Diodes Incorporated DSS4140V-7

Overview

DSS4140V from Diodes Incorporated is a low V_CE(SAT) NPN bipolar junction transistor in SOT-563 package, rated for 40 V V_CEO, 1 A continuous collector current, and 600 mW power dissipation at 25°C ambient. It delivers 190 mV V_CE(SAT) at I_C = 1 A / I_B = 100 mA and exhibits f_T = 150 MHz, making it suitable for high-efficiency switching in compact DC-DC converters and load-switching circuits.

For engineers reviewing the DSS4140V datasheet, DSS4140V pinout, DSS4140V application, or DSS4140V equivalent, key selection criteria include verified V_CE(SAT) performance at 1 A, thermal resistance (R_θJA = 208 °C/W), SOT-563 footprint compatibility, and complementary PNP pairing with DSS5140V in ultra-small surface-mount designs.

Technical Context

This NPN transistor uses epitaxial planar die construction to achieve low saturation voltage and stable h_FE across temperature (300–900 at I_C = 1 mA; 75–200 at I_C = 1 A). Its 150 MHz f_T supports medium-frequency switching, while pulsed I_CRP = 2 A and I_CM = 3 A enable short-duration overload handling.

The device operates from −55°C to +150°C, with R_θJA = 208 °C/W on FR-4 PCB using minimum recommended pad layout. C_obo = 10 pF at V_CB = 10 V enables predictable high-speed turn-off behavior in hard-switched topologies.

Key Specifications

Pinout & Package

SOT-563 is a 6-pin ultra-small surface-mount package with dual emitter-collector configuration optimized for space-constrained switching applications. Pin 1 and Pin 2 are emitter terminals, Pin 3 is base, Pin 4 is collector, Pin 5 and Pin 6 are additional emitter terminals - enabling parallel emitter paths for reduced saturation resistance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DMN3020LSD-13 and DXT7050Q-7, DSS4140V provides superior 40 V breakdown margin and lowest V_CE(SAT) in its SOT-563 class, making it optimal for 5–24 V switched-mode power stages where BJT drive simplicity and voltage headroom are prioritized over MOSFET gate efficiency.

Availability

DSS4140V is available at Aetrix Electronics and suitable for DC-DC converters, portable load switches, H-bridge motor drivers, and LED current regulators requiring stable component supply and consistent low-V_CE(SAT) performance.

Supply support for DSS4140V 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.

The DSS4140V belongs to Diodes' low-saturation-voltage bipolar transistor product line, engineered specifically for space-constrained, high-efficiency switching applications in portable and industrial power systems.

FAQ

What is the maximum allowable junction temperature for DSS4140V?

The DSS4140V has an operating junction temperature range of −55°C to +150°C. Its absolute maximum T_J is 150°C; sustained operation above this threshold risks parametric shift and long-term reliability degradation. Derating begins at T_A > 25°C per the R_θJA = 208 °C/W curve in Figure 1.

Can DSS4140V be used in linear regulator applications?

Yes, DSS4140V can serve as a pass transistor in low-dropout linear regulators, provided power dissipation remains within 600 mW at 25°C ambient and thermal design accommodates R_θJA. Its V_BE(ON) = 1.1 V and h_FE stability support predictable base-current-based regulation up to 1 A output.

Is DSS4140V pin-compatible with other SOT-563 transistors?

DSS4140V follows standard SOT-563 mechanical dimensions and pin numbering (top view: 1–2–3–6–5–4), but its internal dual-emitter configuration (pins 1/2/5/6 = emitter) differs from conventional 3-pin SOT-563 BJTs. Layout must allocate four separate emitter pads; direct substitution without schematic and footprint review is not recommended.

Does DSS4140V require external base current limiting in switching mode?

Yes - because DSS4140V is a bipolar transistor, its base must be driven with current-limited source (e.g., series resistor or current-source driver). For 1 A collector current, 100 mA base drive is required; exceeding I_B(max) = 300 mA risks bond-wire failure. The datasheet specifies I_B = 100 mA for nominal saturation, not maximum rating.