Analog Devices Inc./Maxim Integrated MAX6704YKA+

Overview

MAX6704YKA+ from Maxim Integrated is a single-supply microprocessor supervisory IC in 8-pin SOT23 package, providing dual active-low/high push-pull reset outputs, an adjustable power-fail comparator (PFI/PFO), manual reset input (MR), and a reset-based watchdog timer with 1.6s timeout. It monitors +2.12V to +2.25V supply rails and guarantees valid reset down to VCC = 1V for critical µP power monitoring in white goods and networking equipment.

For engineers reviewing the MAX6704YKA+ datasheet, MAX6704YKA+ pinout, MAX6704YKA+ application, or MAX6704YKA+ equivalent, key selection criteria include its Y-suffix 2.19V reset threshold (–40°C to +85°C), complementary reset outputs, PFI threshold of 618mV (typ), 140ms reset timeout, and guaranteed operation at VCC ≥ 1.0V - all confirmed for this exact variant.

Technical Context

The MAX6704 implements a dual-stage reset generator with independent assertion/deassertion timing: VCC falling below 2.19V triggers a low-going RESET and high-going RESET̅ simultaneously, each held for 140ms after recovery. Its power-fail comparator uses an internal 0.62V reference with PFI input leakage <±50nA and 6mV hysteresis, enabling precise early-warning detection of secondary supply collapse.

The integrated watchdog operates on a reset-triggered basis - a 1.6s timeout on WDI inactivity forces a full reset pulse (not a latched WDO), eliminating need for external logic. MR input includes 50kΩ internal pullup and 100ns glitch rejection, supporting pushbutton or logic-level reset initiation without external components.

Key Specifications

Pinout & Package

MAX6704YKA+ is housed in an 8-pin SOT23 package (package code K8+2), measuring 2.9mm × 1.6mm × 1.1mm, RoHS-compliant and lead-free (indicated by '+' suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6704YKA+, MAX6708YKA+ removes watchdog dependency while retaining identical supervision accuracy and dual-output flexibility, whereas TPS3808G12DBVR trades feature depth for lower cost and smaller footprint in minimal-reset applications.

Availability

MAX6704YKA+ is available at Aetrix Electronics and suitable for critical µP power monitoring, intelligent instruments, and telecommunications infrastructure requiring stable component supply across industrial temperature ranges.

Supply support for MAX6704YKA+ 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, communications, computing, and consumer applications.

The MAX6701–MAX6708 family delivers compact, low-power microprocessor supervision with integrated power-fail detection and configurable reset architectures for space-constrained embedded systems.

FAQ

What is the exact reset threshold voltage for MAX6704YKA+ across temperature?

The MAX6704YKA+ has a nominal VCC reset threshold of 2.19V at –40°C to +85°C, with min/max of 2.11V/2.27V over –40°C to +125°C. This Y-suffix variant is specifically calibrated for +2.2V supply rails and exhibits ±60ppm/°C temperature coefficient, ensuring stability across industrial operating conditions. The threshold is guaranteed and production-tested per Maxim's Electrical Characteristics table.

Does MAX6704YKA+ provide independent watchdog output (WDO) like other MAX670x devices?

No, MAX6704YKA+ does not include an independent watchdog output (WDO). Unlike MAX6701–MAX6707 variants, it implements a reset-based watchdog: timeout on WDI inactivity directly asserts the RESET/RESET̅ outputs for the full 140ms timeout period. This eliminates need for external OR-ing logic but means no separate watchdog status signal is available.

How is the power-fail comparator configured on MAX6704YKA+?

The MAX6704YKA+ power-fail comparator uses pin 4 (PFI) as high-impedance input referenced to an internal 0.62V bandgap. To set a custom trip point (e.g., 3.0V), connect PFI to a resistor divider from the monitored rail to GND, sized so voltage at PFI falls below 0.62V at desired threshold. Pin 5 (PFO) provides active-low push-pull output that can drive µP interrupts directly.

What are the timing relationships between RESET and RESET̅ outputs on MAX6704YKA+?

On MAX6704YKA+, RESET (pin 7) and RESET̅ (pin 8) are true complements: when RESET is low, RESET̅ is high, and vice versa. Both outputs assert/deassert simultaneously with identical 140ms timeout delay after VCC crosses the 2.19V threshold. No propagation skew exists between them - they share the same internal reset generator and driver stage.

Can MAX6704YKA+ operate reliably at VCC = 1.2V, and what happens to reset behavior below 2.19V?

Yes, MAX6704YKA+ guarantees valid RESET/RESET̅ output states down to VCC = 1.0V. Below 2.19V, RESET goes low and RESET̅ goes high, remaining asserted until VCC rises above 2.19V and holds for ≥140ms. At VCC < 1.0V, the outputs enter high-impedance state - design requires external pull-down on RESET if CMOS input drift must be avoided.