onsemi NCV8501D50G

Overview

NCV8501D50G from onsemi is a 5.0 V fixed-output, 150 mA micropower LDO linear regulator with integrated active RESET (with programmable delay), ENABLE control, FLAG early-warning monitor, and fault protection including ±15 V reverse battery, +60 V load dump transient tolerance, short-circuit and thermal overload. It delivers ±2.0% output accuracy with 0.6 V dropout at 150 mA and draws only 90 µA quiescent current at 100 µA load - designed for automotive microprocessor power sequencing and battery-backed systems.

For engineers reviewing the NCV8501D50G datasheet, pinout, applications, or equivalent options, this page provides verified technical context, SO-8 pin mapping, real-world use cases in automotive ECUs and telematics modules, and validated alternative parts for supply continuity and design flexibility.

Technical Context

The NCV8501D50G implements a bandgap-referenced error amplifier driving an NPN pass transistor, with independent comparator-based RESET and FLAG circuits referenced to internal 1.28 V bandgap. Its RESET function remains valid down to VOUT = 1.0 V, and the FLAG comparator features 20–100 mV hysteresis with MON pin threshold programmable via external resistor divider.

ENABLE logic includes internal pull-down and ESD-protected input rated for direct battery connection; it activates at ~2.55 V (20 °C) and tolerates up to +11 V with external series limiting. The DELAY pin sources 1.5–3.5 µA to charge an external capacitor, enabling precise reset timing (e.g., 23.8 ms with 33 nF).

Key Specifications

Pinout & Package

NCV8501D50G is housed in an SOIC-8 NB (Case 751-07) Pb-free package, 4.80–5.00 mm × 3.80–4.00 mm × 1.35–1.75 mm, with exposed pad not present (SO-8 variant). Thermal resistance: R_JA = 165 °C/W, R_JC = 45 °C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV73350PDBVR and MAX6715AATA+T, the NCV8501D50G uniquely integrates RESET, FLAG, and DELAY in a single SO-8 package with automotive-grade transient protection - eliminating three discrete components while ensuring deterministic power sequencing in safety-critical vehicle subsystems.

Availability

NCV8501D50G is available at Aetrix Electronics and suitable for automotive body electronics, telematics gateways, and ADAS camera modules requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant sourcing.

Supply support for NCV8501D50G 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, and IoT applications, with leadership in automotive-grade power management and analog solutions.

The NCV8501 series belongs to onsemi's automotive-qualified LDO portfolio, engineered specifically for microprocessor power sequencing in harsh environments - emphasizing robustness against load dump, reverse battery, and wide temperature operation (−40 °C to +150 °C).

FAQ

What is the minimum input voltage required for NCV8501D50G to regulate 5.0 V output at full 150 mA load?

The NCV8501D50G requires VIN ≥ 5.6 V to maintain regulation at 150 mA, based on its maximum 600 mV dropout voltage (VIN − VOUT ≤ 600 mV). At lower input voltages - such as during automotive cold-crank - output will drop out of regulation. The device continues operating down to VIN = −15 V (reverse battery) and withstands +60 V transients without damage, but regulation only occurs above the dropout threshold. Designers should verify worst-case VIN in their application, especially in 12 V systems with cable drop and alternator ripple.

How does the FLAG function work in NCV8501D50G, and how is its threshold set?

The FLAG function in NCV8501D50G is an open-collector comparator output that goes low when the voltage on the MON pin falls below a programmable threshold (typically 1.20 V, with 20–100 mV hysteresis). To configure early warning for 5.0 V output, connect a resistor divider from VOUT to GND with the tap to MON - e.g., 10 kΩ from VOUT to MON and 24.9 kΩ from MON to GND yields ~1.20 V at MON when VOUT = 5.0 V. This allows the MCU to detect impending reset 10–50 ms before RESET asserts, enabling safe state save or communication flush. The NCV8501D50G's FLAG remains functional across the full −40 °C to +150 °C junction range.

Can NCV8501D50G be used in systems without a microcontroller, and what happens to RESET and FLAG if unused?

Yes, NCV8501D50G can operate without a microcontroller: ENABLE can be tied directly to VIN (via optional current-limiting resistor), RESET can be left unconnected or pulled up to VOUT with a 10 kΩ resistor to provide a clean power-good signal to other logic, and FLAG can be tied to VOUT if early warning is not needed. All protection features - reverse battery, load dump, short-circuit, and thermal shutdown - remain fully active regardless of ENABLE/RESET/FLAG usage. The NCV8501D50G defaults to enabled when ENABLE is floating (due to internal pull-down), but intentional connection is recommended for predictable startup behavior in production systems.

What is the purpose of the DELAY pin on NCV8501D50G, and how is the delay time calculated?

The DELAY pin on NCV8501D50G sources a constant current (1.5–3.5 µA, typ. 2.5 µA) to charge an external capacitor, setting the time between VOUT reaching regulation and RESET going high (deasserting). Delay time is calculated as t_DELAY = C_DELAY × (V_DT − V_{RESET_LOW}) / I_CHARGE, where V_DT = 1.4–2.2 V (typ. 1.8 V), V_{RESET_LOW} ≈ 0 V, and I_CHARGE ≈ 2.5 µA. For example, a 33 nF capacitor yields ~23.8 ms delay. This eliminates external RC timers and ensures repeatable reset timing across temperature and voltage - critical for automotive MCU boot sequencing in NCV8501D50G designs.

Is NCV8501D50G pin-compatible with other devices in the NCV8501 family, and what are the package options?

Yes, NCV8501D50G shares identical SOIC-8 NB (Case 751-07) pinout with all fixed-output variants (e.g., NCV8501D25G, NCV8501D33G) and is functionally compatible with adjustable versions (e.g., NCV8501DADJG) - though VADJ pin is NC in fixed-output parts like NCV8501D50G. The SOW-16 exposed-pad variant (e.g., NCV8501PDW50G) has different pin count and layout, so PCB redesign is required for migration. All SO-8 versions use the same footprint, thermal pad (none), and mounting guidelines per onsemi's 751-07 mechanical drawing - enabling drop-in replacement within the fixed-output subfamily without layout changes.