onsemi 2SC3117S

Overview

2SC3117S from SANYO is an NPN epitaxial planar silicon transistor designed for high-voltage switching applications, with V_CEO = −160 V, I_C = −1.5 A, P_C = 1 W (T_c = 25°C), f_T = 120 MHz, and h_FE ≥ 100 at I_C = −100 mA - used in color TV sound output stages and DC-DC inverters.

For engineers reviewing the 2SC3117S datasheet, pinout, applications, or equivalent options, key selection criteria include breakdown voltage margin, saturation voltage under load, thermal derating behavior, h_FE grouping consistency, and TO-126 package mechanical compatibility in high-reliability consumer power stages.

Technical Context

This device belongs to a matched complementary pair with 2SA1249 (PNP), sharing identical absolute maximum ratings, package (TO-126), and test conditions. It employs SANYO's MBIT process to achieve high V_CEO and stable h_FE across current range.

Electrical characterization confirms operation up to T_j = 150°C, with V_CE(sat) ≤ −0.5 V at I_C = −1 A / I_B = −100 mA, and Cob = 20 pF at V_CB = −10 V - supporting fast-switching requirements in flyback and line-output circuits.

Key Specifications

Pinout & Package

2SC3117S is housed in a TO-126 plastic package with standard lead configuration: emitter (pin 1), collector (pin 2), base (pin 3). The collector tab is electrically connected to pin 2 and serves as primary thermal path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD127G and 2SC2625, the 2SC3117S offers optimal balance of voltage headroom, current capability, and TO-126 form factor for legacy consumer electronics repair and mid-power switching where thermal constraints prohibit TO-220 use.

Availability

2SC3117S is available at Aetrix Electronics and suitable for color TV repair, analog power supply refurbishment, and industrial relay interface modules requiring stable component supply and long-lifecycle support.

Supply support for 2SC3117S 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

SANYO Electric Co., Ltd. was a Japanese semiconductor manufacturer specializing in analog and power discrete devices before its acquisition by ON Semiconductor in 2011; known for robust TV and audio-grade transistors.

The 2SC3117S belongs to SANYO's ENN1060C series of high-voltage switching transistors, engineered specifically for reliability-critical analog video and power conversion circuits in broadcast and consumer equipment.

FAQ

What is the maximum junction temperature rating for the 2SC3117S?

The 2SC3117S has a maximum junction temperature (T_j) of 150°C, as specified in its Absolute Maximum Ratings table. This rating applies under steady-state conditions with proper heatsinking. Operation beyond this limit risks permanent degradation of h_FE and increased leakage. Derating curves in the datasheet show allowable power dissipation drops linearly above 25°C case temperature - for example, only ~0.5 W is permitted at T_c = 100°C. Always verify thermal design using actual board layout and airflow.

Is the 2SC3117S pin-compatible with the 2SC2625?

Yes, the 2SC3117S and 2SC2625 share identical TO-126 packaging and pinout (Emitter–Collector–Base), making them mechanically interchangeable on PCBs. However, the 2SC3117S delivers higher current (−1.5 A vs. −1.0 A) and tighter h_FE grouping (100–400 vs. 60–120), so substituting 2SC2625 may cause marginal performance in high-load applications. Thermal performance also differs due to internal construction - always revalidate thermal rise and switching waveforms after substitution.

Does the 2SC3117S require a base resistor in switching applications?

Yes, the 2SC3117S requires a series base resistor to limit I_B and prevent damage during turn-on. For reliable saturation at I_C = −1.5 A, a typical design uses I_B ≈ −150 mA (h_FE ≥ 100), implying R_B ≈ (V_drive − V_BE) / 0.15 A. With 5 V TTL drive and V_BE ≈ 1.2 V, R_B ≈ 25 Ω. Lower values improve switching speed but increase driver stress; values below 10 Ω risk excessive base current overshoot. Always include a 100–220 Ω damping resistor in series with the base if driving from high-impedance sources.

Can the 2SC3117S be used in linear amplifier configurations?

The 2SC3117S can operate in linear mode, but it is optimized for switching - not analog amplification. Its h_FE variation across I_C (100–400) and moderate f_T (120 MHz) limit fidelity in wideband audio or RF stages. For linear use, ensure V_CE remains ≥ 2 V to avoid saturation distortion, and strictly observe SOA limits: at V_CE = 10 V, max I_C is ~0.8 A; at V_CE = 50 V, max I_C drops to ~0.25 A. Linear designs should include thermal monitoring, as P_C derates rapidly above 25°C.

What is the typical Cob (output capacitance) of the 2SC3117S and how does it affect switching speed?

The 2SC3117S exhibits Cob = 20 pF at V_CB = −10 V and f = 1 MHz, per its datasheet. This capacitance directly impacts turn-off delay and switching losses in high-frequency applications: higher Cob increases Miller charging time, slowing V_CE rise. In a 20 kHz inverter, Cob contributes ~10% of total switching loss; at 100 kHz, its effect becomes dominant. To mitigate, use low-impedance base drive (≤ 10 Ω) and minimize trace inductance between base resistor and transistor. Avoid paralleling multiple 2SC3117S units without individual gate/base resistors due to Cob mismatch-induced current imbalance.