onsemi NCP511SN27T1G

Overview

NCP511SN27T1G from onsemi is a fixed-output, low-dropout linear voltage regulator delivering 2.7 V at up to 150 mA, featuring 40 µA typical quiescent current, 100 mV dropout at 100 mA, and ±2.0% output voltage accuracy over −40°C to +85°C - designed for battery-powered portable instrumentation requiring stable low-power bias.

For engineers reviewing the NCP511SN27T1G datasheet, pinout, applications, or equivalent options, key selection criteria include ultra-low IQ, TSOP-5 footprint compatibility, enable-controlled standby, ceramic capacitor stability, and automotive-grade NCV-series variants.

Technical Context

The NCP511SN27T1G integrates a PMOS pass transistor with internal voltage reference, error amplifier, thermal shutdown, and current-limit protection - enabling stable regulation without external compensation. Its enable input provides logic-level control (V_TH(HI) = 1.3 V, V_TH(LO) = 0.3 V) for system power sequencing.

Designed for operation from 2.7 V output up to 6.0 V input, it maintains regulation down to 100 mV headroom at 100 mA load and achieves 50 dB ripple rejection at 1 kHz. Ground pin current remains ≤40 µA at no load and scales linearly with output current.

Key Specifications

Pinout & Package

The NCP511SN27T1G is housed in a Pb-free TSOP-5 surface-mount package (3.00 × 1.50 × 0.95 mm, 0.95 mm pitch), optimized for space-constrained portable PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2702E/TT and TPS7A0527PDBVR, the NCP511SN27T1G offers the lowest dropout (100 mV) among the three at 100 mA, retains an enable function in TSOP-5, and delivers optimal trade-off between IQ, thermal performance, and ease of layout for mid-current portable systems.

Availability

NCP511SN27T1G is available at Aetrix Electronics and suitable for portable medical sensors, industrial data loggers, wearable fitness trackers, and smart meter subsystems requiring stable component supply with guaranteed long-term sourcing.

Supply support for NCP511SN27T1G 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, delivering silicon solutions for automotive, industrial, cloud, and IoT applications.

The NCP511 series belongs to onsemi's precision analog LDO portfolio, engineered specifically for ultra-low-power battery-operated devices where extended runtime and small-footprint integration are critical design constraints.

FAQ

What is the maximum input voltage rating for the NCP511SN27T1G?

The NCP511SN27T1G has an absolute maximum input voltage of 6.0 V. Exceeding this rating risks permanent damage. For inputs above 6.0 V, a pre-regulator stage (e.g., resistive divider + Zener or upstream buck converter) is required per Figure 22 in the datasheet. Operation at 6.0 V is permitted only with adequate thermal management due to power dissipation limits.

Does the NCP511SN27T1G require an external output capacitor, and what value is recommended?

Yes, the NCP511SN27T1G requires a minimum 1.0 µF ceramic output capacitor placed close to the Vout and GND pins. The device is stable across ESR values from near-zero up to 3.0 Ω, allowing use of low-ESR MLCCs without phase-margin risk. Larger values (e.g., 10 µF) improve load transient response and noise filtering but are not mandatory for basic regulation.

How does the Enable pin function on the NCP511SN27T1G, and what happens when it's left unconnected?

The Enable pin on the NCP511SN27T1G is an active-high control: pulling it ≥1.3 V turns the regulator on; pulling it ≤0.3 V disables output and reduces quiescent current to <0.1 µA. If unused, the pin must be tied directly to Vin - floating the pin may cause erratic startup or oscillation due to noise susceptibility, as confirmed in the Pin Function Description section.

Is the NCP511SN27T1G suitable for automotive applications?

The NCP511SN27T1G is not qualified for automotive use. However, its pin-compatible variant NCV511SN27T1G is AEC-Q100 qualified and PPAP capable, with identical electrical specs and enhanced process controls for automotive environments. For automotive designs, NCV511SN27T1G must be specified instead of NCP511SN27T1G.

What thermal considerations apply when operating the NCP511SN27T1G at full 150 mA load?

At 150 mA and 6.0 V input (3.3 V drop), the NCP511SN27T1G dissipates ~495 mW. With R_JA = 250°C/W, junction temperature rise exceeds safe limits without PCB thermal relief. Designers must use generous copper pour on Vin/GND/Vout pads, multiple thermal vias, and avoid enclosing the TSOP-5 package - derating to ≤100 mA is recommended for ambient >60°C unless thermal design is verified.