Analog Devices Inc./Maxim Integrated MAX6742XKZD3

Overview

MAX6742XKZD3 from Maxim Integrated is a low-power dual-voltage microprocessor supervisor IC that monitors primary V_CC supply and provides an independent power-fail comparator. It features factory-trimmed 2.313V V_CC1 reset threshold, 150ms minimum reset timeout, 6µA supply current, and operates in the -40°C to +85°C range. It is used in portable battery-powered systems requiring reliable power sequencing and early brownout detection.

For engineers reviewing the MAX6742XKZD3 datasheet, MAX6742XKZD3 pinout, MAX6742XKZD3 application, or MAX6742XKZD3 equivalent, key selection criteria include its dedicated PFI/PFO interface for external voltage monitoring, open-drain RESET output with internal 50kΩ pullup to V_CC1, SC70-5 package footprint, and compatibility with 1.2V–5.5V operating voltage ranges.

Technical Context

The MAX6742XKZD3 implements a dual-supply supervision architecture with one fixed-threshold monitor on V_CC1 (2.313V) and a separate power-fail comparator referenced to a precise 488mV internal reference. Its PFI input accepts externally scaled voltages down to 0.468V (min), and PFO asserts immediately-without timeout-when PFI falls below threshold.

It uses BiCMOS process technology (249 transistors), supports manual reset detect via the open-drain RESET pin (with internal 50kΩ pullup), and guarantees valid RESET state while either V_CC1 or V_CC2 remains above 1.2V. The device does not monitor V_CC2; per datasheet, MAX6742 is a single-supply monitor with PFI/PFO functionality only.

Key Specifications

Pinout & Package

MAX6742XKZD3 is housed in a 5-pin SC70-5 package (2.0mm × 1.25mm, 0.65mm pitch), optimized for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervision applications.

Compared with MAX6745XKZD3, the MAX6742XKZD3 offers identical supervision accuracy and PFI responsiveness but trades push-pull drive for open-drain flexibility and internal pullup convenience; versus TPS3808G12DBVR, it adds essential power-fail pre-warning at the cost of slightly higher quiescent current.

Availability

MAX6742XKZD3 is available at Aetrix Electronics and suitable for portable/battery-powered equipment, multivoltage systems, and industrial handheld terminals requiring stable component supply and long-term lifecycle support.

Supply support for MAX6742XKZD3 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, automotive, and computing applications.

The MAX6736–MAX6745 family was designed specifically for low-power, space-constrained microprocessor systems requiring dual/threshold supervision and early power-fail detection without external components.

FAQ

What is the exact reset threshold voltage for MAX6742XKZD3?

The MAX6742XKZD3 has a factory-trimmed V_CC1 reset threshold of 2.313V, with guaranteed tolerance of ±1.5% across the -40°C to +85°C temperature range. This value is defined by the "Z" suffix in the part number per Table 2 of the datasheet and applies exclusively to the primary V_CC1 supply monitor.

Does MAX6742XKZD3 monitor both V_CC1 and V_CC2 supplies?

No. Unlike dual-supply variants (e.g., MAX6736/MAX6740), the MAX6742XKZD3 monitors only V_CC1. It does not include a V_CC2 input. Its secondary function is the dedicated power-fail comparator (PFI/PFO), not a second voltage monitor.

What is the purpose of the internal 50kΩ pullup on the RESET pin of MAX6742XKZD3?

The internal 50kΩ pullup on the RESET pin of MAX6742XKZD3 eliminates the need for an external pullup resistor in most applications. It ensures the RESET line defaults high when not asserted, simplifies PCB layout, reduces BOM count, and enables direct connection to µP reset pins requiring active-low open-drain signaling.

Can MAX6742XKZD3 be used to monitor negative supply voltages?

Yes. The PFI input can monitor negative voltages using the circuit in Figure 4B of the datasheet: a resistor network referenced to V_CC scales the negative rail so PFI sees a positive voltage relative to GND. When the negative supply collapses, PFO asserts, enabling controlled shutdown before system instability.

What is the reset timeout period for MAX6742XKZD3, and how is it determined?

The MAX6742XKZD3 has a 150ms minimum reset timeout period, denoted by the "D3" suffix. This is a factory-programmed, temperature-stable delay (±10% over -40°C to +85°C) that ensures the RESET signal remains asserted long enough for the microprocessor to complete its internal power-on reset sequence reliably.