STMicroelectronics LD1086VY

Overview

LD1086VY from STMicroelectronics is an automotive-grade, fixed-output 5 V low-dropout linear voltage regulator delivering up to 1.5 A output current with ±2% output tolerance across –40 °C to 125 °C, 1.3 V typical dropout at full load, and internal thermal/overcurrent protection. It serves as a primary post-regulator in engine control units, ADAS domain controllers, and infotainment power domains where stable 5 V rail integrity is critical under wide input transients.

For engineers reviewing the LD1086VY datasheet, LD1086VY pinout, LD1086VY application, or LD1086VY equivalent, key selection considerations include its automotive qualification (AEC-Q100 Grade 1), DFN8 (4×4) package thermal performance (R_thJA = 33 °C/W), adjustable/fixed configuration flexibility, and quiescent current flowing into the load-enabling higher efficiency than legacy PNP-based regulators in battery-sensitive systems.

Technical Context

The LD1086VY implements a bandgap-referenced NPN pass transistor architecture with on-chip trimming for ±1% initial output accuracy at 25 °C. Its reference voltage is internally set to 1.25 V, enabling fixed 5 V output via resistor divider feedback in adjustable variants or direct internal connection in fixed versions like LD1086VY.

Thermal regulation is achieved through integrated junction temperature sensing and foldback current limiting, while stability requires only a 10 µF minimum output capacitor-compatible with ceramic or tantalum types. The device maintains regulation down to 3 mA minimum load current and rejects line noise up to 88 dB at 120 Hz with 25 µF output capacitance.

Key Specifications

Pinout & Package

LD1086VY is housed in a thermally enhanced DFN8 (4 mm × 4 mm, 0.75 mm height) package with exposed thermal pad. Pin 1 is marked by a dot; the exposed pad (Pin 9) is electrically connected to GND and must be soldered to a dedicated PCB thermal plane for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed 5 V LDO regulator applications.

Compared with TPS7B8750QKVURQ1 and NCV8775CDT50RKG, LD1086VY offers the best balance of automotive reliability, thermal performance in DFN8, and proven 10 µF stability-making it ideal for cost-sensitive, thermally constrained 1.5 A applications where 1.3 V dropout and ±2% accuracy are design-critical.

Availability

LD1086VY is available at Aetrix Electronics and suitable for engine control units, ADAS camera modules, and infotainment head units requiring stable component supply with AEC-Q100 compliance and long-term automotive lifecycle support.

Supply support for LD1086VY 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The LD1086 series belongs to ST's automotive-qualified linear regulator product line, engineered specifically for robust, high-current post-regulation in harsh-temperature vehicle subsystems where reliability and thermal resilience are non-negotiable.

FAQ

Is LD1086VY pin-compatible with older LD1086 variants in TO-220 or DPAK packages?

Yes-LD1086VY shares identical pin functions (IN, GND, OUT, ADJ/GND) with other LD1086 family members, but its DFN8 (4×4) footprint is physically incompatible with TO-220 or DPAK land patterns. PCB redesign is required for package migration, though schematic connectivity remains unchanged.

What is the minimum recommended output capacitance for stable operation of LD1086VY?

The datasheet specifies a minimum of 10 µF ceramic or tantalum output capacitor for stability. Using X5R/X7R 10 µF/16 V MLCCs placed within 5 mm of the OUT and GND pins ensures phase margin >45° across –40 °C to +125 °C, eliminating need for ESR-tuned capacitors.

Does LD1086VY require an input bypass capacitor, and if so, what value is recommended?

Yes-a 1 µF ceramic capacitor is recommended directly between IN and GND, placed adjacent to the device. This suppresses high-frequency noise from upstream converters and improves transient response; X7R dielectric with 0805 or smaller case size is preferred for low ESL.

Can LD1086VY be used in adjustable-output configurations?

No-LD1086VY is factory-trimmed for fixed 5.0 V output. Adjustable variants (e.g., LD1086D2M, LD1086DTTR) use the ADJ pin with external resistors; LD1086VY ties ADJ internally to GND and does not support external feedback networks.