Diodes Incorporated MJD31CQ-13

Overview

MJD31CQ-13 from Diodes Incorporated is a 100V NPN bipolar junction transistor (BJT) in TO252 (DPAK) package, rated for 3A continuous collector current and 100V V_CEO, qualified to AEC-Q101 for automotive power switching applications including DC motor drivers and LED lighting ballasts.

For engineers reviewing the MJD31CQ-13 datasheet, MJD31CQ-13 pinout, MJD31CQ-13 application, or MJD31CQ-13 equivalent, key selection criteria include high-voltage blocking capability, thermal performance on PCB copper area, complementary PNP pairing with MJD32CQ, and automotive-grade reliability validation under JEDEC J-STD-020 moisture sensitivity Level 1.

Technical Context

This NPN BJT operates as a high-voltage, medium-power switch with V_CEO = 100 V and I_C = 3 A continuous rating. Its h_FE ranges from 25–50 at I_C = 1 A and drops to 10–50 at I_C = 3 A, supporting stable gain across load conditions.

V_CE(sat) ≤ 1.2 V at I_C = 3 A and I_B = 375 mA ensures low conduction loss in switching topologies. Thermal resistance R_θJA is 32 °C/W with 50 mm × 50 mm 2 oz copper, enabling operation up to +150 °C junction temperature in thermally constrained automotive environments.

Key Specifications

Pinout & Package

Package: TO252 (DPAK), surface-mount, with exposed collector pad for thermal conduction and mechanical anchoring. Molded green compound, UL 94V-0 rated, matte tin-plated leads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage NPN transistor applications.

Compared with ZTX653 and MJD31CUQ, MJD31CQ-13 delivers automotive-grade reliability in a thermally optimized TO252 package while maintaining active production status - making it the preferred choice for new automotive and industrial power-switching designs requiring long-term supply assurance.

Availability

MJD31CQ-13 is available at Aetrix Electronics and suitable for automotive motor control, LED lighting ballasts, industrial OR-ing circuits, and 48 V telecom backup switching requiring stable component supply and AEC-Q101 compliance.

Supply support for MJD31CQ-13 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 components for automotive, industrial, and consumer markets since 1960.

MJD31CQ belongs to Diodes' AEC-Q101-qualified high-voltage BJT product line, engineered specifically for robust power switching in harsh automotive environments with emphasis on thermal performance and transient survivability.

FAQ

Is MJD31CQ-13 suitable for high-frequency switching applications?

No - its f_T is 3.0 MHz at I_C = 500 mA, limiting practical use to frequencies below 100 kHz. It is optimized for medium-speed power switching (e.g., PWM motor control at 20–50 kHz), not RF or fast digital logic. Base drive must account for minority-carrier storage time to avoid slow turn-off.

What is the minimum recommended PCB copper area for thermal performance?

For full 3.9 W power dissipation, Diodes specifies a 50 mm × 50 mm area of 2 oz copper connected to the exposed collector pad. With 25 mm × 25 mm 1 oz copper, R_θJA rises to 59 °C/W - requiring derating to ~2.1 W. Minimum recommended pad (MRP) yields R_θJA = 80 °C/W and limits usable power to ~1.6 W.

Can MJD31CQ-13 replace MJD31CUQ in existing designs?

Yes - MJD31CQ-13 is the designated replacement for MJD31CUQ, sharing identical electrical specifications, TO252 package, pinout, and AEC-Q101 qualification. The "NOT RECOMMENDED FOR NEW DESIGN USE" note applies only to MJD31CUQ; MJD31CQ-13 is actively supported with full production and long-term availability.

Does MJD31CQ-13 require external base current limiting in switching applications?

Yes - with h_FE ranging from 10–50, base current must be sized to ensure saturation across temperature and process variation. At I_C = 3 A, a minimum I_B of 375 mA is required per datasheet; typical designs use 500–600 mA with a series resistor or active driver to guarantee hard saturation and minimize V_CE(sat) drift.