications.

Compared with SN74LVC245ADWR and 74AVC245T20-13, the SN74ALVC245DWR provides superior voltage-range flexibility (1.65–3.6 V), industry-leading latch-up immunity, and proven thermal performance in SOIC packaging-making it optimal for industrial and automotive applications requiring wide supply tolerance and reliability.

Availability

SN74ALVC245DWR is available at Aetrix Electronics and suitable for industrial PLC backplanes, low-power sensor hubs, embedded display bridges, and automotive body control modules requiring stable component supply across extended temperature ranges (−40°C to 85°C).

Supply support for SN74ALVC245DWR 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The SN74ALVC245DWR belongs to TI's ALVC (Advanced Low-Voltage CMOS) logic family, engineered for high-speed, low-voltage bidirectional bus interfacing in mixed-supply systems where power efficiency and signal integrity are critical.

FAQ

What is the recommended power-up sequence for SN74ALVC245DWR to avoid bus contention?

TI recommends tying OE to VCC through a pullup resistor (minimum value determined by driver sink capability) to ensure outputs remain in high-impedance state during power ramp-up. DIR may float initially but must be stabilized before OE is driven low. This prevents unintended data transfer or bus conflicts during VCC stabilization. The SN74ALVC245DWR datasheet specifies this sequence to guarantee safe initialization in systems with asynchronous power rails.

Can SN74ALVC245DWR operate reliably at 1.65 V VCC with full 8-bit data throughput?

Yes, SN74ALVC245DWR is fully specified down to 1.65 V VCC, including guaranteed tpd ≤ 6 ns, VIH = 0.65×VCC, and VOL ≤ 0.45 V at 4 mA load. All 8 channels maintain timing and drive specifications across the entire 1.65–3.6 V range, making SN74ALVC245DWR suitable for ultra-low-voltage IoT sensor nodes where battery voltage drops near 1.65 V.

How does the latch-up immunity of SN74ALVC245DWR compare to standard LVC transceivers?

SN74ALVC245DWR exceeds 250 mA latch-up immunity per JESD 17, significantly higher than baseline LVC devices (typically 200 mA). This enhanced robustness stems from TI's ALVC process optimization, allowing SN74ALVC245DWR to withstand larger transient currents in noisy industrial environments-such as motor drive EMI bursts-without functional interruption or permanent damage.

Is SN74ALVC245DWR pin-compatible with other 20-pin octal transceivers in SOIC packages?

SN74ALVC245DWR shares identical SOIC-20 (DW) mechanical dimensions and pinout with SN74LVC245A, SN74LVCH245A, and 74ALVC245 variants. However, electrical differences exist: ALVC offers wider VCC range and higher latch-up rating. Physical drop-in replacement is possible, but verify VIH/VIL thresholds and drive strength match your design's timing and loading requirements before substitution.

What is the maximum continuous output current per pin for SN74ALVC245DWR, and how does it affect thermal design?

SN74ALVC245DWR supports ±50 mA continuous output current per pin, though recommended operating conditions limit it to ±24 mA at 3.3 V for timing compliance. At full 24-mA drive across all 8 outputs, power dissipation reaches ~120 mW. With θJA = 58°C/W in SOIC-20, junction temperature rise is ~7°C above ambient-well within safe limits. No heatsink is needed, but ensure ≥1 cm² copper pour under the SN74ALVC245DWR for optimal thermal conduction.