Texas Instruments SN74AHC240DGVR

Overview

SN74AHC240DGVR from Texas Instruments is an octal 3-state buffer/driver IC designed for bus-oriented data transmission, clock distribution, and memory address driving. It features dual 4-bit channels with independent output-enable controls (1OE, 2OE), 5.5V-tolerant inputs, 8mA output drive at 5V, and 3.6ns typical propagation delay (5V, CL=15pF). It operates across –40°C to 85°C in a 20-pin TSSOP package.

For engineers reviewing the SN74AHC240DGVR datasheet, SN74AHC240DGVR pinout, SN74AHC240DGVR application, or SN74AHC240DGVR equivalent, this page delivers verified electrical specs, functional mode behavior, thermal metrics (RθJA = 116.8°C/W), real-world noise immunity data, and validated alternative options for bus interface design.

Technical Context

The SN74AHC240DGVR implements two independent 4-bit non-inverting buffer sections, each controlled by its own active-low output-enable input (1OE and 2OE). When enabled, it drives A-inputs to Y-outputs with CMOS-compatible logic levels; when disabled, outputs enter high-impedance state to prevent bus contention.

It supports wide VCC range (2V–5.5V), exhibits 5.5V input overvoltage tolerance regardless of VCC, and delivers rail-to-rail output swing with VOL ≤ 0.36V (IOL = 4mA, VCC = 3V) and VOH ≥ 2.58V (IOH = –4mA, VCC = 3V). Its 1.5ns typical output skew (tsk(o)) ensures tight timing alignment across all eight outputs.

Key Specifications

Pinout & Package

SN74AHC240DGVR uses a 20-pin Thin Shrink Small Outline Package (TSSOP-PW) with 0.65mm pitch, 6.5mm × 6.4mm body size, and 1.2mm max height. Pin 1 is located at the top-left corner adjacent to the index area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74LVC240APWR, SN74AHC240DGVR offers wider supply flexibility and 5V input tolerance but lower drive strength; compared with 74AHC240PW,118, it shares identical timing, thermal, and electrical behavior-making it suitable for designs requiring TI-specific qualification or traceability.

Availability

SN74AHC240DGVR is available at Aetrix Electronics and suitable for industrial PLC backplanes, smartphone baseband subsystems, and network switch control planes requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74AHC240DGVR 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 for industrial, automotive, and communications markets.

The SN74AHC240 family targets high-density, low-power bus interface applications where precise timing control, voltage translation, and 3-state isolation are critical-especially in space-constrained consumer and infrastructure equipment.

FAQ

What is the maximum operating temperature for SN74AHC240DGVR?

The SN74AHC240DGVR is rated for operation from –40°C to +85°C ambient temperature. This range is specified in the Recommended Operating Conditions table and validated across all electrical parameters including propagation delay, output drive, and noise margins. The device's thermal resistance (RθJA = 116.8°C/W) must be considered in PCB layout to ensure junction temperature remains within safe limits under full load.

Does SN74AHC240DGVR support 5V logic inputs when powered from 3.3V?

Yes, SN74AHC240DGVR supports 5.5V-tolerant inputs regardless of VCC level. When powered from 3.3V, inputs may swing up to 5.5V without damage or clamping, enabling direct connection to 5V peripherals. This capability is explicitly confirmed in Section 5.3 (Recommended Operating Conditions) and eliminates the need for external level-shifting circuitry in mixed-voltage systems.

How does the output-enable functionality work on SN74AHC240DGVR?

SN74AHC240DGVR has two independent active-low output-enable inputs: 1OE controls Y1–Y4, and 2OE controls 2Y1–2Y4. When an OE pin is low, its corresponding four outputs drive the A-input values; when high, those outputs enter high-impedance state. This dual-OE architecture allows selective bus segmentation and avoids contention during multi-master arbitration-verified in Table 7-1 (Function Table) and Figure 7-1 (Logic Diagram).

What is the typical propagation delay of SN74AHC240DGVR at 3.3V supply?

At VCC = 3.3V and CL = 15pF, SN74AHC240DGVR exhibits 5.3ns typical tPLH/tPHL (input-to-output delay) and 6.6ns typical tPZH/tPZL (enable-to-output delay). These values are measured per Parameter Measurement Information (Section 6) and reflect real-world performance in high-speed digital interfaces such as memory address buses and FPGA configuration links.

Is SN74AHC240DGVR pin-compatible with other TSSOP-20 octal buffers?

SN74AHC240DGVR follows standard TSSOP-20 pinout defined in TI's PW package drawing and is pin-compatible with industry-standard octal 3-state buffers like 74AHC240PW,118 (NXP) and MC74VHC240DTG (ON Semiconductor). Pin mapping-including dual OE, interleaved A/Y, and corner-placed VCC/GND-is consistent across these variants, enabling direct substitution in existing layouts when electrical specifications align.