onsemi KSH117ITU

Overview

KSH117ITU from ON Semiconductor is a PNP silicon Darlington transistor in D-PAK surface-mount package, rated for -100 V V_CEO, -2 A DC collector current, and 20 W collector dissipation at T_C = 25°C, with minimum h_FE of 500 at I_C = -0.5 A - used in high-gain linear and switching power control circuits such as relay drivers and motor controls.

For engineers reviewing the KSH117ITU datasheet, pinout, applications, or equivalent options, key selection criteria include its built-in emitter-collector damper diode, -4 V V_BE(sat) at -4 A/-40 mA drive, -3 V V_CE(sat) under pulse conditions, and SOA-limited operation up to 150°C junction temperature.

Technical Context

The KSH117ITU implements a monolithic PNP Darlington pair with integrated damper diode across collector-emitter, enabling snubberless inductive load switching. Its high h_FE (up to 12,000) reduces required base drive current while maintaining V_CE(sat) ≤ -3 V at full-rated pulse current.

Thermal design relies on case-mounted heatsinking due to 20 W P_C rating at T_C = 25°C and steep derating curve (zero dissipation at ~155°C). The device operates with V_EB(on) = -2.8 V at -2 A, confirming robust turn-on behavior under heavy load.

Key Specifications

Pinout & Package

D-PAK (TO-252) surface-mount package with exposed drain pad thermally connected to collector; 3-terminal configuration optimized for automated assembly and thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP Darlington transistor applications.

Compared with KSH117ITU, MJD117G offers improved saturation performance but lacks the integrated damper diode, increasing design complexity; TIP117 provides higher power handling in through-hole format but sacrifices SMT automation and thermal interface efficiency.

Availability

KSH117ITU is available at Aetrix Electronics and suitable for relay drivers, DC motor controllers, solenoid interfaces, and linear regulator pass elements requiring stable component supply and long-term industrial availability.

Supply support for KSH117ITU 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

ON Semiconductor (formerly Fairchild Semiconductor) is a global leader in intelligent power and sensing solutions, serving automotive, industrial, cloud, and consumer markets with energy-efficient semiconductor technologies.

The KSH117ITU belongs to ON Semiconductor's legacy power bipolar transistor family, designed specifically for high-reliability, medium-power linear and switching applications in industrial control and power management systems.

FAQ

What is the maximum continuous collector current rating for KSH117ITU?

The KSH117ITU has a maximum DC collector current rating of -2 A at T_C = 25°C. This rating assumes adequate heatsinking; actual usable current decreases with rising case temperature per the derating curve in the datasheet. For reliable operation above 25°C, thermal design must ensure T_C remains within specification. The KSH117ITU also supports -4 A pulsed current under specified test conditions (PW ≤ 300 µs, duty cycle ≤ 2%).

Does KSH117ITU include an integrated damper diode, and how is it connected?

Yes, the KSH117ITU integrates a damper diode between emitter and collector, with cathode connected to collector and anode to emitter. This configuration clamps inductive flyback voltage during turn-off, protecting the transistor in relay and solenoid applications. The diode is monolithically fabricated and electrically verified per datasheet test conditions - no external diode is required when using KSH117ITU in standard inductive load switching.

What package type is used for KSH117ITU, and what are its thermal characteristics?

The KSH117ITU uses the D-PAK (TO-252) surface-mount package with an exposed collector pad. Its thermal resistance from junction-to-case (R_θJC) is not explicitly listed, but the 20 W P_C rating at T_C = 25°C implies R_θJC ≈ 1.25°C/W. Effective thermal performance requires soldering the collector pad to ≥1 in² of 2-oz copper with thermal vias. The KSH117ITU junction temperature must not exceed 150°C under any operating condition.

How does the DC current gain (h_FE) of KSH117ITU vary with operating conditions?

The KSH117ITU specifies h_FE min = 500 at V_CE = -3 V and I_C = -0.5 A, rising to 1000 at I_C = -2 A, and dropping to 200 at I_C = -4 A. Gain is highly dependent on collector current and V_CE; typical curves show peak h_FE near -1 A. Designers must verify h_FE at their specific operating point - the KSH117ITU's gain variation directly impacts base drive requirements and stability margins in linear applications.

Is KSH117ITU a direct replacement for TIP117 in existing designs?

No, KSH117ITU is not a direct replacement for TIP117 due to differing packages (D-PAK vs. TO-220) and pinouts. While both share identical electrical specifications including V_CEO, I_C, and h_FE, the KSH117ITU requires PCB redesign for surface-mount assembly and thermal pad layout. However, the KSH117ITU can replace TIP117 in new designs targeting automated manufacturing, smaller footprint, and improved thermal interface - provided the damper diode integration and SMT process are accounted for.