Diodes Incorporated 74AVC1T45DW-7

Overview

74AVC1T45DW-7 from Diodes Incorporated is a single-bit dual-supply translating transceiver with 3-state outputs, designed for bidirectional voltage-level translation between 1.2V and 3.6V domains. It features independent VCCA and VCCB supplies, direction-controlled data flow via DIR pin referenced to VCCA, and I_OFF protection enabling partial power-down isolation. It is used in mobile device interconnects where logic domains operate at mismatched voltages (e.g., 1.8V SoC ↔ 3.3V peripheral).

For engineers reviewing the 74AVC1T45DW-7 datasheet, 74AVC1T45DW-7 pinout, 74AVC1T45DW-7 application, or 74AVC1T45DW-7 equivalent, key selection criteria include dual-rail supply flexibility (1.2–3.6V each), ±12mA drive strength at 3.3V, 3-state timing (tpLZ/tpHZ ≤ 6.9ns), I_OFF leakage < ±0.1μA at 0V supply, and SOT363 package thermal resistance (θ_JA = 371°C/W).

Technical Context

The device implements a direction-controlled bidirectional buffer with separate input/output voltage references: A port tracks VCCA, B port tracks VCCB, and DIR is referenced to VCCA. Its I_OFF circuitry activates when either VCCA or VCCB drops to 0V, forcing both A and B into high-impedance while blocking backflow up to 3.6V.

Logic operation supports mixed-voltage signaling without level-shifting components: VIH/VIL thresholds scale with respective VCC rails (e.g., VIH(DIR) = 0.65×VCCA min), and output VOH/VOL are rail-referenced (VOH ≥ VCCO – 0.2V). Propagation delays (tpLH/tpHL) range from 2.2ns to 3.3ns depending on VCCA/VCCB combinations.

Key Specifications

Pinout & Package

SOT363 (6-pin small-outline transistor) package with exposed pad for thermal enhancement; footprint compatible with JEDEC MO-178AA standard. Pin 1 marked by notch or bevel; bottom view orientation matches datasheet Figure 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-bit dual-supply translating transceiver applications.

Compared with SN74AVC1T45DBVR and 74LVC1T45GW,125, the 74AVC1T45DW-7 uniquely supports 1.2V operation, achieves lowest I_OFF leakage (<0.1μA), and delivers fastest 3-state enable timing (≤6.9ns), making it optimal for battery-powered, multi-voltage, and partial-power-down architectures.

Availability

74AVC1T45DW-7 is available at Aetrix Electronics and suitable for mobile device interfaces, low-power peripheral bridges, and industrial sensor hubs requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for 74AVC1T45DW-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, specializing in high-performance, energy-efficient components for consumer, computing, industrial, and automotive markets.

The 74AVC logic family targets low-voltage, high-speed digital interfaces in space-constrained portable electronics, emphasizing rail-to-rail translation, ultra-low static current, and robust ESD performance.

FAQ

What is the maximum allowable voltage on the A or B pin when VCCA or VCCB is at 0V?

When either VCCA or VCCB is at 0V, the A and B pins tolerate up to 3.6V in high-impedance state due to I_OFF protection. This prevents damaging back-current flow and ensures electrical isolation between powered and unpowered domains, critical for hot-swap and partial-power-down operation.

Can the DIR pin be driven from a different voltage domain than VCCA?

No. The DIR pin is explicitly referenced to VCCA, and its VIH/VIL thresholds scale with VCCA (e.g., VIH = 0.65×VCCA). Driving DIR from VCCB or another rail risks incorrect direction control or latch-up; it must be sourced from the same domain as VCCA.

How does the 74AVC1T45DW-7 handle simultaneous VCCA and VCCB power-up sequencing?

The device operates correctly across all valid VCCA/VCCB combinations (1.2–3.6V each) regardless of ramp order. No strict power-up sequence is required; I_OFF activates automatically if one supply reaches 0V while the other is active, ensuring safe startup and shutdown behavior.

Is the SOT363 package thermally adequate for continuous 12mA output drive?

Yes. With θ_JA = 371°C/W and typical power dissipation <15mW at 12mA/3.3V, junction temperature rise remains <6°C above ambient under standard PCB layout (2oz copper, minimum pads), well within the –40°C to +150°C rating.