Analog Devices Inc./Maxim Integrated MAX6740XKVRD3

Overview

The MAX6740XKVRD3 from Maxim Integrated is a triple-voltage microprocessor supervisor IC with two factory-trimmed reset thresholds (VTH1 = 2.925V, VTH2 = 2.188V) and one adjustable RSTIN input (488mV threshold), open-drain RESET output, manual reset detect function, and 150ms minimum reset timeout period. It monitors I/O supply (VCC1), core supply (VCC2), and an external voltage via RSTIN in portable, multivoltage embedded systems.

For engineers reviewing the MAX6740XKVRD3 datasheet, MAX6740XKVRD3 pinout, MAX6740XKVRD3 application, or MAX6740XKVRD3 equivalent, this page delivers verified specifications, SC70-5 pin mapping, real-world use cases in battery-powered equipment and power-sequenced controllers, and validated alternative parts for dual/triple-supply monitoring.

Technical Context

The MAX6740XKVRD3 implements a triple-supply supervisory architecture with independent comparators for VCC1, VCC2, and RSTIN, each referenced to precision internal bandgap references. Its reset assertion logic combines ORed fault detection across all three inputs and enforces a fixed 150ms timeout after all supplies recover.

It features an integrated 50kΩ internal pullup on the open-drain RESET pin for manual reset detect functionality, eliminating external components when interfacing with pushbutton switches. The device operates over -40°C to +85°C and draws only 6µA total supply current at 3.3V/2.5V supplies.

Key Specifications

Pinout & Package

MAX6740XKVRD3 is housed in a 5-pin SC70-5 package (2.0mm × 2.1mm, 0.65mm pitch), optimized for high-density portable designs. Pin 1 is RESET (open-drain active-low), Pin 2 is GND, Pin 3 is RSTIN (adjustable threshold input), Pin 4 is VCC2 (secondary supply monitor), and Pin 5 is VCC1 (primary supply monitor).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-supply supervisory applications.

Compared with MAX6740XKVRD3, MAX6743XKVRD3 offers stronger reset drive but loses manual reset convenience, while TPS3808G33DBVR reduces feature count and cost but cannot replace the triple-monitoring capability required in complex multivoltage systems.

Availability

MAX6740XKVRD3 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, handheld barcode scanners, and automotive infotainment subsystems requiring stable component supply with guaranteed long-term sourcing.

Supply support for MAX6740XKVRD3 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 demanding industrial and portable environments.

The MAX6736–MAX6745 family was engineered specifically for space- and power-constrained multivoltage systems requiring reliable triple-supply supervision with minimal external components - exemplified by the MAX6740XKVRD3's integrated RSTIN reference and manual reset detect.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6740XKVRD3?

The MAX6740XKVRD3 has factory-trimmed reset thresholds of 2.925V for VCC1 and 2.188V for VCC2, both with ±2.5% tolerance over -40°C to +85°C. These values correspond to the "SV" suffix in Maxim's ordering nomenclature and are confirmed in Table 1 of the official datasheet. The MAX6740XKVRD3 uses these precise thresholds to supervise standard 3.0V I/O and 2.2V core rails without external calibration.

Does the MAX6740XKVRD3 support manual reset functionality, and how is it implemented?

Yes, the MAX6740XKVRD3 supports manual reset via its open-drain RESET output, which includes an internal 50kΩ pullup resistor to VCC1. When a pushbutton connects RESET to GND, the device detects the low state and asserts RESET for the full 150ms timeout period after release - eliminating need for external pullup or debounce circuitry. This behavior is intrinsic to the MAX6740XKVRD3's design and documented in the Functional Diagram and Pin Description sections.

What is the purpose and electrical specification of the RSTIN pin on the MAX6740XKVRD3?

The RSTIN pin on the MAX6740XKVRD3 provides a third adjustable voltage monitoring input with a precise 0.488V ±1.5% internal reference. It accepts external resistor-divider networks to monitor voltages as low as 0.5V (e.g., battery or auxiliary rails). Input leakage is ≤±10nA, enabling high-resistor dividers that minimize system power draw - a key feature distinguishing the MAX6740XKVRD3 from dual-supply-only supervisors.

What package type and dimensions does the MAX6740XKVRD3 use, and is it RoHS-compliant?

The MAX6740XKVRD3 is supplied in a 5-pin SC70-5 package measuring 2.0mm × 2.1mm with 0.65mm lead pitch. It is available in both leaded and lead-free versions; the "-T" suffix denotes lead-free packaging (replace with "+T" per Maxim's ordering guide). This compact outline supports high-density layouts in portable electronics where board space is at a premium - a defining characteristic of the MAX6740XKVRD3's mechanical implementation.

How does the MAX6740XKVRD3 handle simultaneous faults across multiple supply rails?

The MAX6740XKVRD3 uses OR-logic across its three monitored inputs (VCC1, VCC2, RSTIN): a fault on any rail immediately asserts the open-drain RESET output low. Recovery requires all three supplies to exceed their respective thresholds for the full 150ms timeout period before RESET deasserts - preventing premature release during partial recovery. This deterministic behavior is hard-coded into the MAX6740XKVRD3's comparator and timer architecture.