Texas Instruments SN74F374DBR

Overview

SN74F374DBR from Texas Instruments is an 8-bit edge-triggered D-type flip-flop IC with 3-state bus-driving outputs, designed for high-capacitance or low-impedance bus interfacing. It features positive-edge clock triggering, buffered output enable (OE), and operates over 0°C to 70°C with V_CC = 4.5–5.5 V. It is used in I/O port buffering, bidirectional bus drivers, and working registers in legacy digital systems.

For engineers reviewing the SN74F374DBR datasheet, SN74F374DBR pinout, SN74F374DBR application, or SN74F374DBR equivalent, this page delivers verified electrical specs, SSOP-20 package details, timing parameters (t_PLH/t_PHL ≤ 10 ns), output drive capability (I_OL = 24 mA), and real-world use cases in industrial control backplanes and memory-mapped peripheral interfaces.

Technical Context

The SN74F374DBR implements eight independent D-type flip-flops sharing a common clock (CLK) and output enable (OE) input. Each flip-flop captures data on the rising edge of CLK and holds it until the next clock transition, while OE independently controls all eight outputs' high-impedance state without affecting internal storage.

Its TTL-compatible inputs accept VIH ≥ 2 V and VIL ≤ 0.8 V; outputs deliver VOH ≥ 2.4 V at IOH = −3 mA and VOL ≤ 0.35 V at IOL = 24 mA. Propagation delays are specified under CL = 50 pF and RL = 500 Ω, with t_PZH ≤ 12.5 ns and t_PLZ ≤ 6.5 ns for OE-controlled output transitions.

Key Specifications

Pinout & Package

SN74F374DBR uses a 20-pin Shrink Small-Outline Package (SSOP-20, DB package), measuring 7.5 mm × 5.6 mm × 2.0 mm max height, RoHS-compliant with NiPdAu lead finish and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type latch applications.

Compared with SN74F374DBR, SN74F373DBR trades edge-triggered reliability for simpler enable control, while SN74ACT374DBR offers superior speed and efficiency at the cost of process-family compatibility - both require schematic and timing validation before substitution.

Availability

SN74F374DBR is available at Aetrix Electronics and suitable for industrial backplane interfaces, microcontroller I/O expansion, memory-mapped peripheral bridges, and legacy ISA bus data latching requiring stable component supply and long-term obsolescence management.

Supply support for SN74F374DBR 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 founded in 1930, specializing in analog, embedded processing, and logic solutions with deep heritage in TTL and advanced logic families.

The SN74F374DBR belongs to TI's 74F (Fast TTL) logic family, engineered for high-speed, robust performance in industrial and computing infrastructure where deterministic timing and bus-driving strength are critical.

FAQ

What is the maximum clock frequency supported by the SN74F374DBR?

The SN74F374DBR supports a maximum clock frequency of 70 MHz under recommended operating conditions (V_CC = 4.5–5.5 V, T_A = 0°C to 70°C). This is validated by t_w(CLK high/low) ≥ 7/6 ns and t_PLH/t_PHL ≤ 10 ns, making SN74F374DBR suitable for high-speed synchronous bus applications such as ISA-compatible peripherals and FPGA-to-legacy interface bridges.

Does the SN74F374DBR support 3.3-V logic interfacing?

No, the SN74F374DBR is a 5-V Fast TTL device with VIH(min) = 2.0 V and VIL(max) = 0.8 V - it is not 3.3-V tolerant. Driving its inputs from 3.3-V logic may result in marginal or invalid high-level recognition. For mixed-voltage systems, level-shifting circuitry or a 3.3-V-compatible alternative like SN74ACT374DBR is required. SN74F374DBR must be powered from a stable 5-V rail.

How does the output enable (OE) function interact with internal flip-flop operation in the SN74F374DBR?

In the SN74F374DBR, the OE input affects only the output drivers - it has no effect on internal flip-flop state or data capture. While OE is asserted (low), Q outputs enter high-impedance mode, but D inputs remain fully functional: new data can be clocked in via CLK, and previously stored data remains intact. This allows seamless bus arbitration and asynchronous register updates without disrupting internal logic.

What package type and dimensions does the SN74F374DBR use?

The SN74F374DBR uses a 20-pin Shrink Small-Outline Package (SSOP-20), designated DB. Its footprint measures 7.5 mm × 5.6 mm with 0.65-mm lead pitch and maximum height of 2.0 mm. The package is RoHS-compliant with NiPdAu lead finish and MSL Level-1 rating, enabling standard reflow assembly without moisture preconditioning.

Can the SN74F374DBR drive standard TTL loads directly?

Yes, the SN74F374DBR is designed to drive standard TTL loads directly: it sources up to −3 mA (VOH ≥ 2.4 V) and sinks up to 24 mA (VOL ≤ 0.35 V), meeting or exceeding LS-TTL fan-out requirements (≥10 LSTTL loads). Its 3-state outputs also prevent bus contention, eliminating the need for external pull-up resistors or bus buffers in properly designed 5-V TTL systems.