onsemi NCP189CMTW180TAG

Overview

NCP189CMTW180TAG from onsemi is a 0.5 A adjustable-output LDO regulator with 1.8 V fixed output, ±0.7% initial accuracy at 25°C, 65 mV typical dropout at 500 mA, and integrated Power Good open-collector output. It delivers low noise (10 µV_RMS), high PSRR (85 dB at 1 kHz), and operates from 1.6 V to 5.5 V input - designed for RF power amplifiers and automotive infotainment domain controllers.

For engineers reviewing the NCP189CMTW180TAG datasheet, pinout, applications, or equivalent options, key selection criteria include its WDFNW6 2 mm × 2 mm package, active output discharge, controlled 5 mV/s slew rate, and guaranteed ±1% accuracy over load/temperature for safety-critical power sequencing.

Technical Context

The NCP189CMTW180TAG implements a PMOS pass transistor architecture enabling ultra-low dropout and stable operation with 4.7 µF ceramic capacitors only. Its internal reference is trimmed to 0.6 V, and feedback loop uses the SNS pin (not FB) for fixed-output variants, ensuring precise 1.8 V regulation independent of external resistor tolerances.

Power Good logic incorporates 9 µs blanking on falling edge and 18 µs on rising edge to reject transients, while the EN pin supports 0.4 V low-threshold shutdown with sub-0.1 µA quiescent current. Thermal shutdown activates at 165°C with 15°C hysteresis, and junction-to-board thermal resistance is 6.6°C/W for PCB-level heat dissipation.

Key Specifications

Pinout & Package

Package: WDFNW6 2 mm × 2 mm × 0.75 mm (Case 511DW), 0.65 mm pitch, exposed thermal pad tied to GND for optimal thermal performance (R_JB = 6.6°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A0518PDBVR and MCP1826T-1802E/DB, the NCP189CMTW180TAG provides superior accuracy (±0.7% vs. ±2%), lower dropout (65 mV vs. 110 mV), integrated Power Good for ASIL-B-compliant sequencing, and controlled 5 mV/s slew rate - making it the only option qualified for automotive domain controller core rails requiring functional safety support.

Availability

NCP189CMTW180TAG is available at Aetrix Electronics and suitable for automotive infotainment systems, telematics modules, and RF power amplifier biasing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for NCP189CMTW180TAG 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The NCP189 series is part of onsemi's automotive-grade power management portfolio, engineered specifically for demanding RF and safety-critical systems requiring high PSRR, low noise, and AEC-Q100 qualification support.

FAQ

What is the maximum input voltage rating for the NCP189CMTW180TAG?

The NCP189CMTW180TAG has an absolute maximum input voltage of 6 V, but its recommended operating range is 1.6 V to 5.5 V. Exceeding 5.5 V may trigger internal protection or cause reliability degradation. The device is rated for 6 V only under transient conditions per the Absolute Maximum Ratings table; sustained operation above 5.5 V is not supported. Always verify input rail margins against worst-case battery or DC-DC output variations in automotive designs using the NCP189CMTW180TAG.

Does the NCP189CMTW180TAG require an external resistor divider for 1.8 V output?

No, the NCP189CMTW180TAG is a fixed-output variant with factory-trimmed 1.8 V regulation - it uses the SNS pin internally and does not require external resistors. Unlike the ADJ version (e.g., NCP189CMTWADJTAG), this part connects SNS directly to OUT on the die, eliminating resistor tolerance, temperature drift, and layout sensitivity. The marking "180" in NCP189CMTW180TAG explicitly denotes the 1.8 V fixed option per onsemi's ordering information table.

How does the Power Good (PG) output behave when the NCP189CMTW180TAG is disabled via EN?

When EN is pulled low, the NCP189CMTW180TAG disables the LDO and also disables the internal Power Good circuitry - the PG pin becomes high-impedance (open-drain off). Its logic level is then defined solely by the external pull-up resistor. To ensure PG goes low during disable for proper power sequencing, connect the pull-up resistor to the NCP189CMTW180TAG's own OUT pin. This guarantees PG reflects true output status, even during shutdown, which is essential for automotive reset coordination.

What is the purpose of the active output discharge feature in the NCP189CMTW180TAG?

The active output discharge feature in the NCP189CMTW180TAG provides a 250 Ω (typical) path from OUT to GND when EN is low, rapidly discharging output capacitance. This prevents floating voltages that could cause latch-up or undefined logic states in downstream components during sleep/wake transitions. In automotive applications like telematics modules, it ensures clean, deterministic power-down of 1.8 V I/O rails - critical for meeting ISO 11898-2 bus idle-state requirements and avoiding false CAN wake events caused by residual charge.

Can the NCP189CMTW180TAG be used with output capacitors larger than 4.7 µF?

Yes, the NCP189CMTW180TAG is stable with output capacitors ≥2.2 µF, including values larger than 4.7 µF. However, onsemi cautions that excessively large capacitors (e.g., ≥100 µF) may cause instability under very light load conditions due to phase margin reduction. For best results, use X5R or X7R ceramics with ESR < 10 mΩ. If higher capacitance is needed for hold-up time, parallel a 4.7 µF ceramic with a bulk tantalum or polymer capacitor - but validate stability across temperature and load with the NCP189CMTW180TAG in your specific layout.