Analog Devices Inc./Maxim Integrated MAX6381XR16D3+

Overview

MAX6381XR16D3+ from Maxim Integrated is a low-power microprocessor supervisory circuit in 3-pin SC70 package, featuring a factory-set 1.58V reset threshold (suffix '16'), 140ms minimum reset timeout (suffix 'D3'), active-low push-pull reset output, ±2.5% threshold accuracy over -40°C to +125°C, and 3µA supply current at +1.8V. It monitors VCC during power-up/brownout in battery-powered microcontrollers and portable instrumentation.

For engineers reviewing the MAX6381XR16D3+ datasheet, MAX6381XR16D3+ pinout, MAX6381XR16D3+ application, or MAX6381XR16D3+ equivalent, key selection criteria include guaranteed valid reset assertion down to VCC = 1V, negative-going transient immunity, fixed-threshold single-supply monitoring, and compatibility with space-constrained embedded systems requiring stable low-voltage supervision.

Technical Context

The MAX6381XR16D3+ integrates a precision voltage comparator with internal 1.58V reference and a monostable timer for reset assertion. Its reset output remains asserted for ≥140ms after VCC rises above 1.58V, ensuring reliable µP initialization. The device operates across 1.0V–5.5V VCC and guarantees correct logic state down to VCC = 1V.

No manual reset (MR) input or auxiliary RESET IN is present-this variant is optimized for simple single-rail supervision. It uses BiCMOS process (647 transistors) and exhibits 60ppm/°C reset threshold tempco, enabling stable operation in automotive and industrial temperature ranges.

Key Specifications

Pinout & Package

MAX6381XR16D3+ is housed in a 3-pin SC70 package (package code X3-2), with exposed pad not electrically connected. Pin 1 is RESET (active-low push-pull output), Pin 2 is VCC (supply input), and Pin 3 is GND (ground reference).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset applications.

Compared with MAX809TRD3+T and TPS3808G15DBVR, the MAX6381XR16D3+ uniquely delivers 1.58V fixed threshold in the smallest possible package with guaranteed 1V operation-making it optimal for space- and voltage-critical battery-powered designs where threshold precision and minimal BOM are mandatory.

Availability

MAX6381XR16D3+ is available at Aetrix Electronics and suitable for portable medical sensors, battery-powered data loggers, industrial PLC I/O modules, and wearable fitness trackers requiring stable component supply with long-term lifecycle support.

Supply support for MAX6381XR16D3+ 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 high-performance analog, mixed-signal, and power management ICs for industrial, automotive, communications, and computing markets.

The MAX6381–MAX6390 family was designed specifically for low-voltage, low-power microprocessor supervision in space-constrained and battery-sensitive applications, emphasizing precision threshold accuracy, ultra-low ICC, and robust transient immunity.

FAQ

What is the exact reset threshold voltage of MAX6381XR16D3+ and how stable is it over temperature?

The MAX6381XR16D3+ has a factory-set reset threshold of 1.58V, specified with ±2.5% tolerance across the full operating temperature range of -40°C to +125°C. Its temperature coefficient is 60ppm/°C, meaning the threshold drifts less than 10mV over the entire range. This stability is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" and "Reset Threshold Tempco" parameters, making MAX6381XR16D3+ suitable for applications where precise low-voltage detection is critical, such as end-of-battery-life monitoring.

Does MAX6381XR16D3+ include a manual reset input (MR) or auxiliary RESET IN pin?

No, MAX6381XR16D3+ does not include a manual reset input (MR) or auxiliary RESET IN pin. Per the Selector Guide and Pin Description tables, only MAX6384–MAX6386 and MAX6390 feature MR, and only MAX6387–MAX6389 include RESET IN. MAX6381XR16D3+ is a basic single-supply supervisory variant with RESET, VCC, and GND pins only-optimized for simplicity, minimal footprint, and cost-sensitive designs where external reset initiation is unnecessary.

What is the minimum VCC voltage at which MAX6381XR16D3+ guarantees correct reset output logic state?

MAX6381XR16D3+ guarantees valid reset output logic state down to VCC = 1.0V, as explicitly stated in the Absolute Maximum Ratings and Detailed Description sections. Below this voltage, the internal circuitry may not maintain defined behavior-but at and above 1.0V, the active-low push-pull output will correctly assert low during undervoltage and deassert high once VCC exceeds 1.58V and the 140ms timeout expires. This capability is essential for graceful shutdown in deeply brownout conditions.

Can MAX6381XR16D3+ be used with a 1.2V supply rail?

Yes, MAX6381XR16D3+ supports VCC as low as 1.0V and is fully specified down to that level, so it can supervise a 1.2V rail. However, its 1.58V reset threshold means it will assert reset whenever VCC falls below 1.58V-so with a nominal 1.2V rail, reset would be continuously asserted. Therefore, MAX6381XR16D3+ is appropriate only for rails ≥1.58V (e.g., 1.8V, 2.5V, 3.3V). For 1.2V supervision, a different threshold variant (e.g., suffix '12' for 1.20V) or alternate part is required.

What package type and dimensions does MAX6381XR16D3+ use, and is the exposed pad connected?

MAX6381XR16D3+ uses the 3-pin SC70 package (package code X3-2), measuring 1.25mm × 0.85mm × 0.55mm with 0.65mm pin pitch. As shown in the Package Information section and top-mark diagrams, this variant has no exposed thermal pad-only three signal terminals (RESET, VCC, GND). The SC70 outline drawing (21-0075) confirms no thermal pad is present, distinguishing it from µDFN variants that include exposed pads for thermal dissipation.