Analog Devices Inc./Maxim Integrated MAX8875EUK36

Overview

MAX8875EUK36 from Maxim Integrated is a 3.6V fixed-output, 150mA low-dropout linear regulator with P-channel MOSFET pass element, 85µA no-load supply current, and active-low open-drain Power-OK (POK) output. It operates from +2.5V to +6.5V input, delivers ±1% output accuracy over temperature, and is optimized for battery-powered portable electronics including cellular phones and modems.

For engineers reviewing the MAX8875EUK36 datasheet, MAX8875EUK36 pinout, MAX8875EUK36 application, or MAX8875EUK36 equivalent, key selection criteria include dropout voltage (110mV at 100mA), reverse-battery protection, thermal shutdown at +170°C, and compatibility with 1µF ceramic output capacitors for stable regulation.

Technical Context

The MAX8875EUK36 integrates a 1.25V bandgap reference, error amplifier, internal resistor divider, and P-channel MOSFET pass transistor (R_DS(ON) ≈ 1.1Ω). Its control loop maintains regulation by comparing feedback against the reference and adjusting gate drive accordingly-without base-drive current, enabling ultra-low quiescent current independent of load.

Power-OK functionality uses an internal comparator monitoring V_OUT against a hysteresis threshold (−5.3% to −13.5% depending on load and V_OUT). POK activates only when V_OUT falls out of regulation due to dropout, current limit, or thermal shutdown-not during SHDN assertion.

Key Specifications

Pinout & Package

MAX8875EUK36 is housed in a 5-pin SOT23-5 package with exposed pad for thermal enhancement. The GND pin serves dual roles: electrical reference and primary heat path-requiring connection to a large copper area or ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX8875EUK36, MAX8885EUK36-T trades reverse-battery protection and lower IQ for higher-ESR capacitor flexibility, while MCP1703T-3602E/MB offers vastly lower quiescent current and higher output current but lacks POK and requires pinout rework-making MAX8875EUK36 optimal for cost-sensitive, battery-powered designs needing integrated fault signaling and robustness.

Availability

MAX8875EUK36 is available at Aetrix Electronics and suitable for cellular telephones, modems, and hand-held instruments requiring stable component supply, long-term lifecycle support, and guaranteed parametric performance across industrial temperature range.

Supply support for MAX8875EUK36 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 precision analog, mixed-signal, and power-management ICs for demanding industrial, communications, and consumer applications.

The MAX8875 product line delivers ultra-low-IQ, small-footprint LDOs with integrated protection features-specifically engineered for extended battery life and reliability in portable wireless equipment.

FAQ

What is the output voltage tolerance of the MAX8875EUK36 over temperature?

The MAX8875EUK36 guarantees ±1% output voltage accuracy over the full operating temperature range of −40°C to +85°C. This specification is production-tested at +25°C and correlated across temperature using Statistical Quality Control methods. At +25°C, typical deviation is within ±0.5%, and the device maintains tight regulation even at 150mA load and minimum input voltage (3.71V), making MAX8875EUK36 suitable for precision analog and digital supply rails.

Does the MAX8875EUK36 require an external pull-up resistor on the POK pin?

Yes, the MAX8875EUK36 POK pin is an open-drain N-channel MOSFET output and must be pulled up externally to generate a valid logic-high level. A 100kΩ resistor connected from POK to the OUT pin is recommended for most applications, minimizing current draw while ensuring fast rise time. Leaving POK unconnected renders the Power-OK function nonfunctional-so proper termination is essential for MAX8875EUK36 to provide reliable power-fail detection in systems requiring supervised startup or brownout recovery.

Can the MAX8875EUK36 operate with a 10µF output capacitor?

Yes, the MAX8875EUK36 is stable with 10µF ceramic or tantalum output capacitors, and doing so improves PSRR, load-transient response, and noise performance. While the minimum stable value is 1µF (for VOUT ≥2.5V), increasing COUT to 10µF reduces output noise spectral density and enhances rejection of high-frequency ripple-particularly beneficial when MAX8875EUK36 follows a switching regulator. However, ensure the capacitor's ESR remains below 0.2Ω to avoid phase-margin degradation.

What happens to the POK output during shutdown of the MAX8875EUK36?

The POK output of the MAX8875EUK36 is disabled during shutdown-meaning it neither asserts nor de-asserts based on output voltage status when SHDN is low. POK only monitors regulation during active operation. When SHDN is pulled low, the internal regulator core powers down, the pass transistor turns off, and POK enters high-impedance state regardless of VOUT level. Therefore, MAX8875EUK36 cannot signal power loss during shutdown; system-level sequencing must account for this behavior when designing power supervision logic.

Is reverse-battery protection active on both IN and SHDN pins of the MAX8875EUK36?

Yes, reverse-battery protection in the MAX8875EUK36 activates when either the IN or SHDN pin falls below GND potential. Internal circuitry detects polarity reversal and disconnects parasitic paths, limiting reverse current to ≤1mA. This dual-pin protection eliminates the need for external series diodes or MOSFETs in handheld devices prone to battery misinsertion-enhancing reliability without adding components. The feature is fully integrated and requires no external configuration, making MAX8875EUK36 especially valuable in cost-sensitive, space-constrained consumer electronics.