Analog Devices Inc. ADM6328-31ARTZ-R7

Overview

ADM6328-31ARTZ-R7 from Analog Devices is an ultralow-power, open-drain microprocessor reset circuit in a 3-lead SOT-23 package, designed to monitor 3.08 V supply rails with ±2.5% threshold accuracy over −40°C to +85°C. It asserts an active-low RESET signal within 20 µs of VCC falling below threshold, holds reset for ≥100 ms on power-up, and operates down to 1.0 V supply voltage-enabling reliable startup and brownout protection in portable microprocessor systems.

For engineers reviewing the ADM6328-31ARTZ-R7 datasheet, ADM6328-31ARTZ-R7 pinout, ADM6328-31ARTZ-R7 application, or ADM6328-31ARTZ-R7 equivalent, key selection criteria include its 1 µA max supply current, open-drain output requiring external pull-up, 3.08 V reset threshold with 6.3 mV hysteresis, and guaranteed operation across industrial temperature range.

Technical Context

The ADM6328-31ARTZ-R7 implements a precision bandgap-based voltage reference and comparator to detect VCC drops below its factory-trimmed 3.08 V threshold. Its internal 100 ms (min) / 185 ms (typ) reset timeout ensures stable power-up sequencing before releasing the microprocessor from reset.

As an open-drain device, it interfaces directly with bidirectional microprocessor reset pins using a single external pull-up resistor-supporting shared reset bus architectures without contention. Glitch immunity rejects negative-going VCC transients up to 200 mV for durations under 1 µs, per Figure 5.

Key Specifications

Pinout & Package

ADM6328-31ARTZ-R7 is housed in a JEDEC-compliant 3-lead SOT-23-3 (RT-3) package with 270°C/W junction-to-ambient thermal resistance. Pin 1 = GND, Pin 2 = RESET (open-drain), Pin 3 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809SEUR+T and TPS3808G30DBVR, ADM6328-31ARTZ-R7 provides the lowest quiescent current (1 µA vs. 2.5/1.6 µA), open-drain flexibility for shared reset buses, and factory-trimmed 3.08 V threshold-making it optimal for space-constrained, ultra-low-power, and multi-device reset coordination scenarios.

Availability

ADM6328-31ARTZ-R7 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, wireless IoT edge nodes, and embedded point-of-sale terminals requiring stable component supply and long-term lifecycle support.

Supply support for ADM6328-31ARTZ-R7 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide.

The ADM6328 series belongs to Analog Devices' Single Supply Monitors product line, engineered specifically for ultralow-power, precision voltage supervision in battery-operated and industrial embedded systems where reliability and minimal current draw are critical.

FAQ

What is the exact reset threshold voltage of ADM6328-31ARTZ-R7 at 25°C?

The ADM6328-31ARTZ-R7 has a nominal reset threshold voltage of 3.08 V at 25°C, with a guaranteed tolerance of ±2.5% (3.034 V to 3.126 V). This value is factory-trimmed and specified in Table 2 of the Rev. B datasheet, making ADM6328-31ARTZ-R7 suitable for precise supervision of 3.08 V rails without external calibration.

Does ADM6328-31ARTZ-R7 require an external pull-up resistor on the RESET pin?

Yes, ADM6328-31ARTZ-R7 features an active-low open-drain RESET output (Pin 2), which requires an external pull-up resistor to a valid logic-high voltage (e.g., 3.3 V or 5 V). Typical values range from 4.7 kΩ to 10 kΩ. This configuration enables wired-OR reset busing and compatibility with microprocessors that have bidirectional reset pins-key functionality not supported by push-pull alternatives like ADM6326-31ARTZ-R7.

What is the minimum VCC voltage at which ADM6328-31ARTZ-R7 can assert a valid RESET signal?

ADM6328-31ARTZ-R7 guarantees valid RESET assertion down to VCC = 1.0 V, as stated in the Operating Voltage Range specification. At VCC ≥ 1.2 V and ISINK = 100 µA, VOL is ≤0.4 V-ensuring a solid logic low. This capability allows ADM6328-31ARTZ-R7 to maintain system integrity during deep brownout conditions where other supervisors may release reset prematurely.

How does the reset timeout period of ADM6328-31ARTZ-R7 vary with temperature?

The reset active timeout period of ADM6328-31ARTZ-R7 ranges from 100 ms (minimum) to 280 ms (maximum) across −40°C to +85°C, with a typical value of 185 ms at 25°C. Figure 6 in the datasheet shows monotonic increase with temperature, reaching ~260 ms at +85°C. This variation is fully characterized and guaranteed-no derating or external timing components are needed for robust power-up sequencing.

Can ADM6328-31ARTZ-R7 be used to monitor a 3.3 V supply rail?

ADM6328-31ARTZ-R7 is specifically trimmed for 3.08 V threshold-not 3.3 V-and should not be used to supervise a nominal 3.3 V rail unless the actual operating voltage consistently stays below 3.08 V under all conditions. For 3.3 V supervision, Analog Devices offers ADM6348-33ARTZ-R7 (3.3 V threshold) or ADM6348-34ARTZ-R7 (3.4 V threshold), both in the same SOT-23-3 package and open-drain configuration as ADM6328-31ARTZ-R7.