onsemi KSD560OTU

Overview

KSD560OTU from ON Semiconductor is an NPN epitaxial silicon Darlington transistor designed for low-speed switching and low-frequency power amplification in industrial applications. It features a 100 V collector-emitter voltage (V_CEO), 5 A DC collector current (I_C), 30 W collector dissipation at T_C = 25°C, and h_FE ranging from 2,000 to 15,000 depending on classification. It is commonly used in relay drivers, motor controls, and solid-state relays.

For engineers reviewing the KSD560OTU datasheet, pinout, applications, or equivalent options, key selection considerations include its TO-220 package thermal performance, Darlington gain structure, saturation voltage behavior at 3 A/3 mA drive, and complementary pairing with KSB601 for push-pull configurations.

Technical Context

The KSD560OTU implements a two-stage NPN Darlington configuration that delivers high DC current gain while maintaining single-package integration. Its internal structure enables base-driven switching with low input current requirements-e.g., 3 mA base current suffices to saturate the device at 3 A collector load-and supports pulsed operation up to 8 A (I_CP) with ≤50% duty cycle.

Thermally, it relies on case-to-ambient conduction via the TO-220 metal tab, rated for 30 W dissipation at T_C = 25°C and derated linearly above 25°C per the published power derating curve. Junction temperature is limited to 150°C, and storage range spans −55°C to +150°C, supporting industrial ambient environments.

Key Specifications

Pinout & Package

Package: TO-220 (3-lead, straight lead form, insulated tab). The metal tab is electrically connected to the collector and must be isolated from chassis ground unless circuit topology requires collector-to-heatsink connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BD679A and TIP122, the KSD560OTU offers superior DC current gain (2K–15K) and lower V_CE(sat), making it preferable for low-base-drive industrial switching where thermal headroom and gain stability are critical-especially when paired with KSB601 in complementary designs.

Availability

KSD560OTU is available at Aetrix Electronics and suitable for relay driver circuits, DC motor control (low-speed), and solid-state relay modules requiring stable component supply and long-term industrial lifecycle support.

Supply support for KSD560OTU 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 is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensors, and logic devices for automotive, industrial, cloud, and consumer markets.

The KSD560OTU belongs to ON Semiconductor's legacy Fairchild discrete transistor portfolio, engineered specifically for robust, high-gain industrial switching and linear amplification where reliability and thermal performance are prioritized over RF or high-speed digital operation.

FAQ

What is the maximum continuous collector current rating for the KSD560OTU?

The KSD560OTU is rated for 5 A DC collector current (I_C) at ambient temperature (T_A = 25°C). This rating assumes proper heatsinking and adherence to the published power derating curve. At elevated case temperatures, allowable current decreases linearly-e.g., ~3.5 A at T_C = 75°C. Always verify thermal design margins using the KSD560OTU's θ_JC and θ_JA values in actual layout conditions.

Is the KSD560OTU pin-compatible with the KSB601?

No-the KSD560OTU (NPN Darlington) and KSB601 (PNP Darlington) have complementary electrical functions but different pinouts: KSD560OTU is Base–Collector–Emitter (1–2–3), while KSB601 uses Emitter–Collector–Base (1–2–3) in TO-220. They are intended for pairing in push-pull or H-bridge topologies, not physical interchange. Always consult both datasheets for layout alignment and thermal isolation requirements when co-mounting.

What is the typical V_CE(sat) of the KSD560OTU under standard operating conditions?

The KSD560OTU exhibits a typical V_CE(sat) of 0.9 V at I_C = 3 A and I_B = 3 mA, with a maximum of 1.5 V under the same conditions. This low saturation voltage minimizes conduction losses and self-heating, especially important in thermally constrained industrial modules. Measured values may vary slightly by h_FE classification (R/O/Y) and junction temperature-designers should use worst-case 1.5 V for thermal calculations involving the KSD560OTU.

Does the KSD560OTU require a base resistor, and how is its value calculated?

Yes-the KSD560OTU requires an external base resistor to limit drive current and ensure reliable saturation. For example, with a 5 V logic driver and target I_B = 3 mA, R_B ≈ (5 V − V_BE(sat)) / 3 mA ≈ (5 − 1.8 V) / 0.003 A ≈ 1.07 kΩ (use 1.0 kΩ standard value). The KSD560OTU's V_BE(sat) ranges from 1.6–2.0 V, so resistor selection must account for worst-case forward drop to guarantee sufficient base current across temperature and unit variance.

Can the KSD560OTU be used in linear amplifier configurations?

Yes-the KSD560OTU is explicitly characterized for low-frequency power amplification per its datasheet designation. Its high h_FE, low distortion in active region, and stable V_BE(sat) make it suitable for Class-A or AB audio output stages, sensor signal boosters, and analog output drivers up to ~100 kHz. Biasing must maintain V_CE > 2 V and keep power dissipation within 30 W (with heatsink) to avoid thermal runaway; always validate quiescent point using the KSD560OTU's published static characteristic curves.