Analog Devices Inc./Maxim Integrated MAX8511EXK28+

Overview

MAX8511EXK28+ from Maxim Integrated is a 2.8V fixed-output, ultra-low-noise, low-dropout linear regulator delivering up to 120mA output current with 120mV dropout at full load, 40μA ground current, and stable operation with only 1μF ceramic capacitors. It targets noise-sensitive analog and RF power rails in portable battery-powered systems.

For engineers reviewing the MAX8511EXK28+ datasheet, MAX8511EXK28+ pinout, MAX8511EXK28+ application, or MAX8511EXK28+ equivalent, key selection criteria include output noise (230μVRMS), PSRR (72dB @ 1kHz), shutdown current (<1μA), SC70 package footprint, and absence of bypass capacitor requirement.

Technical Context

The MAX8511EXK28+ uses a P-channel MOSFET pass transistor with 1Ω typical R_DS(ON), enabling low dropout and eliminating base-drive current loss. Its architecture omits the BP pin-unlike the MAX8510-so no external bypass capacitor is needed, reducing BOM count and PCB area.

It integrates overcurrent protection (130–300mA limit), thermal shutdown (160°C trip, 10°C hysteresis), and logic-level shutdown control (SHDN active-low, 0.4V max low threshold). The device operates across –40°C to +85°C with input voltage range 2V to 6V and guaranteed 2.8V ±3% output accuracy over load and temperature.

Key Specifications

Pinout & Package

MAX8511EXK28+ is housed in a 5-pin SC70 package (2.0mm × 1.25mm × 0.95mm height) with exposed pad not present. Pin 1 is IN, Pin 2 is GND, Pin 3 is SHDN, Pin 4 is NC (no internal connection), and Pin 5 is OUT. The NC pin must be left unconnected per datasheet guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with the MAX8511EXK28+, the XC6219B282MR-G trades noise and protection for lower quiescent current, while the ADP125ARZ-2.8-R7 delivers superior noise and current headroom at the cost of capacitor size and footprint - making MAX8511EXK28+ optimal for space-constrained, noise-sensitive 120mA applications.

Availability

MAX8511EXK28+ is available at Aetrix Electronics and suitable for wireless audio transceivers, portable medical sensors, industrial handheld scanners, and smart home edge nodes requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.

Supply support for MAX8511EXK28+ 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) designs high-performance analog, mixed-signal, and power management ICs for demanding industrial, communications, and consumer applications.

The MAX8510/MAX8511/MAX8512 family was engineered specifically for ultra-low-noise, low-quiescent-current regulation in space-constrained portable electronics - prioritizing noise, dropout, and capacitor simplicity over raw current capacity.

FAQ

What is the output voltage tolerance of the MAX8511EXK28+ over temperature and load?

The MAX8511EXK28+ guarantees ±3% output voltage accuracy across the full operating temperature range (–40°C to +85°C) and load current (100µA to 80mA). At +25°C with 1mA load, accuracy tightens to ±1%. This tolerance ensures reliable operation of downstream 2.8V logic and analog circuitry without external trimming.

Does the MAX8511EXK28+ require an external bypass capacitor on the BP pin?

No - the MAX8511EXK28+ does not include a BP (bypass) pin and therefore requires no external bypass capacitor. Unlike the MAX8510, its architecture achieves 230μV_RMS output noise without BP capacitance, simplifying design and reducing bill-of-materials count.

What is the minimum input voltage required for the MAX8511EXK28+ to maintain regulation at 120mA load?

At 120mA load and 2.8V nominal output, the MAX8511EXK28+ has a maximum dropout voltage of 135mV. Therefore, the minimum input voltage to sustain regulation is 2.8V + 0.135V = 2.935V. This enables extended runtime from single-cell Li-ion batteries discharging below 3.0V.

Can the MAX8511EXK28+ be used with ceramic output capacitors smaller than 1μF?

No - the MAX8511EXK28+ is specified and tested for stability with a minimum 1μF ceramic output capacitor (X5R or X7R dielectric). Using smaller values risks instability, excessive ringing on load transients, and potential oscillation, especially under varying temperature or load conditions.

How does the shutdown functionality of the MAX8511EXK28+ behave during power-down sequences?

When SHDN is pulled low (≤0.4V), the MAX8511EXK28+ disables its internal reference, error amplifier, and pass transistor, placing the OUT pin in high-impedance state with supply current dropping below 1μA. The exit delay is 300µs typical, ensuring controlled power-up timing for downstream circuitry coordinated by the same microcontroller.