onsemi KA7815E

Overview

KA7815E from ON Semiconductor is a fixed-output +15 V, 1 A positive linear voltage regulator in TO-220 package with thermal overload, short-circuit, and safe operating area protection. It delivers stable output under input voltages from 17.5 V to 30 V and supports industrial temperature range (−40°C to +125°C), commonly used in power supplies for analog instrumentation and embedded control systems.

For engineers reviewing the KA7815E datasheet, pinout, applications, or equivalent options, key selection considerations include dropout voltage (2 V at 1 A), load regulation (≤150 mV over 250–750 mA), ripple rejection (54–70 dB at 120 Hz), output noise (90 μV RMS), and thermal resistance (5°C/W junction-to-case).

Technical Context

The KA7815E implements a classic three-terminal series pass architecture with internal error amplifier, bandgap reference, current-limiting circuitry, and thermal shutdown. Its SOA protection prevents secondary breakdown during transient overloads, while the integrated starting circuit ensures reliable turn-on across the full input range.

It operates as a non-adjustable regulator requiring only two external capacitors (0.33 μF input, 0.1 μF output) for stability. No external feedback network is needed-output voltage is trimmed at wafer level and guaranteed within ±5% (14.25–15.75 V) over load, line, and temperature.

Key Specifications

Pinout & Package

KA7815E is supplied in TO-220 (dual-gauge) package with standard 3-pin configuration: Input (Pin 1), Ground (Pin 2), Output (Pin 3). The metal tab is electrically connected to Pin 2 (GND) and serves as thermal path to heatsink.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output linear regulator applications.

Compared with LM7815CD2T and MC7815BD2TR4, the KA7815E offers the lowest cost and broadest industrial temperature support (−40°C to +125°C), while trading off tighter tolerance and slightly higher dropout for robustness in harsh environments.

Availability

KA7815E is available at Aetrix Electronics and suitable for industrial power supplies, analog sensor interfaces, embedded control boards, and legacy equipment retrofits requiring stable component supply and long-term lifecycle continuity.

Supply support for KA7815E 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 semiconductor supplier specializing in power management, analog, and logic solutions for automotive, industrial, and cloud infrastructure markets.

The KA78XXE series was designed as a drop-in replacement for legacy 78xx regulators, emphasizing ruggedness, wide temperature operation, and integrated protection for industrial and embedded power applications.

FAQ

What is the maximum input voltage for KA7815E?

The KA7815E supports a maximum input voltage of 40 V when configured for 24 V output (per Absolute Maximum Ratings), but for its +15 V variant, the recommended maximum is 30 V under normal operation. Exceeding 30 V risks exceeding safe power dissipation limits and triggering thermal shutdown, especially at high ambient temperatures or without adequate heatsinking.

Does KA7815E require external capacitors?

Yes, KA7815E requires an input capacitor (≥0.33 μF) and output capacitor (≥0.1 μF) for stability and transient response. The datasheet specifies 0.33 μF ceramic at the input and 0.1 μF ceramic at the output in the test circuit. Omitting either can cause oscillation or poor load/line regulation, particularly under dynamic loads.

Is KA7815E pin-compatible with standard 7815 regulators?

Yes, KA7815E uses the industry-standard TO-220 3-pin layout (Input–GND–Output) and matches the pinout, voltage rating, and protection features of legacy 7815 devices including LM7815 and MC7815. It is a direct physical and functional replacement without PCB modification.

What is the thermal shutdown threshold of KA7815E?

The KA7815E activates thermal shutdown at approximately 175°C junction temperature. Once triggered, the output is disabled until the die cools by ~20°C, enabling automatic recovery. This threshold is not user-adjustable and is implemented via internal thermal sensing circuitry integrated into the silicon die.

Can KA7815E be used in adjustable configurations?

While KA7815E is optimized as a fixed +15 V regulator, it can be adapted for adjustable output using external resistive feedback - though this requires careful design to maintain stability and accuracy. The datasheet notes that "these devices can be used with external components for adjustable voltages and currents," but no reference circuit is provided, and performance guarantees (e.g., regulation, noise) no longer apply.