Texas Instruments SN75451BDE4

Overview

SN75451BDE4 from Texas Instruments is a dual-peripheral AND driver IC designed for high-current, high-speed switching in TTL-based systems. It delivers open-collector outputs with 300 mA continuous current capability, 30 V output voltage tolerance, and operates across 0°C to 70°C. It serves as a logic-level translator and peripheral power driver in industrial control interfaces.

For engineers reviewing the SN75451BDE4 datasheet, SN75451BDE4 pinout, SN75451BDE4 application, or SN75451BDE4 equivalent, key selection criteria include its AND-gate logic function, SOIC-8 package thermal performance (RθJA = 122.2°C/W), latch-up immunity at 20 V, and compatibility with 5 V TTL input thresholds.

Technical Context

The SN75451BDE4 integrates two independent AND-gate logic inputs driving NPN open-collector output transistors. Each channel features diode-clamped TTL-compatible inputs and internal base resistors enabling direct MCU interface without external biasing.

Its functional mode requires both inputs (1A/1B or 2A/2B) to be high for output conduction (low-state), delivering up to 300 mA per channel into loads referenced to VCC or external supplies up to 30 V. No internal latching occurs under transient overvoltage conditions up to 20 V.

Key Specifications

Pinout & Package

SN75451BDE4 uses an 8-pin SOIC (D) package measuring 4.90 mm × 3.90 mm with standard gull-wing leads. Thermal resistance is RθJA = 122.2°C/W, requiring minimal heatsinking for typical 300 mA loads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual AND-driver applications.

Compared with SN75451BP and SN75452BDE4, SN75451BDE4 offers surface-mount reliability and optimal thermal performance in SOIC-8 while preserving strict AND logic behavior - critical for deterministic enable/control paths in safety-aware systems.

Availability

SN75451BDE4 is available at Aetrix Electronics and suitable for industrial control interfaces, LED lighting subsystems, and legacy bus line drivers requiring stable component supply and long-term manufacturability.

Supply support for SN75451BDE4 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 connectivity technologies with over 90 years of innovation in industrial, automotive, and communications markets.

The SN7545xB family was engineered for TTL-system peripheral interfacing - delivering robust, latch-up-free high-current driving in cost-sensitive commercial applications where reliability and pin compatibility matter.

FAQ

What logic function does the SN75451BDE4 implement?

The SN75451BDE4 implements a dual AND gate function: each channel's output (1Y or 2Y) goes low (active) only when both corresponding inputs (1A and 1B, or 2A and 2B) are high. This behavior is confirmed in the device function table and logic diagram in the official TI datasheet. The SN75451BDE4 does not perform NAND, OR, or NOR functions - those are handled by other members of the SN7545xB family like SN75452BDE4 or SN75453BDE4.

Can SN75451BDE4 drive a 24 V relay coil directly?

Yes, SN75451BDE4 can drive a 24 V relay coil directly using its open-collector output configuration. Connect the relay coil between the 24 V supply and the SN75451BDE4 output pin (e.g., 1Y), with the coil's other terminal grounded. The SN75451BDE4 sinks up to 300 mA, sufficient for most 24 V/100–200 mA relays. Ensure the relay's flyback diode is installed across the coil to protect the SN75451BDE4 from inductive kickback.

What is the maximum allowable supply voltage for SN75451BDE4?

The SN75451BDE4 has a recommended VCC supply voltage range of 4.75 V to 5.25 V. Its absolute maximum VCC rating is 7 V, but operation outside the recommended range risks parametric failure or reduced reliability. The 30 V rating applies only to the off-state output voltage (VO), not the VCC pin - applying >5.25 V to VCC violates specifications and may damage the SN75451BDE4.

Does SN75451BDE4 require external pull-up resistors on its outputs?

Yes, SN75451BDE4 requires external pull-up resistors on its open-collector outputs (1Y and 2Y). Since the outputs can only sink current (pull low), a pull-up resistor to the desired load supply (e.g., 5 V, 12 V, or 24 V) is mandatory to establish a valid high logic level. The resistor value depends on load current and rise time requirements - typical values range from 1 kΩ to 10 kΩ. No pull-up is needed on inputs, as they are TTL-compatible with internal clamping.

Is SN75451BDE4 RoHS compliant and lead-free?

Yes, SN75451BDE4 is RoHS compliant and features Ni/Pd/Au (NIPDAU) lead finish, as documented in TI's official packaging addendum. It carries a Level-1 moisture sensitivity rating (MSL-1) with unlimited floor life at ≤30°C/60% RH, and is qualified for reflow soldering at peak temperatures up to 260°C. The "E4" suffix explicitly denotes TI's green packaging standard, confirming full compliance with EU RoHS Directive 2011/65/EU.