Analog Devices Inc./Maxim Integrated MAX6315US44D2

Overview

MAX6315US44D2 from Maxim Integrated is a low-power CMOS microprocessor supervisory circuit in SOT143 package that monitors VCC supply voltage and asserts an open-drain active-low RESET signal when voltage falls below 4.39V or when manual reset (MR) is asserted. It provides a factory-programmed 20ms minimum reset timeout period, 5µA supply current at +25°C, operates from -40°C to +125°C, and supports level-shifting RESET pull-up voltages up to +6V. It is used in portable battery-powered equipment for reliable power-on reset and brownout protection.

For engineers reviewing the MAX6315US44D2 datasheet, MAX6315US44D2 pinout, MAX6315US44D2 application, or MAX6315US44D2 equivalent, key selection criteria include its precise 4.39V reset threshold, 20ms timeout, SOT143 footprint, open-drain output compatibility with mixed-supply systems, and immunity to short VCC transients.

Technical Context

The MAX6315US44D2 implements a precision voltage-monitoring comparator with laser-trimmed internal resistors to set the 4.39V nominal reset threshold, with ±1.8% tolerance over temperature. Its internal timer generates a guaranteed minimum 20ms reset pulse after VCC rises above threshold or MR deasserts.

It features an integrated 63kΩ pull-up on MR, enabling direct switch-to-ground connection without external components, and its open-drain RESET output uses an n-channel MOSFET capable of sinking 0.5mA at VCC = 3.6V while allowing pull-up to any voltage ≤ +6V - enabling level-shifted reset signaling across supply domains.

Key Specifications

Pinout & Package

SOT143 (4-pin, surface-mount) package with 1.3mm × 1.3mm footprint, 0.95mm height, and gull-wing leads. RoHS-compliant lead-free option available (replace "-T" with "+T").

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX811TEUS46D3-T, the MAX6315US44D2 offers tighter threshold tolerance (±1.8% vs ±2.5%) and lower ICC (5µA vs 12µA), but shorter timeout; versus TPS3808G18DBVR, it provides fixed timing, smaller footprint, and higher V_TH, at the cost of no adjustability.

Availability

MAX6315US44D2 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, smart energy meters, and critical µP power monitoring applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6315US44D2 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, communications, and computing markets, with emphasis on high-reliability, low-power, and small-footprint solutions.

The MAX6315 family delivers highly accurate, low-quiescent-current supervisory circuits for microprocessor reset applications, targeting space-constrained and battery-sensitive systems requiring guaranteed reset timing and robust transient immunity.

FAQ

What is the exact reset threshold voltage of the MAX6315US44D2?

The MAX6315US44D2 has a factory-trimmed nominal reset threshold voltage of 4.39V, with a tolerance of ±1.8% over the full operating temperature range (-40°C to +125°C). This value is laser-trimmed during manufacturing and specified in the Electrical Characteristics table under "Reset Threshold (Note 1)" with VTH = 4.39V, min 4.31V, max 4.47V at TA = -40°C to +125°C.

Does the MAX6315US44D2 support operation with VCC below 2.5V?

No, the MAX6315US44D2 specifies an operating voltage range of +2.5V to +5.5V per its Absolute Maximum Ratings and Electrical Characteristics. Below 2.5V, the internal voltage reference and comparator may not function reliably, and RESET assertion is not guaranteed. The device will not assert valid reset behavior when VCC is less than 2.5V.

Can the RESET output of the MAX6315US44D2 be pulled up to 5V while VCC is at 3.3V?

Yes, the MAX6315US44D2's RESET output is open-drain and rated for voltages up to +6.0V, so it can be safely pulled up to 5V even when VCC = 3.3V. This level-shifting capability allows interfacing with higher-voltage microcontrollers or FPGAs without external translators, as confirmed in the Pin Description and Absolute Maximum Ratings sections.

What is the minimum reset timeout period for the MAX6315US44D2?

The MAX6315US44D2 has a minimum reset timeout period (t_RP) of 20ms, as indicated by the "D2" suffix in its part number and confirmed in the Ordering Information table. This is the guaranteed minimum duration RESET remains asserted after VCC rises above 4.39V or after MR is deasserted, meeting JEDEC JESD78 requirements for microcontroller reset hold time.

Is the MAX6315US44D2 pin-compatible with the MAX811 series?

Yes, the MAX6315US44D2 is explicitly stated as pin-compatible with the MAX811 in the Features section of its datasheet. Both devices use the SOT143 package with identical pin 1 (GND), pin 2 (RESET), pin 3 (MR), and pin 4 (VCC) assignments and electrical behavior, enabling drop-in replacement in existing MAX811-based designs where 4.39V/20ms timing is appropriate.