Analog Devices Inc./Maxim Integrated MAX6740XKVDD3+

Overview

The MAX6740XKVDD3+ 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), 150ms minimum reset timeout, open-drain RESET output, manual reset detect function, and SC70-5 package. It monitors I/O and core supplies in portable multivoltage systems to ensure reliable µP startup and fault recovery.

For engineers reviewing the MAX6740XKVDD3+ datasheet, MAX6740XKVDD3+ pinout, MAX6740XKVDD3+ application, or MAX6740XKVDD3+ equivalent, key selection criteria include its triple-supply monitoring capability, 6µA quiescent current, 150ms reset timeout, RSTIN-adjustable threshold down to 0.488V, and integrated manual reset detect with internal 50kΩ pullup - all in a space-saving 5-pin SC70 package.

Technical Context

The MAX6740XKVDD3+ implements a triple-supply supervisory architecture with independent comparators for VCC1 (2.925V threshold), VCC2 (2.188V threshold), and RSTIN (0.488V reference). Reset assertion occurs when any monitored voltage falls below its threshold, and deassertion requires all three to exceed thresholds for ≥150ms.

It features an open-drain RESET output with internal 50kΩ pullup to VCC1 enabling pushbutton-compatible manual reset detection, no external MR pin, and no POK or PFI/PFO functions - distinguishing it from MAX6741/MAX6742 variants. Operation is guaranteed over -40°C to +85°C with supply range 1.0–5.5V.

Key Specifications

Pinout & Package

Package: SC70-5 (5-pin, single-row surface-mount, 1.6mm × 1.6mm body, 0.9mm height, 0.65mm lead pitch).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6743XKVDD3+, the MAX6740XKVDD3+ provides manual reset detect convenience at the cost of open-drain drive strength; versus TPS3808G33DBVR, it adds critical third-supply monitoring and adjustable threshold flexibility essential for heterogeneous power architectures.

Availability

MAX6740XKVDD3+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, and smart meter power management requiring stable component supply and long-term lifecycle support.

Supply support for MAX6740XKVDD3+ 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, mixed-signal, and power management ICs for demanding industrial, automotive, and computing applications.

The MAX6736–MAX6745 family delivers ultra-low-power, multi-rail supervisory circuits optimized for space-constrained, battery-operated, and multivoltage embedded systems requiring guaranteed reset behavior across temperature and supply variations.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6740XKVDD3+?

The MAX6740XKVDD3+ has a factory-trimmed VCC1 reset threshold of 2.925V, with ±2.5% tolerance over -40°C to +85°C. This value is confirmed by the "SV" suffix in the part number per Table 1 of the datasheet, where "SV" maps to VCC1 = 2.925V and VCC2 = 2.188V. The threshold is internally trimmed and does not require external calibration.

Does the MAX6740XKVDD3+ include a dedicated manual reset (MR) input pin?

No, the MAX6740XKVDD3+ does not have a dedicated MR pin. Instead, it implements manual reset detect on the RESET pin itself: pulling RESET low externally (e.g., via pushbutton to GND) triggers the internal timer, holding RESET low for 150ms after release. This is enabled by the internal 50kΩ pullup to VCC1, eliminating the need for a separate MR pin or external components.

What is the function of the RSTIN pin on the MAX6740XKVDD3+?

The RSTIN pin on the MAX6740XKVDD3+ serves as an adjustable reset input referenced to an internal 0.488V comparator. When used with an external resistor divider, it allows monitoring of a third supply voltage - for example, setting a 1.2V threshold by selecting R1/R2 to scale the input so that 1.2V produces 0.488V at RSTIN. Input bias current is ≤10nA, enabling high-resistance dividers to minimize power loss.

Can the MAX6740XKVDD3+ be used in automotive applications?

Yes, the MAX6740XKVDD3+ is qualified for operation from -40°C to +85°C and features robust transient immunity (35µs glitch rejection at 100mV overdrive), making it suitable for under-hood and cabin automotive applications such as body control modules. Its 6µA supply current and triple-supply monitoring support ASIL-B–level power integrity checks when combined with appropriate system-level diagnostics.

What package type and dimensions does the MAX6740XKVDD3+ use?

The MAX6740XKVDD3+ uses the SC70-5 package: a 5-pin surface-mount package measuring 1.6mm × 1.6mm × 0.9mm with 0.65mm lead pitch. This compact footprint reduces PCB area by over 70% compared to legacy SOIC-8 supervisors and supports fine-pitch reflow assembly, ideal for space-constrained portable and wearable electronics.