Texas Instruments SN74AHC245DGVR

Overview

SN74AHC245DGVR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between two 8-bit buses. It operates from 2 V to 5.5 V, supports 5-V/3.3-V level translation, and features 20-pin TVSOP packaging with ±25 mA output drive per channel - used in PC motherboard I/O expansion and server memory subsystems.

For engineers reviewing the SN74AHC245DGVR datasheet, SN74AHC245DGVR pinout, SN74AHC245DGVR application, or SN74AHC245DGVR equivalent, key selection criteria include bidirectional direction control (DIR), active-low output enable (OE), 3.3-V/5-V mixed-voltage bus isolation, and TVSOP-20 thermal performance under industrial temperature range (–40°C to 125°C).

Technical Context

The SN74AHC245DGVR implements dual-bus transceiver logic with independent DIR and OE controls: DIR selects data flow direction (A→B or B→A), while OE places all outputs in high-impedance state for bus isolation. Its CMOS AHC-family architecture ensures rail-to-rail input tolerance up to 5.5 V regardless of VCC, enabling robust down-translation from 5 V to 3.3 V systems.

Propagation delays are specified at 1 ns (min) to 10 ns (max) under 15-pF load at 3.3 V, and 1 ns to 6.5 ns at 5 V; output transition rates are controlled (20–100 ns/V) to suppress ringing on lightly loaded PCB traces - critical for noise-sensitive telecom infrastructure backplanes and wearable device interconnects.

Key Specifications

Pinout & Package

SN74AHC245DGVR uses a 20-pin Thin Very Small Outline Package (TVSOP) with 0.5-mm pitch, 5.00 mm × 6.4 mm body size, and exposed thermal pad (RKS variant only - not applicable here). Pin 1 is DIR, pin 19 is OE, pins 2–9 and 11–18 are bidirectional A/B bus terminals, pin 10 is GND, and pin 20 is VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A and 74ALVC245, the SN74AHC245DGVR uniquely supports 5-V signaling without level shifters, delivers consistent timing across 2–5.5 V operation, and maintains industrial temperature rating - making it the only choice for mixed-voltage server and telecom backplane designs.

Availability

SN74AHC245DGVR is available at Aetrix Electronics and suitable for PC motherboards, network switches, and wearable health devices requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74AHC245DGVR 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The SN74AHC245DGVR belongs to TI's AHC logic family, engineered for high-speed, low-power, mixed-voltage bus interfacing in computing and communications infrastructure.

FAQ

What is the maximum supply voltage for SN74AHC245DGVR?

The SN74AHC245DGVR supports a maximum supply voltage of 5.5 V, with absolute maximum ratings extending to 7 V for short-duration transients. This 5.5-V rating enables safe operation in 5-V systems and provides margin for ripple and overshoot - a key requirement for SN74AHC245DGVR deployment in industrial power supplies and server VRMs.

Does SN74AHC245DGVR support 5-V to 3.3-V level translation?

Yes, SN74AHC245DGVR supports true 5-V to 3.3-V down-translation: its inputs tolerate up to 5.5 V regardless of VCC setting, allowing 5-V signals to be safely applied when VCC = 3.3 V. This eliminates external level-shifting components in SN74AHC245DGVR-based mixed-voltage interfaces such as USB hub controllers or PCIe endpoint bridges.

What is the thermal resistance (RθJA) of SN74AHC245DGVR in TVSOP package?

The junction-to-ambient thermal resistance (RθJA) for SN74AHC245DGVR in TVSOP (DGV) package is 116.1 °C/W, measured under JEDEC JESD51-2 conditions. This value reflects typical PCB layout with 1-inch² copper pour; actual thermal performance improves with enhanced heatsinking - critical for SN74AHC245DGVR use in thermally constrained network switch modules.

Can SN74AHC245DGVR outputs be paralleled for higher drive strength?

SN74AHC245DGVR outputs may be paralleled only if both channels share identical DIR and OE states and drive the same net - but this increases effective output capacitance and edge rate, potentially causing ringing. TI does not recommend paralleling for increased drive; instead, use SN74AHC245DGVR in standard configuration and select higher-drive alternatives like SN74AHCT245 if needed.

What is the recommended bypass capacitor for SN74AHC245DGVR?

A 0.1-µF ceramic capacitor placed as close as possible to the VCC pin (Pin 20) is the minimum recommended bypass for SN74AHC245DGVR. For optimal noise suppression in high-speed bus applications, TI recommends pairing it with a 1-µF capacitor in parallel - both mounted within 2 mm of the TVSOP package to minimize inductance and maintain SN74AHC245DGVR signal integrity.