Analog Devices Inc./Maxim Integrated MAX6390XS30D4+T

Overview

MAX6390XS30D4+T from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, factory-set 3.00V ±2.5% reset threshold, and dual timeout periods: 1120ms (VCC-initiated) and 140ms (manual reset). It monitors +1.8V to +5.0V supplies while consuming only 3μA at +1.8V, and guarantees valid reset state down to VCC = 1V. It is used in battery-powered controllers requiring reliable power-on reset and user-triggered recovery.

For engineers reviewing the MAX6390XS30D4+T datasheet, MAX6390XS30D4+T pinout, MAX6390XS30D4+T application, or MAX6390XS30D4+T equivalent, key selection criteria include its 3.00V reset threshold accuracy over –40°C to +125°C, 4-pin SC70 package footprint, manual reset input with internal 1.56kΩ pullup, and immunity to negative-going VCC transients up to 150µs at 100mV overdrive.

Technical Context

The MAX6390XS30D4+T implements a precision bandgap-based voltage comparator for VCC monitoring and a dedicated manual reset input with fast 200ns MR-to-RESET delay. Its reset assertion logic combines VCC falling below 3.00V and MR low, with independent timeout timers: one for VCC recovery (1120ms min), another for MR release (140ms min).

Unlike earlier family members, MAX6390XS30D4+T uses a low-value 1.56kΩ internal MR pullup resistor-enabling robust noise immunity in noisy environments without external components-while maintaining guaranteed reset output validity down to VCC = 1V and supporting open-drain operation with external pullup.

Key Specifications

Pinout & Package

MAX6390XS30D4+T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm, suitable for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6390XS30D4+T, MAX6326XR30D4+T omits manual reset entirely-reducing BOM count but eliminating field serviceability-while TPS3808G30DBVR trades integrated MR pullup strength for slightly lower quiescent current, demanding external biasing for reliable button operation.

Availability

MAX6390XS30D4+T is available at Aetrix Electronics and suitable for industrial PLC controllers, battery-powered data loggers, automotive body control modules, and medical wearable sensor hubs requiring stable component supply and long-term lifecycle support.

Supply support for MAX6390XS30D4+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 and mixed-signal ICs for power management, sensing, and interface applications in industrial, automotive, and computing markets.

MAX6390XS30D4+T belongs to the MAX6381–MAX6390 family of ultra-low-power μP supervisors, engineered specifically for reliable reset generation in space- and energy-constrained embedded systems operating across extended temperature ranges.

FAQ

What is the exact reset threshold voltage of MAX6390XS30D4+T and how accurate is it over temperature?

The MAX6390XS30D4+T has a factory-set nominal reset threshold of 3.00V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" with VTH = 2.93V (min), 3.00V (typ), and 3.08V (max) at +25°C, and ±2.5% deviation across temperature. The MAX6390XS30D4+T achieves this using laser-trimmed bandgap references and on-die compensation.

Does MAX6390XS30D4+T support manual reset, and what is the internal pullup value on the MR pin?

Yes, MAX6390XS30D4+T includes an active-low manual reset input (MR) with an internal pullup resistor of 500Ω to 3000Ω (typical 1.56kΩ), as specified in the Electrical Characteristics table under "MR Internal Pullup Resistance". This low-value pullup ensures robust noise rejection and eliminates the need for external biasing-even with long PCB traces or mechanical switches-unlike higher-impedance alternatives such as the MAX6326.

What are the two reset timeout periods supported by MAX6390XS30D4+T, and how are they triggered?

MAX6390XS30D4+T provides two distinct timeout periods: a 1120ms minimum timeout for VCC-initiated resets and a 140ms minimum timeout for manual reset (MR) events. These are explicitly documented in the "Reset Timeout Period MAX6390" section of the datasheet. The VCC timeout begins when VCC rises above the 3.00V threshold; the MR timeout starts when MR transitions from low to high. Both are independent and non-overlapping.

Is MAX6390XS30D4+T compatible with 1.8V systems, and what is its minimum operating voltage?

Yes, MAX6390XS30D4+T operates from +1.0V to +5.5V and is fully functional at 1.8V, where it draws only 3μA typical supply current. Its reset output remains valid and correctly asserted/deasserted down to VCC = 1.0V, as guaranteed in the Absolute Maximum Ratings and Electrical Characteristics tables. This makes MAX6390XS30D4+T suitable for ultra-low-voltage microcontrollers and battery-depleted scenarios.

What package type and footprint does MAX6390XS30D4+T use, and is it RoHS-compliant?

MAX6390XS30D4+T is supplied in a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. The "+T" suffix confirms lead(Pb)-free and RoHS-compliant construction. This compact, surface-mount package supports high-density layouts in portable and wearable electronics, and its thermal resistance (θJA = 322.6°C/W) is characterized per JEDEC JESD51-7 on multilayer boards.