Analog Devices Inc./Maxim Integrated MAX4836EUT18C

Overview

MAX4836EUT18C from Maxim Integrated is a 500mA low-dropout linear regulator with integrated current-limiting switch and FLAG output, delivering a fixed 1.8V output from 2.5V–5.5V input. It features 90µA quiescent current, reverse-current protection, thermal shutdown, and programmable soft-start via external capacitor. Used in USB ports and SDIO interfaces where accurate overcurrent detection and latch-off behavior are required.

For engineers reviewing the MAX4836EUT18C datasheet, MAX4836EUT18C pinout, MAX4836EUT18C application, or MAX4836EUT18C equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative parts with documented differences, and supply-chain support for industrial and portable electronics designs.

Technical Context

The MAX4836EUT18C implements a BiCMOS-based LDO architecture with an internal P-channel pass transistor, precision voltage reference (1.23V), and error amplifier. Its FLAG function operates as an open-drain output that asserts low after sustained overcurrent exceeding 540–660mA for >5–17ms (blanking time), latching off the regulator until IN or SHDN is cycled.

Soft-start is controlled by an external capacitor on the SS pin, enabling programmable output ramp time (1ms minimum, up to 150ms with 0.1µF). Reverse-current protection ensures <0.1–2µA leakage when VOUT ≥ VIN, and shutdown reduces quiescent current to 0.1µA while discharging OUT through internal circuitry only in MAX4837 variants.

Key Specifications

Pinout & Package

MAX4836EUT18C is housed in a 6-pin SOT23-6 package (3.0mm × 1.7mm × 1.3mm) with exposed pad internally connected to GND for thermal management. The package meets JEDEC MO-178AB standards and is rated for -40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator with current-limiting applications.

Compared with MAX4836EUT18C, MAX4834EUT18C offers 50% lower current capacity but identical feature set and pinout, while MAX4832EUT18C further reduces current to 100mA - both serve as functional alternatives only when load requirements are strictly bounded below their respective ratings.

Availability

MAX4836EUT18C is available at Aetrix Electronics and suitable for USB ports, SDIO interfaces, notebook I/O rails, and GPS receiver designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MAX4836EUT18C 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 semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and consumer applications.

The MAX4836/MAX4837 family was designed specifically for portable and battery-powered systems needing accurate current-limited 1.8V–3.3V regulation with intelligent fault reporting via FLAG or RESET outputs.

FAQ

What is the output voltage tolerance of the MAX4836EUT18C over temperature?

The MAX4836EUT18C maintains ±2% output voltage accuracy across the full -40°C to +85°C operating range. This specification is guaranteed by design and correlation testing, not just typical characterization. At +25°C, the deviation is tighter - typically within ±1.3%. The 1.8V nominal output remains stable under varying load (1mA–500mA) and line (VIN = VOUT + 1V) conditions, making MAX4836EUT18C suitable for precision 1.8V logic rails where voltage drift could affect timing margins.

Does the MAX4836EUT18C provide reverse-current protection, and how is it implemented?

Yes, the MAX4836EUT18C includes integrated reverse-current protection that limits current flow from OUT to IN to ≤2µA when VOUT ≥ VIN. This is achieved by turning off the internal P-channel pass transistor when VOUT exceeds VIN, preventing backfeeding into upstream supplies. The protection is active across the full operating temperature range and does not require external components. This feature is critical in systems with multiple power domains - for example, when a powered SDIO card could otherwise source current into a disabled host regulator - and is explicitly verified in the Electrical Characteristics table under "Reverse Current at VIN".

How does the FLAG output of the MAX4836EUT18C behave during a short-circuit event?

During a sustained short-circuit at OUT, the MAX4836EUT18C's FLAG output asserts low after the blanking time (5–17ms) and simultaneously latches off the pass transistor, halting output current. Unlike reset-based devices, FLAG remains asserted until IN or SHDN is cycled high-to-low-to-high - no automatic recovery. This behavior prevents repeated fault cycling and gives the system time to diagnose and clear the fault. The latch-off state draws only 0.1µA in shutdown, preserving battery life. This exact sequence is documented in the Detailed Description section and confirmed in typical operating waveforms (toc17–toc21).

What capacitor values are required for stable operation of the MAX4836EUT18C?

The MAX4836EUT18C requires a minimum 3.3µF ceramic output capacitor (COUT) with ESR <0.2Ω for stable operation across -40°C to +85°C and up to 500mA load. A 0.1µF ceramic input capacitor (CIN) between IN and GND is also mandatory for PSRR and transient immunity. For improved noise performance, larger COUT values (e.g., 10µF X7R) are recommended - but capacitance variation with DC bias and temperature must be considered. These values are specified in the Applications Information section and validated in the Typical Operating Characteristics plots (toc06, toc11–toc12), not derived from generic LDO guidelines.

Is the MAX4836EUT18C pin-compatible with other members of the MAX4836/MAX4837 family?

Yes, the MAX4836EUT18C shares identical pinout and package (SOT23-6) with all MAX4836 variants (e.g., MAX4836EUT25C, MAX4836ETT18C) and MAX4837 variants in the same package type. However, it is not pin-compatible with MAX4837 parts because MAX4837 uses RESET (push-pull) on pin 4, whereas MAX4836EUT18C uses FLAG (open-drain) on the same pin. Swapping them without circuit modification will cause incorrect logic-level signaling and potential system malfunction. This distinction is explicitly defined in the Pin Description table and Selector Guide.