Texas Instruments SN75454BPS

Overview

SN75454BPS from Texas Instruments is a dual-peripheral NOR driver IC designed for high-current, high-speed switching in TTL-based systems. It delivers 300 mA per channel, supports up to 30 V output voltage, operates from 0°C to 70°C, features open-collector outputs with diode-clamped TTL-compatible inputs, and is used to drive lamps, LEDs, and high-voltage peripherals from low-power logic sources.

For engineers reviewing the SN75454BPS datasheet, SN75454BPS pinout, SN75454BPS application, or SN75454BPS equivalent, key selection criteria include its NOR logic function, 300 mA sink capability per channel, 30 V off-state output rating, SO package thermal performance (RθJA = 119.6°C/W), and compatibility with 5 V TTL input levels.

Technical Context

The SN75454BPS implements two independent NOR gates whose outputs drive internal NPN transistors in open-collector configuration. Each channel sinks current when both inputs are low (positive-logic NOR), enabling direct interface with inductive or resistive loads up to 30 V and 300 mA.

It uses integrated base-resistor networks (1 kΩ, 4 kΩ, 1.6 kΩ) to ensure stable transistor biasing without external components, eliminates latch-up risk at 20 V/300 mA, and maintains fast propagation delays (tPLH/tPHL ≤ 35 ns at 5 V, 25°C) for high-speed peripheral control.

Key Specifications

Pinout & Package

SN75454BPS is housed in an 8-pin SO (Small Outline) package with 6.20 mm × 5.30 mm body size, gull-wing leads, and surface-mount compatibility. Thermal resistance RθJA is 119.6°C/W, supporting moderate power dissipation in compact layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NOR driver applications.

Compared with SN75452BPS and SN75453BPS, the SN75454BPS provides native NOR functionality - eliminating external inverters in active-low enable architectures, reducing component count, and preserving timing margins in synchronous peripheral control.

Availability

SN75454BPS is available at Aetrix Electronics and suitable for lamp drivers, LED arrays, line drivers, and memory subsystems requiring stable component supply and long-term industrial availability.

Supply support for SN75454BPS 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, embedded processing, and connectivity solutions with emphasis on reliability, longevity, and industrial-grade performance.

The SN7545xB family was designed specifically for TTL-compatible peripheral interfacing - providing robust, high-current, logic-gated drivers that replace discrete transistor arrays while maintaining pin compatibility with legacy SN75450-series devices.

FAQ

What logic function does the SN75454BPS implement?

The SN75454BPS implements a dual NOR gate function: each channel's output (1Y or 2Y) sinks current only when both corresponding inputs (1A/1B or 2A/2B) are low. This active-low behavior makes SN75454BPS ideal for enable/disable control of peripherals where deactivation is the default state. The internal schematic confirms this using resistor networks and NPN transistors configured for positive-logic NOR operation.

Can SN75454BPS drive a 24 V relay coil directly?

Yes, SN75454BPS can drive a 24 V relay coil directly via its open-collector outputs. With a 30 V off-state voltage rating and 300 mA continuous sink capability per channel, it supports typical 24 V relay coils drawing ≤250 mA. An external pull-up resistor connects the 1Y or 2Y pin to +24 V, and the SN75454BPS sinks current when activated. Ensure the relay coil flyback diode is installed across the coil to protect the SN75454BPS output transistor.

What is the maximum allowable supply voltage for SN75454BPS VCC pin?

The maximum allowable supply voltage for the SN75454BPS VCC pin is 5.25 V, as specified in the Recommended Operating Conditions table. Exceeding this value risks exceeding absolute maximum ratings and may cause permanent damage. The device is optimized for 5 V TTL systems, with guaranteed operation between 4.75 V and 5.25 V. Supply decoupling with a 0.1 µF ceramic capacitor near the VCC pin is mandatory to suppress switching noise.

Does SN75454BPS require external base resistors for transistor biasing?

No, SN75454BPS does not require external base resistors. It integrates internal resistor networks (1 kΩ, 4 kΩ, and 1.6 kΩ) directly into each driver channel, as shown in the functional schematics (Figure 8-12). These resistors provide proper base biasing for the output NPN transistors, enabling reliable saturation and turn-off without additional components - simplifying design and reducing PCB footprint compared to discrete transistor solutions.

How does SN75454BPS prevent latch-up during high-current operation?

SN75454BPS prevents latch-up by design: its internal structure and process technology ensure freedom from latch-up even when conducting 300 mA at 20 V, as verified in the Absolute Maximum Ratings and Feature sections. This is achieved through isolation techniques and layout optimization that suppress parasitic SCR formation. Unlike some older bipolar drivers, SN75454BPS maintains safe operation under sustained high-current stress without requiring derating or special layout precautions beyond standard grounding and decoupling.