Analog Devices Inc./Maxim Integrated MAX6740XKYDD3

Overview

The MAX6740XKYDD3 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 primary I/O supply (VCC1), secondary core supply (VCC2), and an external voltage via RSTIN, enabling robust power sequencing and fault detection in multivoltage embedded systems.

For engineers reviewing the MAX6740XKYDD3 datasheet, MAX6740XKYDD3 pinout, MAX6740XKYDD3 application, or MAX6740XKYDD3 equivalent, this device supports precise dual-supply monitoring with user-adjustable third-channel supervision, low 6µA quiescent current, SC70-5 packaging for space-constrained designs, and integrated manual-reset debouncing - critical for portable, battery-powered, and industrial control applications.

Technical Context

The MAX6740XKYDD3 implements a triple-supervisory architecture: VCC1 and VCC2 are monitored against fixed thresholds (2.925V and 2.188V, respectively), while RSTIN accepts externally scaled voltages down to 0.488V via resistor divider. Reset assertion occurs when any monitored input falls below its threshold, and the internal timer enforces a guaranteed 150ms minimum timeout after all inputs recover.

It features an open-drain RESET output with internal 50kΩ pullup to VCC1, enabling manual reset detect functionality - pulling RESET low externally initiates a debounced (37.5–75ms) reset pulse with 150ms hold time. The device operates across -40°C to +85°C and draws only 6µA total supply current at 3.3V/2.5V supplies.

Key Specifications

Pinout & Package

MAX6740XKYDD3 is housed in a 5-pin SC70-5 package (2.0mm × 1.25mm, 0.65mm pitch), optimized for high-density portable and IoT designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6743XKYDD3 and TPS3808G33DBVR, the MAX6740XKYDD3 uniquely combines triple-supply monitoring, adjustable RSTIN input, and integrated manual reset detect in SC70 - offering superior integration for compact, battery-aware systems needing flexible voltage supervision.

Availability

MAX6740XKYDD3 is available at Aetrix Electronics and suitable for portable medical devices, industrial edge controllers, network gateways, and automotive infotainment subsystems requiring stable component supply, long-term lifecycle support, and guaranteed parametric performance across temperature.

Supply support for MAX6740XKYDD3 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, sensing, and connectivity in demanding industrial, medical, and communications applications.

The MAX6736–MAX6745 family was engineered specifically for multivoltage microprocessor systems requiring ultra-low-power, space-efficient supervision with configurable thresholds - targeting portable, battery-operated, and thermally constrained embedded platforms.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6740XKYDD3?

The MAX6740XKYDD3 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 are defined by the "YD" suffix per Maxim's Table 1 and are fully tested and guaranteed - not typical or nominal values. The MAX6740XKYDD3 uses these precise thresholds to supervise common 3.0V I/O and 2.2V core rails without external calibration.

Does the MAX6740XKYDD3 support manual reset, and how is it implemented?

Yes, the MAX6740XKYDD3 supports manual reset via its RESET pin - no dedicated MR pin is needed. Pulling the open-drain RESET output low externally (e.g., with a pushbutton to GND) initiates a debounced reset with 150ms minimum timeout. The MAX6740XKYDD3 includes internal 50kΩ pullup to VCC1 and 37.5–75ms debounce logic, enabling direct button interfacing without external RC networks or logic gates.

Can the MAX6740XKYDD3 monitor a 1.2V supply, and how is that configured?

Yes, the MAX6740XKYDD3 can monitor a 1.2V supply using its RSTIN pin. Since RSTIN triggers at a fixed 0.488V internal reference, a resistor divider (e.g., R1 = 150kΩ, R2 = 100kΩ) scales the 1.2V input to ~0.48V - just below threshold. The MAX6740XKYDD3's <10nA RSTIN input current allows high-value resistors, minimizing power loss. This configuration is validated in Maxim's Figure 3 and supported across full temperature range.

What is the supply current consumption of the MAX6740XKYDD3 under typical operating conditions?

The MAX6740XKYDD3 consumes ≤6µA total supply current when both VCC1 = 3.3V and VCC2 = 2.5V, measured across -40°C to +85°C. This value includes ICC1 (5–10µA) and ICC2 (1–2µA) contributions and is specified in the Electrical Characteristics table (page 2). The MAX6740XKYDD3 achieves this ultra-low IQ via BiCMOS process optimization and dynamic circuit disabling - critical for multi-year battery operation.

Is the MAX6740XKYDD3 pin-compatible with other devices in the MAX6736–MAX6745 family?

No - the MAX6740XKYDD3 uses a unique pinout among the family: Pin 3 = VCC2, Pin 4 = RSTIN, with no MR or PFI/PFO pins. It is not pin-compatible with MAX6736 (MR on Pin 3), MAX6742 (PFI on Pin 3), or MAX6741 (POK1 on Pin 3). Board layout must be designed specifically for the MAX6740XKYDD3's triple-monitoring SC70 configuration - substitution requires PCB revision.