onsemi NCP512SQ18T1

Overview

NCP512SQ18T1 from onsemi is a fixed-output 1.8 V CMOS low-quiescent-current linear voltage regulator in SC-88A (SOT-353) package, delivering up to 80 mA output current with 40 µA typical quiescent current and 180 mV dropout at 80 mA. It integrates PMOS pass transistor, thermal shutdown, current limit, and enable control - designed for battery-powered portable electronics requiring stable low-voltage rail generation.

For engineers reviewing the NCP512SQ18T1 datasheet, pinout, applications, or equivalent options, key selection criteria include ultra-low I_Q, tight output accuracy (±2.0%), industrial temperature range (−40°C to +85°C), SC-88A footprint compatibility, and enable-controlled standby mode for power-sensitive embedded systems.

Technical Context

The NCP512SQ18T1 employs a PMOS pass transistor architecture enabling low dropout and near-zero gate-drive current, eliminating external bias requirements. Its internal error amplifier compares feedback from a precision voltage reference against the regulated 1.8 V output, driving the PMOS gate to maintain regulation under load and line variations.

Enable functionality is implemented as a logic-level input (V_TH(HI) = 1.3 V, V_TH(LO) = 0.3 V) that directly controls internal bias circuits - disabling all active circuitry except ESD protection when pulled low, reducing total current draw to ≤0.1 µA. Thermal shutdown activates at ~160°C junction temperature, latching off until cooldown.

Key Specifications

Pinout & Package

Package: SC-88A (SOT-353), 5-pin surface-mount, 1.9 mm × 1.3 mm × 0.95 mm body, Pb-free, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with NCP512SQ18T1, the MCP1700T-1802E/TT offers lower quiescent current but sacrifices SC-88A footprint and enable control; the XC6206P182MR-G achieves nanoscale I_Q yet lacks enable and has higher dropout - making NCP512SQ18T1 the balanced choice for space-constrained, enable-driven, industrial-temperature portable designs.

Availability

NCP512SQ18T1 is available at Aetrix Electronics and suitable for wearable health monitors, industrial wireless sensor nodes, portable barcode scanners, smart home motion detectors, and battery-powered handheld instruments requiring stable component supply with guaranteed long-term sourcing.

Supply support for NCP512SQ18T1 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, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The NCP512SQ18T1 belongs to onsemi's NCP512 series of ultra-low-I_Q CMOS LDO regulators, engineered specifically for extended-battery-life portable electronics where minimal standby current and small footprint are mandatory design constraints.

FAQ

What is the maximum input voltage rating for the NCP512SQ18T1?

The NCP512SQ18T1 supports an absolute maximum input voltage of 6.0 V. Operation above this level risks permanent damage. For reliable long-term use, the recommended operating input range is 1.8 V to 6.0 V - ensuring proper regulation across the full 1.8 V output while maintaining dropout margin and thermal safety. The NCP512SQ18T1 must never be exposed to input transients exceeding 6.0 V, even momentarily.

Does the NCP512SQ18T1 require an external pull-up resistor on the Enable pin?

No, the NCP512SQ18T1 does not require an external pull-up resistor on the Enable pin. When unused, the Enable pin must be directly connected to Vin to ensure normal operation. The internal circuitry is designed for direct tie-to-rail use - adding a pull-up resistor introduces unnecessary leakage path and potential noise coupling. If system-level control is needed, drive Enable with a clean logic signal referenced to the same ground as the NCP512SQ18T1.

Can the NCP512SQ18T1 operate with a 1.0 µF ceramic output capacitor?

Yes, the NCP512SQ18T1 is fully stable with a 1.0 µF ceramic output capacitor - no minimum ESR requirement applies. This is confirmed in the Applications Information section of the datasheet and validated across temperature and load conditions. Using X5R/X7R 0402 or 0603 MLCCs simplifies layout, reduces cost, and improves reliability versus tantalum alternatives. Larger values (e.g., 2.2 µF) further improve load transient response.

What is the thermal shutdown threshold of the NCP512SQ18T1?

The NCP512SQ18T1 incorporates internal thermal shutdown that activates at approximately 160°C junction temperature. Once triggered, the device disables output and remains off until junction temperature falls below the hysteresis threshold (~140°C). This protection is fully integrated and requires no external components. The NCP512SQ18T1's SC-88A package has R_JA = 400°C/W, so continuous 80 mA operation at 6.0 V input requires careful PCB copper area design to avoid repeated thermal cycling.

Is the NCP512SQ18T1 RoHS-compliant and halogen-free?

Yes, the NCP512SQ18T1 is RoHS-compliant and halogen-free. The "G" suffix variants (e.g., NCP512SQ18T1G) explicitly denote Pb-free and halogen-free construction per JEDEC J-STD-609. Even non-G suffix parts meet RoHS Directive 2011/65/EU requirements. Full material declarations and compliance documentation are available through onsemi's official product page and Aetrix Electronics' quality portal for NCP512SQ18T1.