Analog Devices Inc./Maxim Integrated MAX6740XKSVD3+

Overview

The MAX6740XKSVD3+ 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 reference), 150ms minimum reset timeout, open-drain RESET output, manual reset detect function, and SC70-5 package - used for reliable power-on reset and supply monitoring in multivoltage portable systems.

For engineers reviewing the MAX6740XKSVD3+ datasheet, MAX6740XKSVD3+ pinout, MAX6740XKSVD3+ application, or MAX6740XKSVD3+ equivalent, key selection considerations include its triple-supply monitoring capability, 6µA quiescent current, RSTIN-adjustable threshold down to 0.488V, -40°C to +85°C operation, and compatibility with battery-powered controllers requiring precise sequencing and glitch immunity.

Technical Context

The MAX6740XKSVD3+ integrates three independent voltage monitoring channels: VCC1 (primary I/O supply), VCC2 (secondary core supply), and RSTIN (user-adjustable third supply), each triggering active-low RESET assertion when falling below its respective threshold. Its internal timer guarantees a minimum 150ms reset pulse after all monitored supplies recover.

It features an open-drain RESET output with internal 50kΩ pullup to VCC1 enabling manual reset detect functionality, no external MR pin required - instead, pulling RESET low externally initiates debounced manual reset with 37.5ms debounce and 150ms timeout. The device operates from 1.2V to 5.5V on VCC1 and supports VCC2 down to 0.752V.

Key Specifications

Pinout & Package

MAX6740XKSVD3+ uses a 5-pin SC70-5 package with exposed pad (not electrically connected). Pin 1 is RESET (open-drain active-low output with internal 50kΩ pullup to VCC1), Pin 2 is GND, Pin 3 is VCC2 (secondary supply input), Pin 4 is RSTIN (adjustable threshold input), and Pin 5 is VCC1 (primary supply input).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6743XKSVD3+, the MAX6740XKSVD3+ provides manual reset detect without adding pins, while TPS3808G33DBVR offers lower unit cost but sacrifices triple-monitoring capability and design flexibility.

Availability

MAX6740XKSVD3+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, wearable fitness trackers, and automotive body control modules requiring stable component supply across extended temperature ranges and ultra-low power consumption.

Supply support for MAX6740XKSVD3+ 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 consumer markets.

The MAX6736–MAX6745 family delivers low-power, multi-rail µP supervision in ultra-small packages - engineered specifically for space-constrained, battery-operated systems demanding high accuracy and long-term reliability.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6740XKSVD3+?

The MAX6740XKSVD3+ has a factory-trimmed VCC1 reset threshold of 2.925V, with guaranteed tolerance of ±75mV over the full -40°C to +85°C temperature range. This value is confirmed in Table 1 of the datasheet under suffix "S" for VCC1 and "Y" for VCC2, forming "SY" in the part number. The threshold remains stable with minimal drift versus temperature, supporting reliable reset assertion in varying environmental conditions.

Does the MAX6740XKSVD3+ require an external manual reset button or MR pin connection?

No - the MAX6740XKSVD3+ does not require an external MR pin. Its RESET pin incorporates manual reset detect functionality: pulling RESET low externally (e.g., via pushbutton to GND) initiates a debounced reset with 37.5ms internal debounce and 150ms timeout. The internal 50kΩ pullup to VCC1 eliminates need for external components, simplifying PCB layout and reducing BOM count.

Can the MAX6740XKSVD3+ monitor a 1.2V core supply?

Yes - the MAX6740XKSVD3+ monitors VCC2 with a fixed threshold of 2.188V, but its RSTIN input accepts an external resistor divider referenced to a precise 0.488V internal bandgap. By configuring R1/R2 appropriately, users can set a custom threshold for a 1.2V rail (e.g., trip at 1.15V), enabling accurate supervision of sub-2V core supplies common in modern low-power MCUs and ASICs.

What is the supply current consumption of the MAX6740XKSVD3+ at 1.8V VCC1?

The MAX6740XKSVD3+ draws 5µA minimum and 10µA typical supply current (ICC1) when VCC1 = 1.8V, VCC1 < VCC2, and reset is not asserted - per Electrical Characteristics table, row "VCC1 Supply Current". This ultra-low quiescent current enables multi-year operation from small batteries in always-on edge devices, with negligible impact on system standby power budget.

Is the MAX6740XKSVD3+ pin-compatible with other members of the MAX6736–MAX6745 family?

Yes - all MAX6736–MAX6745 devices use the same 5-pin SC70-5 package and share identical pinout: Pin 1 = RESET, Pin 2 = GND, Pin 3 = VCC2/RSTIN/PFI/POK1 (function varies by part), Pin 4 = RSTIN/MR/VCC2 (function varies), Pin 5 = VCC1. The MAX6740XKSVD3+ uses Pin 3 for VCC2 and Pin 4 for RSTIN, matching the MAX6740/MAX6743 configuration shown in the Pin Configurations diagram.