Texas Instruments SN75453BDRG4

Overview

SN75453BDRG4 from Texas Instruments is a dual OR-gate peripheral driver IC with open-collector npn outputs, designed for high-current (up to 300 mA per channel), high-voltage (up to 30 V) switching in TTL-compatible systems. It operates from 4.75 V to 5.25 V over 0°C to 70°C and features diode-clamped inputs, latch-up immunity at 20 V, and propagation delays as low as 18 ns.

For engineers reviewing the SN75453BDRG4 datasheet, SN75453BDRG4 pinout, SN75453BDRG4 application, or SN75453BDRG4 equivalent, key selection criteria include its OR logic function, SOIC-8 package thermal performance (RθJA = 122.2°C/W), output saturation voltage (VCE(sat) ≤ 0.8 V @ 300 mA), and compatibility with 3.3-V/5-V logic interfaces driving lamps, LEDs, or relays.

Technical Context

The SN75453BDRG4 implements two independent OR gates whose outputs drive internal npn transistors with emitter-connected to GND and collector exposed as open-drain outputs (1Y, 2Y). Each gate accepts TTL-level inputs (VIH ≥ 2 V, VIL ≤ 0.8 V) and provides logic-high output only when both inputs are low - otherwise it pulls output low via saturated transistor conduction.

Its design eliminates latch-up risk under transient overvoltage (no latch-up at 20 V after conducting 300 mA), supports fast switching (tPLH/tPHL ≤ 25 ns typical @ 5 V, 25°C), and uses on-chip base resistors (1.6 kΩ, 4 kΩ) to ensure stable biasing without external components.

Key Specifications

Pinout & Package

SN75453BDRG4 is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.90 mm, with standard JEDEC MS-012AC footprint and RoHS-compliant NiPdAu lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN75451BD (AND) and ULN2003ADR (Darlington), SN75453BDRG4 uniquely integrates OR logic with fast, low-saturation switching - making it optimal for direct TTL-to-high-current OR decision paths without added logic or speed penalty.

Availability

SN75453BDRG4 is available at Aetrix Electronics and suitable for industrial control panels, LED signage, instrumentation interfaces, and memory subsystems requiring stable component supply and long-term production continuity.

Supply support for SN75453BDRG4 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 to replace legacy SN75450-series drivers with improved latch-up immunity and tighter parametric control - targeting cost-sensitive, high-reliability peripheral interfacing in commercial-grade systems.

FAQ

What logic function does the SN75453BDRG4 implement?

The SN75453BDRG4 implements two independent 2-input OR gates (positive logic: Y = A + B) with open-collector npn outputs. When either input A or B is high, the corresponding output transistor saturates and pulls the output low; only when both inputs are low does the output remain high (via external pull-up). This behavior is confirmed in Table 8-3 and Figure 8-7 of the official TI datasheet for SN75453BDRG4.

Can SN75453BDRG4 drive a 24-V relay directly?

Yes, SN75453BDRG4 can drive a 24-V relay directly using its open-collector outputs. Connect the relay coil between the 24-V supply and the 1Y or 2Y pin; the IC sinks up to 300 mA with VCE(sat) ≤ 0.8 V at that current. A flyback diode must be placed across the coil. This capability is specified in Absolute Maximum Ratings (VO = 30 V) and Electrical Characteristics (VOL ≤ 0.8 V @ 300 mA) for SN75453BDRG4.

What is the recommended bypass capacitor for SN75453BDRG4?

A 0.1-µF ceramic capacitor is recommended between VCC and GND, placed as close as possible to the SN75453BDRG4 SOIC-8 package pins. This value is explicitly stated in Section 10 ("Power Supply Recommendations") of the SN75453BDRG4 datasheet to suppress supply noise and prevent logic glitches during high-current switching transitions.

Does SN75453BDRG4 require external base resistors?

No, SN75453BDRG4 does not require external base resistors. Its internal schematic (Figure 8-11) shows integrated 1.6-kΩ and 4-kΩ resistors providing proper biasing for the npn output transistors. This eliminates external components and ensures stable turn-on/turn-off behavior across temperature - a key feature documented in the "Feature Description" section of the SN75453BDRG4 datasheet.

Is SN75453BDRG4 compatible with 3.3-V microcontrollers?

Yes, SN75453BDRG4 is compatible with 3.3-V microcontrollers. Its TTL-compatible inputs accept VIH ≥ 2.0 V and VIL ≤ 0.8 V, which aligns with 3.3-V logic high levels (typically 2.4–3.3 V). The SN75453BDRG4 datasheet confirms this in Section 6.2 ("Recommended Operating Conditions") and notes diode-clamped inputs simplify interface design without level shifters.