onsemi NST4617MX2T5G

Overview

NST4617MX2T5G from onsemi is an NPN silicon general-purpose amplifier transistor in a 3-pin X2DFN3 (1.0 mm × 0.6 mm) surface-mount package, rated for 50 V V_(BR)CEO, 100 mA I_C, and 280 typical h_FE, optimized for compact audio preamplifier and signal buffering stages in space-constrained consumer electronics.

For engineers reviewing the NST4617MX2T5G datasheet, pinout, applications, or equivalent options, key selection criteria include its low 0.08 V typical V_CE(sat) at I_C = 60 mA/I_B = 5 mA, 112 MHz f_T, 1.7 pF C_OB, and thermal performance under 100 mm² copper pad layout per Note 2.

Technical Context

This discrete NPN bipolar junction transistor operates in linear amplification mode with verified DC current gain spanning 120–560 across I_C = 1.0 mA to 100 mA at V_CE = 6.0 V. Its transition frequency of 112 MHz (V_CE = 12 V, I_C = 2.0 mA) supports mid-band RF and wideband analog signal conditioning up to ~100 MHz.

The device features two distinct thermal derating profiles: 1.39 mW/°C on minimal 0.6 mm² Cu pad (R_JA = 722 °C/W), and 5.99 mW/°C on 100 mm² Cu pad (R_JA = 167 °C/W), enabling design flexibility between ultra-compact and thermally robust layouts.

Key Specifications

Pinout & Package

The NST4617MX2T5G is housed in the X2DFN3 (Case 714AC) 3-terminal surface-mount package measuring 1.0 mm × 0.6 mm with 0.35 mm pitch. It uses a bottom-exposed thermal pad for enhanced heat dissipation when soldered to ≥100 mm² copper area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose amplifier applications.

Compared with MMBT4401LT1G and BC846BPDW1T1G, the NST4617MX2T5G delivers superior low-current gain stability (120–560 h_FE range), tighter V_CE(sat) control (0.08 V typ), and optimal thermal resistance (167 °C/W) on standard 100 mm² pads-making it preferred for precision analog buffering where gain consistency and thermal headroom matter most.

Availability

NST4617MX2T5G is available at Aetrix Electronics and suitable for audio preamplifier stages, sensor signal buffering, and LED current driver circuits requiring stable component supply, consistent parametric performance, and RoHS-compliant packaging.

Supply support for NST4617MX2T5G 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

onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power and signal management solutions for automotive, industrial, cloud, and consumer markets.

The NST4617MX2T5G belongs to onsemi's general-purpose bipolar transistor product line, engineered specifically for high-gain, low-saturation-voltage amplification in miniaturized surface-mount applications where board space and thermal efficiency are constrained.

FAQ

What is the maximum continuous collector current rating for the NST4617MX2T5G?

The NST4617MX2T5G has a maximum continuous collector current (I_C) rating of 100 mA at T_A = 25°C. This rating assumes proper PCB thermal management-specifically, mounting on a 100 mm², 2 oz. copper pad per datasheet Note 2. Exceeding this current without adequate heatsinking risks thermal runaway and permanent degradation of h_FE and V_CE(sat) in the NST4617MX2T5G.

Does the NST4617MX2T5G support operation at elevated ambient temperatures?

Yes, the NST4617MX2T5G is rated for junction and storage temperatures from −55°C to +150°C. At T_A = 85°C, its usable I_C drops to approximately 55 mA (derated from 100 mA using 5.99 mW/°C slope and 700 mW P_D @ 25°C). The NST4617MX2T5G maintains functional h_FE and V_CE(sat) within specification across this full range when operated within its SOA envelope.

What is the typical transition frequency (f_T) of the NST4617MX2T5G and under what conditions is it measured?

The typical transition frequency (f_T) of the NST4617MX2T5G is 112 MHz, measured at V_CE = 12 V, I_C = 2.0 mA, and f = 30 MHz. This value reflects the frequency at which the small-signal current gain |h_fe| drops to unity and confirms the NST4617MX2T5G's suitability for wideband analog amplification up to ~100 MHz in properly decoupled circuits.

How does the thermal resistance of the NST4617MX2T5G vary with PCB copper area?

The NST4617MX2T5G exhibits two defined thermal resistance values: R_JA = 722 °C/W when mounted on a minimal 0.6 mm², 2 oz. copper pad (Note 1), and R_JA = 167 °C/W when mounted on a 100 mm², 2 oz. copper pad (Note 2). This 4.3× improvement demonstrates the critical impact of PCB layout on thermal performance in the NST4617MX2T5G.

Is the NST4617MX2T5G pin-compatible with other X2DFN3-packaged transistors like the MMBT4401LT1G?

Yes-the NST4617MX2T5G shares identical X2DFN3 (Case 714AC) mechanical dimensions and pinout (Base–Emitter–Collector on pins 1–2–3) with the MMBT4401LT1G. However, electrical characteristics differ significantly: the NST4617MX2T5G offers higher V_(BR)CEO (50 V vs. 40 V) and lower V_CE(sat) (0.08 V vs. 0.12 V), making direct substitution possible only after verifying voltage and gain requirements in the NST4617MX2T5G application.