Diodes Incorporated MMDT4401-7

Overview

MMDT4401-7 from Diodes Incorporated is a dual NPN small-signal transistor in SOT363 package, rated for 40V V_CEO, 600mA I_C, and 200mW power dissipation. It delivers h_FE = 20–300 across 100µA–500mA collector current, with V_CE(sat) ≤ 0.75V at I_C = 500mA/I_B = 50mA, and is optimized for low-power switching in portable battery management circuits.

For engineers reviewing the MMDT4401-7 datasheet, MMDT4401-7 pinout, MMDT4401-7 application, or MMDT4401-7 equivalent, key selection criteria include dual-NPN matching tolerance, SOT363 thermal resistance (625°C/W), ESD robustness (4kV HBM), and guaranteed h_FE minima at multiple bias points.

Technical Context

This dual NPN transistor uses epitaxial planar die construction to ensure consistent gain matching and low leakage (I_CEX ≤ 100nA at V_CE = 35V). Its ultra-small SOT363 footprint supports high-density PCB layouts while maintaining thermal performance via 1oz copper pad layout per JEDEC standards.

The device operates across –55°C to +150°C and features 6.5pF C_obo and 30pF C_ibo for predictable RF behavior up to 250MHz f_T. Saturation voltages are specified under two load conditions (150mA/15mA and 500mA/50mA), enabling accurate switch-loss estimation in digital logic interfaces and LED drivers.

Key Specifications

Pinout & Package

Package: SOT363 - ultra-small surface-mount plastic package with 6 terminals, 0.006g mass, and UL 94V-0 flammability rating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual NPN transistor applications.

Compared with DMN3026LSD-13 and MMDT3904-7-F, MMDT4401-7 uniquely balances 600mA switching capability, 250MHz bandwidth, and dual-transistor integration in SOT363-making it optimal for space-constrained, medium-current digital and analog functions where bipolar characteristics (e.g., linear gain control, predictable saturation) are required.

Availability

MMDT4401-7 is available at Aetrix Electronics and suitable for LED driver circuits, portable power switches, signal level shifters, and current mirror references requiring stable component supply and RoHS-compliant packaging.

Supply support for MMDT4401-7 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 components for industrial, computing, and consumer markets.

The MMDT4401-7 belongs to Diodes' small-signal transistor product line, engineered for compact, energy-efficient switching and amplification in space- and power-sensitive applications such as wearables, IoT sensors, and portable instrumentation.

FAQ

What is the maximum allowable junction temperature for MMDT4401-7?

The MMDT4401-7 has an operating junction temperature range of –55°C to +150°C. This rating is validated under steady-state conditions with the device mounted on a FR-4 PCB using the minimum recommended pad layout and 1oz copper. Derating begins above +25°C ambient, with full power (200mW) permitted only at T_A ≤ +25°C.

Can MMDT4401-7 be used in linear amplifier configurations?

Yes - its h_FE specification (20–300) across five collector current levels and 1.0–15kΩ h_ie input impedance support Class-A and Class-AB small-signal amplification. However, its 200mW power limit and lack of guaranteed linearity parameters (e.g., THD, f_T flatness) make it best suited for non-critical gain stages, not high-fidelity audio.

Is there an automotive-grade version of this part?

Yes - the MMDT4401Q is the AEC-Q101 qualified automotive variant, sharing identical electrical specifications and SOT363 packaging but tested to extended temperature (–40°C to +150°C) and reliability standards. It carries separate qualification documentation and ordering codes.

How does the SOT363 package affect thermal performance compared to SOT23?

SOT363 has higher thermal resistance (R_θJA = 625°C/W) than single-transistor SOT23 packages (~400°C/W) due to dual-die integration and shared thermal path. This requires careful layout: use of thermal vias under the exposed pad (if present), increased copper area, and avoidance of adjacent heat sources to maintain safe junction temperatures at full 600mA load.