Diodes Incorporated DRDC3105F-7

Overview

DRDC3105F-7 from Diodes Incorporated is a single-channel integrated solid-state DC relay driver in SOT23 package, designed to switch 3V–6V inductive loads (e.g., relays, solenoids) with internal Zener clamping at 6.6V, 500mA continuous output sink current, and guaranteed open-circuit off-state on input loss. It replaces discrete BJT + Zener + base resistor configurations in automotive lamp drivers and telecom line cards.

For engineers reviewing the DRDC3105F-7 datasheet, DRDC3105F-7 pinout, DRDC3105F-7 application, or DRDC3105F-7 equivalent, this device delivers verified inductive load switching with ESD protection (1kV HBM), AEC-Q101 qualification, and low 0.1µA off-state leakage - critical for reliable 5V relay control in space-constrained industrial and automotive modules.

Technical Context

The DRDC3105F-7 integrates a low-saturation NPN BJT with a monolithically integrated 6.6V Zener diode across the collector-emitter path. Its input stage accepts TTL/CMOS logic-level signals (Vin(on) ≤ 1.5V, Vin(off) ≥ 400mV) and provides current-limited drive (Iin = 0.7–1.6mA typ at 250mA output), ensuring compatibility with microcontrollers and logic gates.

It operates over –55°C to +150°C, features near-zero quiescent supply current in off-state (<0.1µA at 5.5V), and guarantees fail-safe shutdown: output transitions to high-impedance open-circuit when input is disconnected or below threshold - eliminating unintended coil energization during power-up/down or signal loss.

Key Specifications

Pinout & Package

SOT23-3 package: ultra-compact surface-mount outline (2.9mm × 1.3mm × 1.0mm), green molding compound (UL 94V-0), matte tin-plated leads, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar inductive load driver applications.

Compared with ULN2003A and NSS12201LT1G, the DRDC3105F-7 uniquely combines single-channel integration, built-in 6.6V Zener clamping, fail-safe open-circuit shutdown, and AEC-Q101 qualification - making it optimal for space-constrained, high-reliability 5V relay control where EMI and safety integrity are design priorities.

Availability

DRDC3105F-7 is available at Aetrix Electronics and suitable for automotive lamp drivers, telecom line card relays, and industrial process controllers requiring stable component supply, long lifecycle support, and RoHS-compliant sourcing.

Supply support for DRDC3105F-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, application-optimized components for automotive, industrial, and communications markets.

The DRDC3105 belongs to Diodes' Integrated Relay Driver product line, engineered specifically to replace discrete BJT/Zener/resistor combinations in 3–6V inductive load switching - prioritizing EMI reduction, fail-safe behavior, and AEC-Q101 compliance.

FAQ

What is the maximum inductive load power the DRDC3105F-7 can drive from a 5V supply?

The DRDC3105F-7 delivers up to 430mA continuous output sink current at V_CE = 0.25V, enabling 2.5W load drive (5V × 0.5A) with margin. At full 500mA absolute max rating, power dissipation remains within the SOT23's 310mW limit due to low saturation voltage - confirmed by Figure 6 and Absolute Maximum Ratings table.

Does the DRDC3105F-7 require an external flyback diode?

No. The device integrates a monolithic 6.6V Zener diode across its output terminals (OUT-to-GND), which actively clamps inductive kickback energy during turn-off. This eliminates the need for external flyback diodes, reduces PCB area by ~30%, and lowers system EMI - as verified in the "Features and Benefits" and Figure 7 of the datasheet.

How does the DRDC3105F-7 ensure fail-safe operation during MCU reset?

The DRDC3105F-7 guarantees open-circuit output when input voltage falls below 400mV (V_IN(OFF)), and its internal design forces the BJT into cutoff - even with floating or disconnected input. This prevents unintended relay activation during power-up, brown-out, or firmware crash, satisfying functional safety requirements in automotive and industrial control.

Is the DRDC3105F-7 compatible with 3.3V logic microcontrollers?

Yes. With V_IN(ON) ≤ 1.5V and input bias current of only 0.7–1.6mA, the DRDC3105F-7 reliably switches on using standard 3.3V GPIO outputs (e.g., STM32, PIC, ESP32). Its low threshold ensures full conduction even with logic-high tolerances and PCB trace resistance - validated in Figure 3 and Electrical Characteristics tables.