onsemi NCP134AMX105TCG

Overview

NCP134AMX105TCG from onsemi is a 500 mA very low dropout (VLDO) CMOS voltage regulator with NMOS pass transistor and separate bias rail (VBIAS), delivering 1.05 V output with ±1.5% accuracy over −40°C to +85°C, ultra-low 150 mV dropout at 500 mA, and 80 µA typical bias current-designed for noise-sensitive, space-constrained battery-powered applications such as smartphone core logic rails.

For engineers reviewing the NCP134AMX105TCG datasheet, pinout, applications, or equivalent options, key selection criteria include its dual-rail architecture (VIN/VBIAS), active output discharge capability, XDFN4 1.2 mm × 1.2 mm package, thermal shutdown behavior, and compatibility with 2.2 µF ceramic output capacitors.

Technical Context

The NCP134AMX105TCG employs an NMOS pass transistor architecture powered by independent VIN and VBIAS supplies, enabling ultra-low dropout operation where VIN can approach VOUT closely while internal control circuits remain stable via dedicated bias rail. Its enable input features built-in hysteresis, and the device integrates thermal shutdown (160°C trip, 140°C release) and current limiting (550–1000 mA).

This fixed-output variant includes active output discharge functionality-activated during shutdown to rapidly pull down VOUT-making it suitable for systems requiring controlled power sequencing. The regulator maintains stability with minimal external capacitance (2.2 µF ceramic) and exhibits high PSRR (80 dB from VBIAS, 70 dB from VIN at 1 kHz).

Key Specifications

Pinout & Package

The NCP134AMX105TCG is housed in an XDFN4 1.2 mm × 1.2 mm × 0.4 mm leadless package (Case 711BC), optimized for ultra-dense PCB layouts and thermal performance (R_JA = 170°C/W on 40 mm × 40 mm FR4).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar very low dropout voltage regulator applications.

Compared with the NCP134AMX105TCG, the XC6210B105MR-G offers smaller solution size but sacrifices bias rail noise immunity and active discharge, while the RT9080L-105GJ6F delivers higher current at lower dropout yet lacks the dual-rail architecture essential for ultra-low-noise applications.

Availability

NCP134AMX105TCG is available at Aetrix Electronics and suitable for smartphone processor core rails, tablet GPU I/O supplies, and digital camera ISP core power delivery requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for NCP134AMX105TCG 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, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The NCP134AMX105TCG belongs to onsemi's high-precision, low-noise VLDO family designed specifically for battery-powered portable electronics demanding ultra-small footprint, dual-rail flexibility, and robust transient performance.

FAQ

What is the nominal output voltage of the NCP134AMX105TCG?

The NCP134AMX105TCG is a fixed-output voltage regulator with a nominal output voltage of 1.05 V. This value is laser-trimmed during manufacturing and specified with ±1.5% accuracy over the full operating temperature range (−40°C to +85°C). The "105" in the part number explicitly denotes the 1.05 V output, and no external feedback components are required.

Does the NCP134AMX105TCG support active output discharge?

Yes, the NCP134AMX105TCG includes active output discharge functionality. When the EN pin is driven low, an internal NMOS switch connects the OUT pin to GND, discharging the output capacitor rapidly. This feature is confirmed in the datasheet block diagram (Figure 2) and electrical characteristics table (R_DISCH = 150 Ω typical), and is specific to the "A" suffix variants like NCP134AMX105TCG.

What are the minimum and maximum allowable VBIAS voltages for the NCP134AMX105TCG?

The NCP134AMX105TCG requires VBIAS between 2.4 V and 5.5 V. Per the Electrical Characteristics table, the minimum valid VBIAS is the greater of 2.4 V or (VOUT + 1.40 V), which for 1.05 V output yields 2.45 V minimum. The absolute maximum is 6 V per Absolute Maximum Ratings, but operational upper limit is 5.5 V. Below 2.4 V, the internal UVLO circuit disables regulation.

Can the NCP134AMX105TCG operate with only a single input supply?

No-the NCP134AMX105TCG requires two distinct input supplies: VIN (0.8–5.5 V) for the NMOS pass transistor and VBIAS (2.4–5.5 V) for internal control circuitry. Connecting VIN and VBIAS together is possible only if the combined voltage satisfies both ranges and remains within the VBIAS dropout limit (VBIAS – VOUT ≤ 1.5 V), but this negates the noise-isolation benefit and is not recommended for noise-sensitive applications.

What is the thermal shutdown behavior of the NCP134AMX105TCG?

The NCP134AMX105TCG incorporates thermal shutdown with a trip threshold of 160°C (rising) and hysteresis of 20°C, releasing regulation at 140°C (falling). Once triggered, the output is disabled until junction temperature falls below 140°C, at which point normal operation resumes automatically. This protects against permanent damage during sustained overload or inadequate PCB copper area, and is documented in the Electrical Characteristics table under "Thermal Shutdown Threshold".