onsemi NCP502SQ31T2G

Overview

NCP502SQ31T2G from onsemi is a fixed-output, low-quiescent-current CMOS linear voltage regulator delivering 3.1 V at up to 80 mA with 40 µA typical quiescent current and ±2.0% output voltage accuracy over −40 °C to +85 °C. It uses a PMOS pass transistor, supports ceramic output capacitors down to 1.0 µF, and features enable control with 1.3 V (turn-on) and 0.3 V (turn-off) thresholds - ideal for battery-powered handheld instruments requiring stable low-power bias.

For engineers reviewing the NCP502SQ31T2G datasheet, pinout, applications, or equivalent options, key selection criteria include dropout voltage at 80 mA (850 mV max), thermal shutdown protection, SC70-5 package compatibility, and enable logic behavior - all critical for space-constrained portable designs with tight power budgets.

Technical Context

The NCP502SQ31T2G implements a PMOS-based LDO architecture with internal voltage reference, error amplifier, and protection circuitry including current limit and thermal shutdown (trip ~160 °C). Its ultra-low 40 µA quiescent current enables multi-week standby in coin-cell–powered devices.

It operates across 1.3 V to 12 V input range, regulates to 3.1 V ±2.0% over temperature and load, and maintains stability with 1.0 µF ceramic output capacitance - eliminating ESR requirements and simplifying layout versus traditional bipolar LDOs.

Key Specifications

Pinout & Package

Package: SC70-5 (Case 419A), 1.25 mm × 1.65 mm × 0.95 mm, Pb-free, surface-mount.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-I_Q LDO applications.

Compared with MCP1700T-3102E/TT and XC6206P312MR-G, the NCP502SQ31T2G uniquely balances ultra-low I_Q, integrated enable, SC70-5 footprint, and guaranteed 80 mA delivery - making it optimal for compact, power-aware systems requiring active power management.

Availability

NCP502SQ31T2G is available at Aetrix Electronics and suitable for portable medical sensors, wireless sensor nodes, handheld test equipment, and smart wearables requiring stable component supply with long-term manufacturability assurance.

Supply support for NCP502SQ31T2G 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 specializing in energy-efficient power management, analog, and sensing technologies for automotive, industrial, and consumer markets.

The NCP502 series belongs to onsemi's low-power linear regulator product line, engineered specifically for battery-operated portable electronics demanding minimal quiescent current and high output accuracy in miniature packages.

FAQ

What is the maximum input voltage rating for the NCP502SQ31T2G?

The NCP502SQ31T2G has an absolute maximum input voltage of 12 V, as specified in the Maximum Ratings table. Operation above this level risks permanent damage. For reliable long-term use, design input rails to stay within 1.3 V to 12 V, with recommended derating for thermal margin - especially at high ambient temperatures or elevated load currents. The NCP502SQ31T2G maintains regulation across this full range when output load and thermal conditions remain within specification limits.

Does the NCP502SQ31T2G require an external output capacitor, and what value is recommended?

Yes, the NCP502SQ31T2G requires an external output capacitor for stability and transient performance. The datasheet specifies a minimum of 1.0 µF ceramic capacitor placed directly at the Vout pin. Larger values (e.g., 2.2 µF–10 µF) improve load transient response and noise suppression. Unlike many older LDOs, the NCP502SQ31T2G imposes no minimum ESR requirement, enabling use of low-ESR X5R/X7R ceramics without risk of oscillation - a key advantage for miniaturized designs.

What is the dropout voltage of the NCP502SQ31T2G at 80 mA output current?

The dropout voltage of the NCP502SQ31T2G is specified as 850 mV maximum at 80 mA output current, measured when Vout drops 3.0% below nominal (i.e., to 3.007 V). This value is guaranteed across the full operating temperature range (−40 °C to +85 °C). At room temperature and light loads, dropout is lower - typically ~600 mV - enabling efficient operation from partially discharged batteries in portable applications where the NCP502SQ31T2G is commonly deployed.

Is the NCP502SQ31T2G pin-compatible with other variants in the NCP502 family?

Yes, all SC70-5 packaged NCP502 variants - including NCP502SQ28T2G, NCP502SQ29T2G, NCP502SQ30T2G, and NCP502SQ31T2G - share identical pinout, package dimensions, and terminal functions. Only the output voltage and top-marking code differ. This allows direct substitution during prototyping or revision changes without PCB modification, provided the system can tolerate the specific output voltage and its associated load regulation and dropout behavior.

What does the 'SQ' suffix indicate in the NCP502SQ31T2G part number?

The 'SQ' suffix in NCP502SQ31T2G denotes the SC70-5 package variant (Case 419A), distinguishing it from the TSOP-5 ('SN') version. This suffix is part of onsemi's standardized ordering nomenclature and confirms the device is supplied in the micro-miniature 5-pin surface-mount package with 0.65 mm lead pitch. The 'T2G' ending indicates tape-and-reel packaging (3000 units per reel) and Pb-free (RoHS-compliant) construction - critical for modern electronics manufacturing compliance.