onsemi NCP4671DSN10T1G

Overview

NCP4671DSN10T1G from onsemi is a 1.0 V fixed-output, 400 mA dual-rail ultra-low dropout linear regulator featuring CMOS architecture with separate VBIAS and VIN supplies. It delivers ±15 mV output accuracy at 25°C, 180 mV typical dropout at full load, and supports input voltages as low as 1.1 V (VIN ≥ VOUT + 0.1 V). It is designed for power-sensitive applications including portable cameras and battery-powered communication equipment.

For engineers reviewing the NCP4671DSN10T1G datasheet, pinout, applications, or equivalent options, key selection criteria include its dual-rail bias architecture, auto-discharge capability, 0.1 µA standby current, and SOT-23-5 package compatibility with space-constrained PCB layouts.

Technical Context

The NCP4671DSN10T1G implements a dual-rail LDO topology where VBIAS powers internal control circuitry independently from VIN, enabling operation down to 0.9 V input while maintaining stable 1.0 V output. Its internal N-channel pass transistor achieves 180 mV dropout at 400 mA, with bias voltage required between VOUT + 1.6 V and 5.25 V (i.e., 2.6 V to 5.25 V).

It integrates chip enable (CE) with active-high logic, internal pull-down current (1 µA), and an output discharger in the "D" variant-activated during disable to rapidly discharge COUT. PSRR reaches 80 dB at 1 kHz for VIN ripple and 50 dB for VBIAS ripple, supporting noise-sensitive analog and RF subsystems.

Key Specifications

Pinout & Package

Package: SOT-23-5 (Case 1212), Pb-free, 2.7 mm × 2.5 mm × 1.3 mm footprint with exposed thermal pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with MCP1804T-1002E/MB and XC6210B102MR-G, the NCP4671DSN10T1G uniquely combines dual-rail operation, 400 mA capability, and integrated auto-discharge-enabling higher efficiency, smaller solution size, and deterministic power sequencing in space- and battery-constrained portable electronics.

Availability

NCP4671DSN10T1G is available at Aetrix Electronics and suitable for mobile camera modules, wearable health sensors, and IoT edge node microcontrollers requiring stable component supply, RoHS-compliant packaging, and automotive-grade reliability screening.

Supply support for NCP4671DSN10T1G 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 delivering energy-efficient, high-performance silicon solutions for automotive, industrial, cloud, medical, and IoT applications.

The NCP4671 series belongs to onsemi's precision low-dropout regulator product line, engineered specifically for ultra-low-voltage, high-efficiency power management in portable and battery-powered electronics.

FAQ

What is the minimum input voltage required for NCP4671DSN10T1G to regulate 1.0 V output?

The NCP4671DSN10T1G requires VIN ≥ VOUT + 0.1 V = 1.1 V under normal operating conditions (VOUT ≥ 0.8 V). This ultra-low input threshold enables operation directly from partially discharged single-cell batteries. The device also requires VBIAS ≥ 2.6 V (VOUT + 1.6 V) and ≤ 5.25 V to maintain regulation integrity. Below 1.1 V VIN, dropout occurs and output collapses proportionally.

Does NCP4671DSN10T1G include an integrated output discharge transistor?

Yes, the "D" suffix in NCP4671DSN10T1G denotes the auto-discharge variant. When CE is driven low, an internal N-channel transistor actively pulls VOUT to GND, rapidly discharging external output capacitance. This eliminates reliance on external bleed resistors, reduces system wake-up latency, and improves power sequencing control-critical in portable devices with tight timing budgets.

What is the recommended input and output capacitor configuration for NCP4671DSN10T1G?

Per the datasheet, use a 1.0 µF ceramic capacitor (X5R/X7R) placed as close as possible to both VIN–GND and VBIAS–GND. For output, a 2.2 µF or larger ceramic capacitor (X5R/X7R) is required at VOUT–GND. Larger values and lower ESR improve transient response and stability. Avoid high-ESR tantalum capacitors at the output, as they may cause loop oscillation due to insufficient phase margin.

How does the dual-rail architecture of NCP4671DSN10T1G improve performance over conventional LDOs?

The dual-rail architecture isolates the gate drive and reference circuitry (powered by VBIAS) from the main power path (VIN), allowing VIN to drop as low as 1.1 V while maintaining full regulation. Conventional single-rail LDOs require VIN ≥ VOUT + dropout voltage (often >300 mV), limiting usable battery range. This separation also enhances PSRR and enables independent optimization of bias and power rails-improving efficiency and noise immunity in multi-stage power systems.

Can NCP4671DSN10T1G be used with a 3.3 V VBIAS rail while regulating from a 1.2 V VIN source?

Yes-this is a primary use case. With VOUT = 1.0 V, VBIAS must be ≥ 2.6 V and ≤ 5.25 V; 3.3 V falls within that range. VIN can be as low as 1.1 V (e.g., output of a buck converter stepping down from 3.3 V). This configuration decouples control stability from input rail noise, leverages existing system rails efficiently, and maintains 180 mV dropout performance-making NCP4671DSN10T1G ideal for post-regulation after DC/DC conversion stages.