Analog Devices Inc./Maxim Integrated MAX8840ELT15+T

Overview

MAX8840ELT15+T from Maxim Integrated is a preset 1.5V ultra-low-noise, high-PSRR, low-dropout linear regulator delivering up to 150mA output current with 120mV dropout at 120mA load, 11µV_RMS output noise (100Hz–100kHz), and 78dB PSRR at 1kHz. It employs a p-channel MOSFET pass transistor, achieves 40µA ground current, and operates from 2V to 6V input in battery-powered portable electronics.

For engineers reviewing the MAX8840ELT15+T datasheet, MAX8840ELT15+T pinout, MAX8840ELT15+T application, or MAX8840ELT15+T equivalent, key selection criteria include its 1.5V fixed output, µDFN-6 (1.5mm × 1.0mm) package, BP pin for noise bypass, shutdown current <1µA, and stability with only 1µF ceramic output capacitance.

Technical Context

The MAX8840ELT15+T uses an integrated bandgap reference (1.225V), error amplifier, and p-channel MOSFET pass transistor (typ. 1Ω R_DS(ON)) to regulate output voltage. Its BP pin connects to a 10nF capacitor to shunt high-frequency noise from the internal reference, enabling ultra-low 11µV_RMS noise performance.

Shutdown control is active-low on SHDN; pulling it low disables the reference, error amp, gate driver, and pass transistor, placing OUT in high-impedance state. Thermal protection activates at +160°C with 10°C hysteresis, and current limiting holds output between 150mA (min) and 300mA (max).

Key Specifications

Pinout & Package

MAX8840ELT15+T is housed in a lead-free 6-pin µDFN package measuring 1.5mm × 1.0mm × 0.8mm, with exposed thermal pad (GND-connected) for enhanced power dissipation in space-constrained layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B152MR-G and ADP125ARHZ-1.5-R7, the MAX8840ELT15+T delivers the lowest output noise (11µV_RMS) and highest PSRR (78dB @ 1kHz) in the smallest footprint (1.5mm × 1.0mm), making it optimal for noise-critical, space-limited portable designs where 150mA is sufficient.

Availability

MAX8840ELT15+T is available at Aetrix Electronics and suitable for cellular phone RF modules, portable medical sensors, Bluetooth audio subsystems, and digital camera image processing requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for MAX8840ELT15+T 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

Maxim Integrated (now part of Analog Devices) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX8840 series belongs to Maxim's ultra-low-noise LDO product line, engineered specifically for powering noise-sensitive analog and RF circuitry in battery-operated portable devices where minimal dropout, low quiescent current, and exceptional PSRR are mandatory.

FAQ

What is the output voltage tolerance of the MAX8840ELT15+T over temperature and load?

The MAX8840ELT15+T guarantees ±3% output voltage accuracy across full operating conditions: -40°C to +85°C temperature range and 100µA to 80mA load current. At room temperature and 1mA load, tolerance tightens to ±1%. This specification ensures reliable operation for 1.5V logic interfaces and analog references without external trimming.

Does the MAX8840ELT15+T require an external bypass capacitor on the BP pin, and what value is recommended?

Yes, the MAX8840ELT15+T requires a 10nF ceramic capacitor connected between BP and OUT to achieve its specified 11µV_RMS output noise. Values below 1nF or above 100nF are not recommended, as they degrade noise performance. The BP pin is internally shorted to OUT during shutdown, so the capacitor remains safe and functional in all states.

Can the MAX8840ELT15+T be used with ceramic output capacitors smaller than 1µF?

No - the MAX8840ELT15+T is guaranteed stable only with ≥1µF ceramic output capacitance (X7R or X5R dielectric). Using smaller values risks oscillation or poor transient response. The 1µF minimum applies across all loads and temperatures; derating is unnecessary with proper dielectric selection.

What is the maximum input voltage the MAX8840ELT15+T can withstand continuously?

The MAX8840ELT15+T has an absolute maximum input voltage rating of +7V relative to GND. However, for continuous operation, the recommended input range is 2V to 6V. Exceeding 6V may cause excessive power dissipation or violate thermal limits, especially at high load currents or elevated ambient temperatures.

How does the shutdown function behave on the MAX8840ELT15+T, and what is the exit delay?

Driving SHDN ≤0.4V disables the MAX8840ELT15+T, reducing supply current to <1µA and placing OUT in high-impedance state. When SHDN rises above 1.5V, the regulator exits shutdown with a typical delay of 300µs (to 90% of final output), as measured with R_LOAD = 50Ω. This fast wake-up supports low-latency power sequencing in portable systems.