Analog Devices Inc./Maxim Integrated MAX6719UTSYD3+

Overview

MAX6719UTSYD3+ 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 monitored supply falls below threshold or manual reset is triggered, and features watchdog timer startup (35s min) and normal timeout (1.12s min). It supports multivoltage embedded systems requiring reliable power sequencing and brownout detection.

For engineers reviewing the MAX6719UTSYD3+ datasheet, MAX6719UTSYD3+ pinout, MAX6719UTSYD3+ application, or MAX6719UTSYD3+ equivalent, key selection criteria include dual/third-supply monitoring capability, guaranteed reset validity down to VCC1/VCC2 = 0.8V, low 14µA typical supply current at 3.6V, immunity to short VCC transients, and compatibility with manual reset, watchdog, and power-fail signaling in space-constrained designs.

Technical Context

The MAX6719UTSYD3+ integrates three independent voltage monitors: factory-trimmed VCC1 and VCC2 comparators (4.625V/3.075V thresholds) plus an adjustable RSTIN comparator referenced to a 626.5mV internal bandgap. Its reset logic combines OR-ed fault conditions - VCC1 undervoltage, VCC2 undervoltage, RSTIN undervoltage, or MR assertion - with a monolithic timeout timer ensuring minimum 210ms reset pulse width.

This device implements a dual-mode watchdog: a 35s minimum startup period after any reset event (power-up, MR, or watchdog timeout), followed by a 1.12s minimum normal timeout period triggered by the first valid WDI edge. All reset outputs are open-drain, requiring external pullup, and the IC guarantees correct reset state down to VCC1 or VCC2 = 0.8V.

Key Specifications

Pinout & Package

MAX6719UTSYD3+ uses a 6-pin SOT23-6 package with gull-wing leads, 1.27mm pitch, and 2.9mm × 1.6mm footprint - optimized for high-density PCB layouts in portable and embedded systems.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6719UTSYD3+, MAX6720UTSYD3+ offers stronger reset drive at the cost of wiring flexibility, while TPS3808G33DBVR reduces complexity and power but sacrifices triple-supply coverage - making MAX6719UTSYD3+ optimal for designs requiring adjustable third-rail monitoring with open-drain interoperability.

Availability

MAX6719UTSYD3+ is available at Aetrix Electronics and suitable for telecom power sequencing, industrial PLC I/O modules, network switch ASIC boot, and battery-backed data loggers requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature operation.

Supply support for MAX6719UTSYD3+ 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 precision analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The MAX6715–MAX6729 family was designed to replace discrete supervisory solutions in multivoltage embedded systems, delivering integrated triple-supply monitoring, watchdog, and manual reset in sub-3mm² SOT23 packages for space-constrained applications.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6719UTSYD3+?

The MAX6719UTSYD3+ has a factory-trimmed VCC1 reset threshold of 4.625V (typical), with tolerance of ±1.5% over temperature. This value is encoded in the 'SY' suffix per Maxim's Reset Voltage Threshold Suffix Guide and is guaranteed across the -40°C to +85°C operating range. The threshold triggers on the falling edge of VCC1 and initiates the 210ms reset timeout period.

Does the MAX6719UTSYD3+ support monitoring a third supply voltage, and how is it configured?

Yes, the MAX6719UTSYD3+ supports third-supply monitoring via its RSTIN pin, which references an internal 626.5mV bandgap. To configure, connect an external resistor divider from the target supply to GND, with the midpoint feeding RSTIN. The monitored threshold is calculated as V_{EXT_TH} = 626.5mV × (R1 + R2)/R2. This enables monitoring down to 0.62V without additional components.

What is the function of the MR pin on the MAX6719UTSYD3+, and what is its default state?

The MR (Manual Reset) pin on the MAX6719UTSYD3+ is an active-low input with an internal 50kΩ pullup to VCC1. When pulled low for ≥1µs, it forces the RST output low for the full 210ms timeout period. If left unconnected, MR remains high due to the internal pullup, disabling manual reset. It accepts TTL/CMOS logic levels and supports momentary switch interfacing without external debounce.

How does the watchdog timer operate on the MAX6719UTSYD3+, and what are its timeout periods?

The MAX6719UTSYD3+ implements a dual-mode watchdog timer: after any reset event (power-up, MR, or timeout), it enters a 35s minimum startup mode to allow full system initialization; upon detecting the first valid WDI edge, it switches to 1.12s minimum normal mode. WDI must see a rising or falling edge within this period to prevent reset assertion - ensuring both safe boot and responsive fault detection.

Is the MAX6719UTSYD3+ pin-compatible with other devices in the MAX6715–MAX6729 family?

Yes, the MAX6719UTSYD3+ shares the same 6-pin SOT23-6 package and pinout with MAX6715, MAX6716, MAX6719, MAX6720, MAX6721, and MAX6722. Pin functions (RST, GND, MR, VCC2, VCC1, RSTIN) are identical across these variants. However, functional differences exist - e.g., MAX6715 lacks RSTIN, MAX6716 uses push-pull RST - so electrical compatibility must be verified per application requirements.