Analog Devices Inc./Maxim Integrated MAX6730UTSD2+

Overview

MAX6730UTSD2+ from Maxim Integrated is a single-voltage microprocessor supervisor IC with active-low open-drain reset output, factory-set 2.925V VCC1 reset threshold, 1.1ms minimum reset timeout, and integrated watchdog timer featuring independent open-drain watchdog output. It monitors primary supply voltage in embedded systems requiring reliable power-on reset and lockup protection for ARM Cortex-M or PIC microcontrollers in industrial controllers.

For engineers reviewing the MAX6730UTSD2+ datasheet, MAX6730UTSD2+ pinout, MAX6730UTSD2+ application, or MAX6730UTSD2+ equivalent, key selection criteria include its 2.925V fixed VCC1 threshold, 1.1ms reset timeout, 14µA typical supply current at +3.6V, -40°C to +85°C operation, and SOT23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6730UTSD2+ implements a dual-mode watchdog timer: a 35s minimum startup delay after reset enables full system initialization, followed by a 1.12s minimum normal-mode timeout for rapid fault detection. Its reset logic asserts RST low when VCC1 drops below 2.925V (±1.5% over temperature), with 0.5% hysteresis and guaranteed validity down to VCC1 = +0.8V.

It features a dedicated manual reset input (MR) with 50kΩ internal pullup, 1µs minimum pulse width, and 100ns glitch rejection. The open-drain RST output requires an external pullup and sinks up to 3.2mA at VCC1 ≥ +4.5V while maintaining VOL ≤ 0.4V.

Key Specifications

Pinout & Package

MAX6730UTSD2+ is housed in a 6-pin SOT23-6 package (package code U6-1), footprint-compatible with industry-standard 2.9mm × 1.6mm land patterns (land pattern no. 90-0175). The package is RoHS-compliant and lead(Pb)-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6730UTSD2+, MAX6326UR29D3+ lacks watchdog and manual reset-reducing system reliability but saving cost and space-while TPS3808G125DBVR offers tighter threshold tolerance but demands additional passive components and has incompatible timing architecture.

Availability

MAX6730UTSD2+ is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics equipment, and smart metering applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6730UTSD2+ 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 industrial, automotive, and communications markets, with expertise in power management and supervisory circuits.

The MAX6730–MAX6735 family delivers single/dual/triple-voltage supervision with integrated watchdog timers specifically for µP-based systems needing high-reliability power monitoring in space-constrained, thermally demanding environments.

FAQ

What is the exact VCC1 reset threshold voltage for MAX6730UTSD2+?

The MAX6730UTSD2+ has a factory-set VCC1 reset threshold of 2.925V, with ±1.5% tolerance over the full -40°C to +85°C operating temperature range. This value is confirmed in Table 1 of the datasheet under suffix "S", and the device guarantees reset assertion when VCC1 falls below this level and deassertion when VCC1 rises above 2.925V + hysteresis (0.5% of threshold).

Does MAX6730UTSD2+ include a watchdog timer, and what are its timing parameters?

Yes, MAX6730UTSD2+ includes a dual-mode watchdog timer. It provides a minimum 35s startup delay after reset to allow system initialization, followed by a minimum 1.12s normal-mode timeout period. The watchdog output (WDO) is active-low and open-drain, asserting low if no edge is detected on WDI within the timeout window. These values are specified in the Electrical Characteristics table under "Watchdog Timeout Period".

What package type and pin count does MAX6730UTSD2+ use?

MAX6730UTSD2+ uses a 6-pin SOT23-6 package (package code U6-1), with dimensions 2.9mm × 1.6mm and standard land pattern 90-0175. Pin 1 is RST, Pin 2 is GND, Pin 3 is WDO, Pin 4 is MR, Pin 5 is WDI, and Pin 6 is VCC1. This matches the MAX6730/MAX6731 variant group per the Pin Configurations diagram.

Can MAX6730UTSD2+ monitor more than one supply voltage?

No, MAX6730UTSD2+ is a single-voltage supervisor designed exclusively to monitor VCC1. It does not monitor VCC2 or RSTIN inputs-the latter two are features of the MAX6732–MAX6735 variants. The "S" suffix in MAX6730UTSD2+ denotes the VCC1 threshold only (2.925V), and the device lacks pins for secondary voltage monitoring.

What is the reset output configuration of MAX6730UTSD2+ and how should it be interfaced?

MAX6730UTSD2+ features an active-low open-drain RST output (Pin 1), requiring an external pullup resistor to VCC1 or another logic rail. It sinks up to 3.2mA at VCC1 ≥ +4.5V with VOL ≤ 0.4V. For µPs with bidirectional reset pins, a 10kΩ series resistor between RST and the µP reset I/O prevents logic contention, as documented in Figure 5 of the datasheet.