Analog Devices Inc./Maxim Integrated MAX6874ETJ+

Overview

The MAX6874ETJ+ from Maxim Integrated is an EEPROM-configurable, multi-voltage power-supply sequencer/supervisor with six voltage monitor inputs (IN1–IN6), four general-purpose logic inputs (GPI1–GPI4), and eight programmable open-drain outputs (PO1–PO8). It supports configurable undervoltage detection thresholds from +0.5V to +13.2V in fine increments (10–50mV), 25µs–1600ms programmable output timing delays, ±1% threshold accuracy, and operates across –40°C to +85°C in a 32-pin thin QFN package. It is used in telecom central office systems and multimicroprocessor server power sequencing.

For engineers reviewing the MAX6874ETJ+ datasheet, MAX6874ETJ+ pinout, MAX6874ETJ+ application, or MAX6874ETJ+ equivalent, key selection criteria include its dual-range high-voltage input (IN1), I²C/SMBus configuration interface, internal 4kb user EEPROM, watchdog timer configurability, and support for margining disable and manual reset controls in high-reliability power management designs.

Technical Context

The MAX6874ETJ+ implements a virtual diode-OR power selection architecture, deriving internal supply from either IN1 (≥+6.5V) or the highest of IN3–IN5 (≥+2.7V), with ABP regulated at +5.4V and DBP at +2.55V. Its analog block includes six independent voltage comparators with programmable hysteresis and a 1.25V reference, while the digital block integrates an SMBus/I²C controller, configuration register bank, and timing logic for eight output stages.

Each of the eight open-drain outputs is independently configurable for active-high/active-low assertion, conditional triggering (on IN_, GPI_, MR, MARGIN, WD, or other PO_), and timeout delay selection from eight discrete values (25µs to 1600ms). Two watchdog timers support independently programmable initial and normal timeout periods (6.25ms to 102.4s), with clear conditions defined by GPI_/PO_ combinations.

Key Specifications

Pinout & Package

MAX6874ETJ+ is housed in a 32-pin thin QFN (7mm × 7mm × 0.8mm, pkg code T3277-2) with exposed paddle (EP) internally connected to GND. The package supports reflow soldering per JEDEC J-STD-020 and provides low thermal resistance for reliable operation in thermally constrained systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power-supply sequencing applications.

Compared with MAX6875ETJ+, the MAX6874ETJ+ provides two additional voltage inputs and three extra programmable outputs for complex multi-rail systems, while compared with TPS659122ZQV, it delivers higher voltage monitoring capability, field-programmable sequencing logic, and nonvolatile user storage - making it optimal for high-reliability, upgradeable power management in infrastructure equipment.

Availability

MAX6874ETJ+ is available at Aetrix Electronics and suitable for telecommunications central office systems, server/workstation power sequencing, and base station RF module control requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX6874ETJ+ 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 precision analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The MAX6874ETJ+ belongs to Maxim's EEPROM-programmable power-supply sequencer/supervisor product line, designed specifically for high-accuracy, field-configurable power sequencing in telecom infrastructure, enterprise servers, and multimicroprocessor systems where flexibility and reliability are critical.

FAQ

What is the maximum input voltage supported by the MAX6874ETJ+ high-voltage detector IN1?

The MAX6874ETJ+ IN1 input supports a maximum voltage of +13.2V in the 50mV threshold increment range, and +7.625V in the 25mV increment range. Absolute maximum rating for IN1 is +14V. Operation above +13.2V violates the specified functional range, even if within absolute limits. The MAX6874ETJ+ must be powered via IN1 ≥+6.5V or IN3–IN5 ≥+2.7V to ensure full functionality.

How does the MAX6874ETJ+ select its internal power source between IN1 and IN3–IN5?

The MAX6874ETJ+ uses a virtual diode-ORing scheme: it draws power from IN1 if VIN1 ≥+6.5V, otherwise from the highest voltage among IN3–IN5 (provided ≥+2.7V). If +4V < VIN1 < +6.5V and any IN3–IN5 > +2.7V, the power source is indeterminate due to LDO dropout. The internal ABP supply equals +5.4V when powered by IN1, or the max of IN3–IN5 when powered by them. This behavior is intrinsic to the MAX6874ETJ+ architecture.

Can the MAX6874ETJ+ outputs drive standard CMOS logic directly?

No - all eight outputs (PO1–PO8) of the MAX6874ETJ+ are open-drain and require external pull-up resistors to a valid logic supply (e.g., +3.3V or +5V). They do not provide active pull-up. The VOL specification is 0.3V at 500µA (PO1–PO4) or 1mA (PO5–PO8), confirming compatibility with standard CMOS input thresholds when properly pulled up. Driving CMOS loads directly without pull-ups will result in undefined logic levels.

What is the purpose of the MARGIN pin on the MAX6874ETJ+ and how does it interact with MR?

The MARGIN pin on the MAX6874ETJ+ holds all programmable outputs in their current state when driven low, overriding manual reset (MR) if both are asserted simultaneously. It is internally pulled up to DBP via a 10µA current source. During production testing, MARGIN enables voltage margining by freezing sequencing states while rail voltages are adjusted. Unlike MR, which triggers output assertion, MARGIN is a hold function - a key distinction in the MAX6874ETJ+ control architecture.

Does the MAX6874ETJ+ support hot-swap or in-circuit reprogramming of its configuration EEPROM?

Yes - the MAX6874ETJ+ supports full in-circuit reprogramming of both configuration EEPROM and 4kb user EEPROM via its I²C/SMBus interface while powered and operating. Configuration locks (write-disable and config-lock bits) can be set to prevent accidental writes, but remain reprogrammable when unlocked. No power cycle or external programmer is needed; all updates occur dynamically through the serial interface, a core capability of the MAX6874ETJ+ design.