Diodes Incorporated DN350T05-7

Overview

DN350T05 from Diodes Incorporated is a 350V NPN small-signal surface-mount transistor in SOT23 package, rated for 500mA continuous collector current and 300mW power dissipation, with V_CEO = 350V, h_FE = 20–200 (IC = 1–100mA), and f_T = 50MHz - ideal for medium-power switching and amplification in industrial power supplies and LED drivers.

For engineers reviewing the DN350T05 datasheet, DN350T05 pinout, DN350T05 application, or DN350T05 equivalent, key selection considerations include its AEC-Q101 qualification, high-voltage breakdown capability (V_CEO/V_CBO = 350V), low saturation voltage (V_CE(SAT) ≤ 0.50V at IC = 30mA), and green RoHS-compliant construction.

Technical Context

This NPN bipolar junction transistor uses epitaxial planar die construction to achieve stable high-voltage operation up to 350V with low leakage (ICBO ≤ 50nA at VCB = 250V) and controlled gain dispersion (h_FE = 20–200 across IC = 1–100mA). Its thermal resistance R_θJA = 417°C/W reflects standard SOT23 mounting on FR4 with 1oz copper.

The device operates across –65°C to +150°C and supports fast switching via f_T = 50MHz at V_CE = 10V, IC = 20mA, while maintaining low C_obo = 7.0pF at V_CB = 20V - enabling use in flyback snubbers and high-side switch drivers where voltage robustness and capacitance control are critical.

Key Specifications

Pinout & Package

Package: SOT23 - surface-mount plastic case, 0.008g weight, UL 94V-0 rated, moisture sensitivity level 1, matte tin-plated leads solderable per MIL-STD-202 Method 208.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZTX653 and MMBT5551, DN350T05 uniquely balances 350V breakdown, SOT23 footprint, and AEC-Q101 qualification - making it optimal for space-constrained, high-reliability, medium-voltage switching where thermal budget and regulatory compliance are jointly critical.

Availability

DN350T05-7 is available at Aetrix Electronics and suitable for industrial power supplies, automotive lighting control, LED driver circuits, and AC line-sensing switches requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for DN350T05-7 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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

DN350T05 belongs to Diodes' high-voltage bipolar transistor product line, engineered specifically for reliable switching and amplification in cost-sensitive, space-constrained industrial and automotive applications where voltage margin and environmental compliance are mandatory.

FAQ

Is DN350T05-7 pin-compatible with standard SOT23 NPN transistors?

Yes - DN350T05-7 uses the industry-standard SOT23 pinout (Emitter-Base-Collector on pins 1-2-3), matching JEDEC TO-236AB. It is mechanically and electrically compatible with other SOT23-packaged NPN transistors, though electrical parameters (especially V_CEO and h_FE) differ and must be verified in-circuit.

What is the maximum safe operating temperature for DN350T05-7?

The DN350T05-7 has an absolute maximum junction temperature of +150°C and storage temperature range of –65°C to +150°C. At 25°C ambient, its 300mW power limit drops linearly with rising temperature, reaching zero dissipation at ~105°C ambient due to R_θJA = 417°C/W.

Does DN350T05-7 require a base resistor in switching applications?

Yes - a current-limiting base resistor is required to set appropriate I_B for desired I_C and ensure saturation. For example, to achieve I_C = 30mA with h_FE(min) = 20, I_B ≥ 1.5mA is needed; with V_BE(SAT) ≈ 0.8V and 3.3V GPIO drive, R_B ≈ 1.7kΩ.

Can DN350T05-7 replace MMBT2222A in existing designs?

No - MMBT2222A has V_CEO = 40V and is unsuitable for 350V applications. DN350T05-7 is not a drop-in replacement. It can replace lower-voltage transistors only after verifying layout clearance, thermal design, and drive requirements match its higher voltage and different gain profile.