Analog Devices Inc./Maxim Integrated MAX6327UR26

Overview

MAX6327UR26 from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit designed to monitor 2.63V power supplies in embedded digital systems. It asserts a high-level reset signal when VCC falls below 2.63V and holds it for ≥100ms after VCC recovers, with ultra-low 1µA max supply current and guaranteed operation down to VCC = 1V. Used in portable battery-powered controllers and automotive ECUs requiring reliable brownout detection.

For engineers reviewing the MAX6327UR26 datasheet, MAX6327UR26 pinout, MAX6327UR26 application, or MAX6327UR26 equivalent, this device delivers precision 2.63V threshold supervision with factory-trimmed accuracy (±1.5% at +25°C, ±2.5% over –40°C to +85°C), transient-immune reset timing, and SOT23-3 compatibility with legacy MAX809/MAX810 designs.

Technical Context

The MAX6327UR26 implements a precision bandgap-based voltage comparator with hysteresis (9.5mV typical) to reject fast VCC transients while maintaining stable reset assertion during brownout. Its internal reset timer guarantees ≥100ms minimum timeout after VCC exceeds the 2.63V threshold, independent of supply ramp rate.

As a member of the MAX6326–MAX6328 family, it shares identical SC70/SOT23-3 packaging, 1µA max ICC, and –40°C to +85°C operating range, differing only in reset polarity (active-high push-pull) and factory-set threshold (2.63V). All variants are specified for VCC down to 1V and include power-supply glitch immunity per Typical Operating Characteristics data.

Key Specifications

Pinout & Package

MAX6327UR26 is housed in a 3-pin SOT23-3 package (JEDEC MO-178AA), with 1.3mm × 2.9mm footprint and 0.95mm height. Pin 1 = VCC, Pin 2 = RESET (active-high push-pull), Pin 3 = GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TR26D3T and TPS3808G12DBVR, the MAX6327UR26 offers the lowest guaranteed supply current (1µA max), native active-high push-pull drive eliminating external components, and exact SOT23-3 pinout compatibility with legacy Maxim supervisors-enabling seamless drop-in replacement in cost-sensitive, battery-constrained designs.

Availability

MAX6327UR26 is available at Aetrix Electronics and suitable for portable medical monitors, automotive body control modules, industrial PLC I/O expanders, smart energy meters, and critical microcontroller applications requiring stable component supply and long-term lifecycle support.

Supply support for MAX6327UR26 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 U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, communications, and computing markets.

The MAX6326–MAX6328 family was designed specifically for ultra-low-power microprocessor supervision in battery-operated and space-constrained systems, emphasizing precision threshold accuracy, minimal supply current, and robust transient immunity without external components.

FAQ

What is the exact reset threshold voltage of MAX6327UR26 and how tightly is it specified?

The MAX6327UR26 has a factory-trimmed nominal reset threshold of 2.63V. At +25°C, this is guaranteed within ±1.5%; over the full operating temperature range of –40°C to +85°C, the tolerance widens to ±2.5%. This specification is confirmed in the Electrical Characteristics table of the official datasheet and applies directly to the MAX6327UR26 variant, not the broader family.

Does MAX6327UR26 provide active-high or active-low reset output, and what is its drive capability?

The MAX6327UR26 provides an active-high push-pull reset output. When reset is asserted (i.e., VCC < 2.63V), the RESET pin drives logic high; when inactive, it drives logic low. It sources up to 800µA (VOH ≥ 0.8·VCC) and sinks up to 3.2mA (VOL ≤ 0.4V), enabling direct connection to most µP reset inputs without external components. This is explicitly defined in the Pin Description and Electrical Characteristics sections for MAX6327/MAX6347 devices.

What is the minimum VCC voltage at which MAX6327UR26 remains functional and asserts valid reset?

The MAX6327UR26 is guaranteed to maintain correct reset state functionality down to VCC = 1.0V. Below this voltage, the device may not reliably assert or deassert reset. This specification is stated in the General Description and Absolute Maximum Ratings sections and applies across the full –40°C to +85°C temperature range, ensuring robust operation during deep brownout conditions.

How does MAX6327UR26 handle fast voltage transients on the VCC line?

The MAX6327UR26 incorporates built-in power-supply transient immunity: its reset comparator ignores negative-going VCC glitches shorter than ~200µs (depending on overdrive magnitude), as shown in the "Maximum Transient Duration vs. Reset Threshold Overdrive" graph. This prevents spurious resets caused by switching noise or load transients, a key feature confirmed in the Applications Information section of the datasheet.

Is MAX6327UR26 pin-compatible with industry-standard supervisory ICs like MAX809 or MAX810?

Yes, MAX6327UR26 is pin-compatible with MAX809 and MAX810 in the SOT23-3 package: Pin 1 = VCC, Pin 2 = RESET, Pin 3 = GND. However, note that MAX809/MAX810 are active-low devices, whereas MAX6327UR26 is active-high push-pull-so direct substitution requires verification that the target µP accepts active-high reset. This compatibility is explicitly stated in the Features section and Pin Configuration diagram.