Analog Devices Inc./Maxim Integrated MAX4917AEUK/V+T

Overview

MAX4917AEUK/V+T from Maxim Integrated is a 300mA autoretry current-limit switch in 5-pin SOT23 package, featuring 0.2Ω on-resistance, 14ms fault blanking, and reverse current protection. It operates from 2.3V to 5.5V and is designed for SDIO port protection in handheld devices where load fault recovery without host intervention is required.

For engineers reviewing the MAX4917AEUK/V+T datasheet, MAX4917AEUK/V+T pinout, MAX4917AEUK/V+T application, or MAX4917AEUK/V+T equivalent, key selection criteria include guaranteed 300mA forward current limit, autoretry behavior versus latchoff, FLAG fault signaling, and low 0.01μA shutdown current in space-constrained portable designs.

Technical Context

The MAX4917AEUK/V+T integrates forward/reverse current sensing with dual reference comparators, enabling independent detection of overcurrent in both directions. Its internal blanking timer (14ms min) suppresses transient faults during hot-swap events, while the autoretry function cycles ON/OFF with 210–900ms retry time after blanking expires.

It features undervoltage lockout (1.75V–2.25V rising threshold), thermal shutdown at +150°C with 15°C hysteresis, and open-drain FLAG output requiring external pullup to IN. The device remains fully functional across –40°C to +85°C and supports reverse current limiting up to 450mA when VOUT − VIN ≥ 0.5V.

Key Specifications

Pinout & Package

MAX4917AEUK/V+T is housed in a RoHS-compliant 5-pin SOT23 package (2.9mm × 1.6mm × 1.1mm), optimized for high-density portable PCB layouts. The package includes exposed pad for thermal enhancement and is compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-limit switch applications.

Compared with MAX4917AEUK/V+T, the μDFN variant offers superior thermal performance but demands more PCB area, while the TPS22965DSGR trades fault autonomy and bidirectional protection for higher current capacity and simpler control - neither is pin-compatible, and all require distinct layout and firmware integration.

Availability

MAX4917AEUK/V+T is available at Aetrix Electronics and suitable for SDIO port protection, USB peripheral switching, notebook ExpressCard slots, and GPS module power management requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for MAX4917AEUK/V+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, designs precision analog, mixed-signal, and power management ICs for demanding industrial, automotive, and portable applications.

The MAX4917AEUK/V+T belongs to the MAX491x family of intelligent load switches, engineered specifically for fault-resilient power delivery in space-constrained, battery-powered systems with hot-swap requirements.

FAQ

What is the guaranteed forward current limit for MAX4917AEUK/V+T?

The MAX4917AEUK/V+T guarantees a minimum forward current limit of 300mA under all operating conditions across –40°C to +85°C. This value is tested and specified in the Electrical Characteristics table with typical values reaching 450mA, ensuring robust protection against sustained overload while supporting SDIO and USB high-power peripheral loads.

Does MAX4917AEUK/V+T support reverse current limiting, and what is its threshold?

Yes, MAX4917AEUK/V+T provides reverse current limiting with a guaranteed minimum threshold of 450mA when VOUT − VIN ≥ 0.5V. This feature actively shuts off the switch and asserts FLAG if reverse current persists beyond the 14ms blanking period, preventing backfeed from higher-voltage peripherals into the main supply rail.

How does the autoretry function operate in MAX4917AEUK/V+T during an overcurrent fault?

When an overcurrent fault exceeds the 14ms blanking time, MAX4917AEUK/V+T turns OFF and enters autoretry mode, waiting 210–900ms before attempting to re-enable. If the fault persists, it repeats the cycle; if cleared, it remains ON and deasserts FLAG. This eliminates need for host MCU intervention during transient faults.

What is the maximum allowable output capacitance for MAX4917AEUK/V+T?

The maximum safe output capacitance for MAX4917AEUK/V+T is determined by C_OUT < (I_{FWD_MIN} × t_{BLANK_MIN}) / ΔV_IN. With 300mA minimum limit, 14ms blanking, and assuming 100mV allowable input droop, C_OUT must remain below ~42μF. For most SDIO/USB applications, the recommended 0.1μF ceramic capacitor is optimal.

Is MAX4917AEUK/V+T compatible with 1.8V logic-level control signals?

No - MAX4917AEUK/V+T requires ON pin logic-high voltage ≥1.4V (min) for reliable turn-on, and logic-low ≤0.4V for shutdown. While 1.8V GPIO meets the VIH requirement, ensure driver can sink sufficient current during FLAG assertion and that system ground integrity maintains noise margin under dynamic load switching.