Analog Devices Inc./Maxim Integrated MAX6388XS46D3

Overview

The MAX6388XS46D3 from Maxim Integrated is a low-power, single-supply microprocessor supervisory circuit with active-high push-pull reset output, factory-set 4.63V reset threshold (±2.5% over -40°C to +125°C), and 140ms minimum reset timeout. It monitors VCC in battery-powered or low-voltage embedded systems and asserts reset during brownout or power-up sequencing.

For engineers reviewing the MAX6388XS46D3 datasheet, MAX6388XS46D3 pinout, MAX6388XS46D3 application, or MAX6388XS46D3 equivalent, key selection criteria include its 4-pin SC70 package, auxiliary RESET IN input for dual-voltage monitoring, guaranteed reset validity down to VCC = 1V, and ±2.5% threshold accuracy across automotive temperature range.

Technical Context

The MAX6388XS46D3 implements a precision bandgap reference and comparator architecture to monitor VCC against a fixed 4.63V threshold while consuming only 3µA at 1.8V. Its internal timer guarantees a minimum 140ms reset assertion after VCC recovers above threshold.

It integrates an auxiliary RESET IN input referenced to a +1.27V internal reference, enabling user-configurable secondary voltage monitoring via external resistor divider. The active-high push-pull RESET output drives high during fault conditions and remains asserted for the full timeout period without requiring external pull-up.

Key Specifications

Pinout & Package

MAX6388XS46D3 is housed in a lead-free 4-pin SC70 package (package code X4-1), measuring 1.3mm × 1.1mm × 0.9mm, optimized for high-density PCB layouts in portable electronics.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6388LT46D3, the MAX6388XS46D3 saves 0.8mm² PCB area in SC70 but has higher thermal resistance; versus TPS3808G33DBVR, it offers dual-rail monitoring and tighter threshold accuracy at the cost of 1.4µA higher ICC.

Availability

MAX6388XS46D3 is available at Aetrix Electronics and suitable for portable medical sensors, automotive body control modules, industrial PLC I/O submodules, and wearables requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6388XS46D3 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 and mixed-signal ICs for demanding industrial, automotive, and computing applications.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy µP supervisory circuits targeting battery-operated and safety-critical embedded systems where reset reliability and minimal footprint are essential.

FAQ

What is the exact reset threshold voltage of the MAX6388XS46D3 and how accurate is it over temperature?

The MAX6388XS46D3 has a factory-set nominal reset threshold of 4.63V, with guaranteed accuracy of ±2.5% over the full operating temperature range of -40°C to +125°C. This specification is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" and applies directly to the MAX6388XS46D3 variant with suffix "46". The threshold is trimmed during production and does not require external calibration.

Does the MAX6388XS46D3 support monitoring of a second voltage rail, and if so, how is it implemented?

Yes, the MAX6388XS46D3 supports dual-voltage monitoring via its dedicated RESET IN pin. This input compares the external voltage to an internal +1.27V reference. By connecting a resistor divider between VCC and GND with the tap at RESET IN, users can set a custom threshold using the formula V_INTH = 1.27V × (R1/R2 + 1). This feature is explicitly documented for MAX6387/MAX6388/MAX6389 in the Pin Description and Detailed Description sections.

What is the function of the RESET output on the MAX6388XS46D3, and what are its drive characteristics?

The RESET output of the MAX6388XS46D3 is an active-high push-pull driver. It asserts high when VCC falls below 4.63V or when RESET IN falls below its derived threshold, and remains high for the full 140ms minimum timeout after recovery. Per the Electrical Characteristics table, VOL is ≤0.3V at ISINK = 80µA (VCC ≥1.0V), and VOH is ≥0.8×VCC at ISOURCE = 150µA (VCC ≥1.8V), confirming robust logic-level compatibility.

Can the MAX6388XS46D3 operate reliably during deep brownout conditions, and down to what VCC level does it guarantee correct reset behavior?

Yes, the MAX6388XS46D3 guarantees correct RESET output logic state down to VCC = 1.0V, as stated in the Absolute Maximum Ratings and Electrical Characteristics tables. This ensures deterministic reset assertion even during severe undervoltage events. The device continues to monitor VCC and assert RESET as long as VCC remains ≥1.0V, and the reset timeout timer functions correctly across this range.

What package type and dimensions does the MAX6388XS46D3 use, and where is the pin 1 indicator located?

The MAX6388XS46D3 uses a lead-free 4-pin SC70 package (package code X4-1), with dimensions of 1.3mm × 1.1mm × 0.9mm. Pin 1 is located at the top-left corner of the top view, identified by a small beveled edge or dot marking adjacent to the pin - consistent with standard SC70 mechanical drawings referenced in the datasheet (document 21-0098). The pinout is VCC (1), RESET (2), RESET IN (3), GND (4).