Analog Devices Inc./Maxim Integrated MAX6719UTTZD3+

Overview

MAX6719UTTZD3+ from Maxim Integrated is a triple-voltage microprocessor supervisory circuit in 6-pin SOT23 package, monitoring VCC1 (4.625V threshold), VCC2 (3.075V threshold), and an externally adjustable RSTIN input (626.5mV reference). It asserts active-low open-drain reset for ≥210ms after any supply drop, supports manual reset and watchdog timer, and operates from -40°C to +85°C. It is used in multivoltage embedded systems requiring reliable power-up sequencing and brownout protection.

For engineers reviewing the MAX6719UTTZD3+ datasheet, MAX6719UTTZD3+ pinout, MAX6719UTTZD3+ application, or MAX6719UTTZD3+ equivalent, key selection criteria include its dual-supply monitoring with factory-trimmed thresholds, 210ms reset timeout, 14µA typical supply current at 3.6V, guaranteed reset validity down to VCC1/VCC2 = 0.8V, and compatibility with battery-operated and telecom equipment where low quiescent current and precise undervoltage detection are critical.

Technical Context

The MAX6719UTTZD3+ integrates three independent voltage monitoring paths: primary (VCC1), secondary (VCC2), and auxiliary (RSTIN), each with dedicated comparators referenced to internal precision bandgap references. Its reset logic combines OR-ed fault conditions - VCC1/VCC2 below threshold, RSTIN < 626.5mV, or MR assertion - triggering a monolithic timeout counter that holds RST low for exactly 210ms (min) after all monitored voltages recover.

It features an open-drain RST output referenced to VCC1, internal 50kΩ MR pullup, and a watchdog timer with dual-mode operation: 35s startup period post-reset followed by 1.12s normal timeout. The RSTIN input accepts external resistor-divider networks for third-supply monitoring down to 0.62V, with ≤25nA input leakage ensuring minimal loading.

Key Specifications

Pinout & Package

MAX6719UTTZD3+ uses a 6-pin SOT23-6 package (2.9mm × 1.6mm × 1.1mm), surface-mount, lead-free (+T suffix), with thermal pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6720UTTZD3+, the MAX6719UTTZD3+ provides open-drain RST for bus sharing and legacy µP compatibility, while TPS3808G33DBVR offers lower power but sacrifices the critical third-monitoring channel required in multivoltage SoC designs.

Availability

MAX6719UTTZD3+ is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLCs, portable medical devices, and set-top boxes requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for MAX6719UTTZD3+ 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, communications, and computing markets.

The MAX6715–MAX6729 family was designed specifically for space-constrained multivoltage systems needing precise, low-power, triple-rail supervision with factory-trimmed accuracy and robust glitch immunity.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6719UTTZD3+?

The MAX6719UTTZD3+ has a factory-trimmed VCC1 reset threshold of 4.625V (typical), with guaranteed limits of 4.500V (min) and 4.750V (max) over temperature. This value is encoded in the "TZ" suffix per Maxim's Reset Voltage Threshold Suffix Guide and is laser-trimmed during production to ensure ±1.5% accuracy without external components.

Does the MAX6719UTTZD3+ support monitoring a third supply voltage, and how is it configured?

Yes, the MAX6719UTTZD3+ supports third-supply monitoring via its RSTIN pin, which compares the applied voltage against an internal 626.5mV reference. To monitor a custom voltage (e.g., 1.2V), connect a resistor divider from the target rail to GND with RSTIN at the midpoint. The formula is V_{EXT_TH} = 626.5mV × ((R1 + R2)/R2), and input leakage <25nA ensures minimal error with standard 1% resistors.

What is the reset timeout period for the MAX6719UTTZD3+, and is it adjustable?

The MAX6719UTTZD3+ has a fixed minimum reset timeout period of 210ms, indicated by the "D3" suffix in its part number. This value is trimmed and guaranteed over temperature; it is not user-adjustable via external components. The timeout begins when all monitored supplies rise above their thresholds and ends 210ms later, ensuring sufficient time for µP initialization before release.

Is the RST output of the MAX6719UTTZD3+ push-pull or open-drain, and what are the implications?

The RST output of the MAX6719UTTZD3+ is open-drain, requiring an external pullup resistor to VCC1 or another logic rail. This allows wired-OR connection with other reset sources and compatibility with bidirectional µP reset pins. Unlike push-pull variants (e.g., MAX6720UTTZD3+), it cannot actively drive high but provides greater interface flexibility in multi-source reset architectures.

How does the MAX6719UTTZD3+ handle short VCC transients, and what is its immunity specification?

The MAX6719UTTZD3+ is immune to short negative-going VCC transients: for a 100mV overdrive below threshold, it tolerates glitches up to ~20µs without issuing a false reset. This immunity is inherent to its internal comparator architecture and does not require external filtering. A 0.1µF ceramic capacitor placed close to the VCC1 pin further enhances transient rejection in noisy environments.