Analog Devices Inc./Maxim Integrated MAX6388XS29D3

Overview

MAX6388XS29D3 from Maxim Integrated is a low-power, dual-voltage microprocessor supervisory circuit with active-high push-pull reset output, factory-set 2.93V VCC reset threshold, and 140ms minimum reset timeout period. It monitors primary supply (VCC) and auxiliary voltage (RESET IN) and guarantees valid reset state down to VCC = 1V. Used in portable battery-powered equipment requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6388XS29D3 datasheet, MAX6388XS29D3 pinout, MAX6388XS29D3 application, or MAX6388XS29D3 equivalent, key selection factors include its dual-monitoring capability, ±2.5% reset threshold accuracy over –40°C to +125°C, 3µA supply current at 1.8V, SC70-4 package footprint, and compatibility with systems needing auxiliary voltage supervision without external comparators.

Technical Context

The MAX6388XS29D3 integrates two independent reset comparators: one for VCC (factory-trimmed to 2.93V nominal) and one for RESET IN referenced to an internal 1.27V bandgap. Reset asserts when either input falls below its respective threshold, and deasserts after a fixed 140ms timeout following recovery.

Its active-high push-pull RESET output drives high during reset assertion and guarantees correct logic state down to VCC = 1V. The device uses BiCMOS process technology, features negative-going VCC transient immunity up to 35µs at 100mV overdrive, and includes no-connection (N.C.) pins for pin-compatible family scalability.

Key Specifications

Pinout & Package

MAX6388XS29D3 is housed in a lead-free 4-pin SC70 package (X4-1), measuring 1.5mm × 1.0mm × 0.8mm, suitable for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6387XS29D3, the MAX6388XS29D3 eliminates external pull-up components and simplifies layout, while TLV809K29DBZR offers lower cost and smaller size but sacrifices dual-supply monitoring - making MAX6388XS29D3 optimal for compact, dual-rail systems demanding minimal BOM and guaranteed reset integrity.

Availability

MAX6388XS29D3 is available at Aetrix Electronics and suitable for portable medical sensors, battery-powered IoT nodes, and industrial handheld terminals requiring stable component supply, long-lifecycle assurance, and lead-free compliance.

Supply support for MAX6388XS29D3 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 industrial, automotive, and computing applications, with emphasis on power management and reliability-critical functions.

The MAX6381–MAX6390 product line delivers ultra-low-power, high-accuracy supervisory circuits for microprocessor reset and power-fail detection in space- and energy-constrained systems.

FAQ

What is the exact reset threshold voltage of MAX6388XS29D3 and how stable is it over temperature?

The MAX6388XS29D3 has a factory-set nominal reset threshold of 2.93V, with guaranteed accuracy of ±2.5% over the full industrial temperature range (–40°C to +125°C). Its 60ppm/°C tempco ensures minimal drift, making it suitable for applications where precise brownout detection is required across wide ambient conditions. This specification is validated per the MAX6381–MAX6390 datasheet revision 4.

Does MAX6388XS29D3 support monitoring of a second voltage, and how is it implemented?

Yes, MAX6388XS29D3 includes a dedicated RESET IN pin that connects to an internal comparator referenced to a stable 1.27V bandgap. To monitor a second voltage, apply the target rail to RESET IN through a resistor divider network - the threshold is set using R1 = R2 × ((V_INTH/1.27V) – 1). This enables flexible dual-supply supervision without adding external comparators or references.

What is the function of the RESET output on MAX6388XS29D3, and what drive capability does it provide?

The RESET output of MAX6388XS29D3 is an active-high push-pull driver. It asserts high during reset conditions (e.g., VCC < 2.93V or RESET IN < 1.27V) and remains high for the full 140ms timeout after recovery. It sources up to 800µA and sinks up to 3.2mA while asserted, eliminating the need for external pull-up resistors and supporting direct connection to most µP reset inputs.

Can MAX6388XS29D3 operate reliably at very low supply voltages, and what is its minimum functional VCC?

Yes, MAX6388XS29D3 guarantees correct RESET output logic state down to VCC = 1.0V, enabling robust operation during deep brownout events. Its supply current remains ultra-low (3µA at 1.8V), and internal circuitry maintains comparator accuracy and timing integrity even as VCC declines - a key advantage over many competing supervisors that fail below 1.5V.

What package type and pin configuration does MAX6388XS29D3 use, and are there alternative packages available?

MAX6388XS29D3 is supplied in a 4-pin SC70 package (X4-1), with pinout: Pin 1 = VCC, Pin 2 = RESET, Pin 3 = RESET IN, Pin 4 = GND. A 6-pin µDFN variant (MAX6388LT29D3) exists with identical electrical specs but different pin mapping and thermal performance - both share the same reset threshold, timeout, and functional behavior.