onsemi NCV78M05BTG

Overview

NCV78M05BTG from onsemi is an automotive-grade 5.0 V, 500 mA fixed-output linear voltage regulator in TO-220 package with internal thermal shutdown, short-circuit current limiting, and safe-area compensation. It operates over −40°C to +125°C junction temperature and delivers stable output under varying line (7–20 V input) and load (5–500 mA) conditions for engine control units, body electronics, and infotainment power rails.

For engineers reviewing the NCV78M05BTG datasheet, pinout, applications, or equivalent options, key selection criteria include its AEC-Q100 qualification, ±2% output accuracy at 25°C, 2.0 V dropout voltage, 62 dB ripple rejection at 120 Hz, and TO-220 thermal performance with heatsink-connected ground pin.

Technical Context

The NCV78M05BTG implements a monolithic series pass transistor architecture with integrated protection circuitry: thermal overload shutdown triggers above +150°C junction temperature, short-circuit current limit holds peak output at 350 mA, and safe-area compensation dynamically reduces short-circuit current as input-to-output differential increases. Its internal bias network draws 3.2 mA typical quiescent current.

Designed for local on-board regulation, it requires no external components for basic operation but benefits from 0.33 µF input bypass capacitance when connected via long traces. Output noise is 40 µV_RMS (10 Hz–100 kHz), and load regulation is 20 mV across 5–200 mA at 25°C.

Key Specifications

Pinout & Package

NCV78M05BTG uses the TO-220 package (Case 221AB), with the metal tab (heatsink surface) internally connected to Pin 2 (Ground). This configuration enables direct mechanical mounting to a heatsink while maintaining electrical grounding.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC78M05BTG, NCV78M05BTG adds AEC-Q100 qualification and tighter output tolerance; versus NCV7805BDTRKG, it offers superior thermal dissipation in TO-220 but occupies more PCB area - making it optimal for thermally demanding under-hood locations.

Availability

NCV78M05BTG is available at Aetrix Electronics and suitable for automotive ECU power supplies, body control modules, and infotainment subsystems requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for NCV78M05BTG 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 supplier focused on energy-efficient electronics for automotive, industrial, cloud, medical, and IoT applications.

The NCV78M00 series is part of onsemi's automotive-qualified linear regulator portfolio, designed specifically for robust, low-noise local regulation in harsh vehicle environments - emphasizing reliability, thermal resilience, and AEC-Q100 compliance.

FAQ

What is the maximum input voltage rating for NCV78M05BTG?

The NCV78M05BTG has an absolute maximum input voltage rating of 35 V DC under normal operating conditions, with a recommended operating range of 7.0 V to 20 V DC. Exceeding 35 V risks permanent damage due to internal breakdown, and operation above 20 V significantly increases power dissipation and thermal stress - requiring careful heatsink sizing per the 5.0°C/W junction-to-case thermal resistance specification.

Does NCV78M05BTG require an input bypass capacitor?

Yes, NCV78M05BTG requires a minimum 0.33 µF input bypass capacitor placed directly across Pins 1 and 2 (Input and Ground) with shortest possible leads. This capacitor stabilizes the regulator under fast load transients and suppresses high-frequency noise from upstream sources. Tantalum, ceramic, or low-ESR polymer capacitors are recommended; omission may cause oscillation or poor line regulation, especially with long input traces.

How does the thermal shutdown feature operate in NCV78M05BTG?

The NCV78M05BTG incorporates a junction temperature sensor that triggers thermal shutdown when die temperature exceeds +150°C. Upon activation, the output is disabled until junction temperature falls below approximately +135°C, enabling automatic recovery. This protection is independent of load current and input voltage - safeguarding the device during sustained overload, inadequate heatsinking, or high ambient temperatures common in automotive engine compartments.

Can NCV78M05BTG be used in parallel to increase output current?

No, NCV78M05BTG is not designed for parallel operation. Its output voltage tolerance (±2%) and load regulation (20 mV) prevent balanced current sharing between multiple units, leading to thermal runaway in the unit with slightly lower output voltage. For higher current needs, use a single higher-current regulator like NCV7805BDTRKG or implement external current boosting with a PNP transistor as documented in Figure 12 of the datasheet - noting that such circuits require additional protection components.

What is the significance of the "NCV" prefix in NCV78M05BTG?

"NCV" denotes an onsemi automotive-grade product variant meeting AEC-Q100 stress test requirements and supporting PPAP documentation. NCV78M05BTG undergoes enhanced process controls, extended temperature validation (−40°C to +125°C), and unique site-specific change management - distinguishing it from commercial-grade MC78M05BTG. The prefix signals suitability for safety-relevant automotive applications where reliability and supply chain traceability are mandatory.