Texas Instruments SN75469DR

Overview

SN75469DR from Texas Instruments is a 7-channel high-voltage NPN Darlington transistor array with 500-mA per-channel sink capability, 100-V collector-emitter rating, integrated common-cathode clamp diodes, and 10.5-kΩ input base resistors optimized for direct interface with 6–15-V CMOS/PMOS logic. It serves as an industrial-grade relay, lamp, and solenoid driver in programmable logic controllers and factory automation I/O modules.

For engineers reviewing the SN75469DR datasheet, SN75469DR pinout, SN75469DR application, or SN75469DR equivalent, key selection criteria include its 10.5-kΩ input resistor value (vs. SN75468's 2.7-kΩ), 100-V output voltage rating, 500-mA continuous sink current per channel, thermal derating behavior in SOIC-16 package, and compatibility with inductive load flyback suppression via COM-connected clamp diodes.

Technical Context

The SN75469DR integrates seven independent NPN Darlington pairs sharing a common emitter (E) and a common cathode node (COM) for internal flyback diode clamping. Each channel uses a 10.5-kΩ series base resistor to limit input current-enabling direct drive from 6–15-V CMOS or PMOS logic without external biasing.

Its functional architecture supports parallel operation of outputs for higher current loads, operates over 0°C to 70°C ambient, and relies on the COM pin tied to the inductive load supply rail to activate internal clamp diode protection during turn-off transients. The device exhibits typical V_CE(sat) ≤ 1.6 V at I_C = 100 mA and I_I = 500 µA.

Key Specifications

Pinout & Package

SN75469DR is housed in a 16-pin SOIC (D) package measuring 9.90 mm × 3.91 mm with 1.27-mm lead pitch and gull-wing leads. The package is RoHS-compliant, moisture-sensitivity Level-1 rated, and supplied in 2500-unit tape-and-reel format (reel diameter 330 mm, width 16.4 mm).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Darlington array applications.

Compared with ULN2004A, SN75469DR delivers 2× higher voltage tolerance critical for 100-V industrial loads; compared with SN75468DR, it reduces input current by 73% at 12 V - extending battery life and easing drive requirements for low-power logic families.

Availability

SN75469DR is available at Aetrix Electronics and suitable for industrial automation, factory control systems, and embedded HMI design requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for SN75469DR 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 logic solutions for industrial, automotive, and communications markets.

The SN75469DR belongs to TI's legacy Darlington transistor array product line, designed specifically for robust, high-voltage, high-current interface between low-voltage logic and industrial electro-mechanical loads.

FAQ

What is the maximum continuous sink current per channel for SN75469DR?

The SN75469DR supports 500 mA continuous collector current per Darlington channel under recommended operating conditions (T_A ≤ 70°C, proper PCB copper pour). Derating is required above 70°C ambient; Figure 4 in the datasheet shows maximum current vs. duty cycle for the D-package variant. Exceeding 500 mA risks thermal shutdown or permanent damage to the SN75469DR.

How does SN75469DR differ from SN75468DR in terms of input drive requirements?

The SN75469DR uses a 10.5-kΩ internal base resistor per channel, drawing ~1.1 mA at 12 V, making it suitable for 6–15-V CMOS/PMOS logic. In contrast, SN75468DR uses a 2.7-kΩ resistor, drawing ~3.7 mA at 12 V - optimized for TTL and 5-V CMOS. This difference makes SN75469DR preferable for low-power or higher-voltage logic interfaces where input current must be minimized.

Can multiple outputs of SN75469DR be paralleled to increase current capacity?

Yes, SN75469DR channels can be paralleled to increase total sink current - e.g., two channels in parallel support up to 1 A. However, ensure matched trace lengths and thermal coupling to avoid current imbalance. The datasheet confirms this capability explicitly for higher-current relay or solenoid loads, and the shared emitter (E) pin simplifies parallel implementation in the SN75469DR.

What is the role of the COM pin on SN75469DR, and how must it be connected?

The COM pin on SN75469DR is the common cathode node for all seven internal clamp diodes. For inductive load protection, COM must be connected to the positive supply rail of the load (e.g., +24 V for a relay coil). If left unconnected or grounded, flyback energy cannot recirculate, risking voltage overshoot and potential damage to the SN75469DR or upstream circuitry.

Is SN75469DR compatible with 3.3-V logic inputs?

No - SN75469DR's 10.5-kΩ input resistor requires ≥6 V to reliably exceed the typical V_I(on) threshold of ~1.1 V (per datasheet Table 7.5). At 3.3 V, input current drops to ~0.3 mA, which may not fully saturate the Darlington pair. For 3.3-V logic, SN75468DR (2.7-kΩ resistor) or a level-shifting buffer is recommended instead of SN75469DR.