Analog Devices Inc./Maxim Integrated MAX6858UK17D3+T

Overview

The MAX6858UK17D3+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.665V reset threshold (suffix '17'), and 150ms minimum reset timeout (suffix 'D3'). It monitors VCC, asserts active-low push-pull RESET on undervoltage or manual reset, and guarantees valid reset output down to VCC = +1.1V. It is designed for battery-powered medical and portable electronics requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6858UK17D3+T datasheet, MAX6858UK17D3+T pinout, MAX6858UK17D3+T application, or MAX6858UK17D3+T equivalent, this page delivers verified functional identity, exact pin roles, confirmed timing parameters, and validated alternative options - all specific to the MAX6858UK17D3+T variant with 1.665V threshold, 150ms timeout, and no watchdog or manual reset inputs.

Technical Context

The MAX6858UK17D3+T is a fixed-function supervisory IC without MR or WDI inputs - its pinout omits manual reset and watchdog functionality entirely. It relies solely on VCC monitoring and internal timeout logic to assert RESET when supply voltage falls below 1.665V, holding the signal low for ≥150ms after VCC recovers above threshold.

Its architecture includes an internally trimmed bandgap reference, precision comparator, and RC-based timeout generator. Immunity to short VCC transients (e.g., ≤40µs at 100mV overdrive) and guaranteed operation down to VCC = +1.1V enable robust use in low-voltage, noise-sensitive systems where supply stability cannot be assumed.

Key Specifications

Pinout & Package

MAX6858UK17D3+T uses a 5-pin SOT23 package with internally connected pins (I.C.) for enhanced noise immunity. Pins 1 and 2 are internally tied and must be connected to GND per datasheet guidance. No MR or WDI pins are present - this variant is dedicated to VCC-only monitoring.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3836K33DBVR and MAX6361LUR29+T, the MAX6858UK17D3+T delivers the lowest supply current (170nA vs. µA-range), tightest threshold match for 1.8V systems (1.665V), and smallest impact on battery runtime - making it optimal for disposable or long-life medical sensors where every nanoamp counts.

Availability

MAX6858UK17D3+T is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign loggers, portable pulse oximeters, and handheld medical diagnostic tools requiring stable component supply across multi-year production cycles.

Supply support for MAX6858UK17D3+T 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, medical, and communications applications.

The MAX685x family was engineered specifically for ultra-low-power supervisory functions in battery-critical medical and portable electronics, prioritizing nanoscale current consumption and guaranteed low-VCC reset validity over feature expansion.

FAQ

What is the exact reset threshold voltage of the MAX6858UK17D3+T?

The MAX6858UK17D3+T has a factory-trimmed reset threshold voltage of 1.665V, with ±2.5% tolerance over temperature (–40°C to +85°C). This value is defined by the '17' suffix in the part number and is confirmed in Table 2 (Threshold Suffix Guide) of the official datasheet. The MAX6858UK17D3+T does not support adjustable thresholds or external resistor networks.

Does the MAX6858UK17D3+T include a manual reset (MR) input or watchdog timer (WDI)?

No, the MAX6858UK17D3+T does not include MR or WDI functionality. Per the Selector Guide and Pin Configurations section, MAX6858 variants omit both pins - pins 1 and 2 are internally connected (I.C.) and must be tied to GND, while MR and WDI are absent. This distinguishes it from MAX6861–MAX6869 or MAX6864–MAX6869 families. The MAX6858UK17D3+T provides VCC monitoring only.

What is the guaranteed minimum reset timeout period for the MAX6858UK17D3+T?

The MAX6858UK17D3+T guarantees a minimum reset timeout period of 150ms, with typical and maximum values of 225ms and 300ms respectively (per Table 4, Reset Timeout Periods, D3 option). This timeout begins when VCC rises above the 1.665V threshold and ensures the reset signal remains asserted long enough for complete microprocessor initialization.

Can the MAX6858UK17D3+T operate reliably below 1.8V supply voltage?

Yes, the MAX6858UK17D3+T is fully specified from VCC = 1.2V to 5.5V and guarantees valid RESET assertion down to VCC = +1.1V. Its 170nA typical supply current at 1.8V and operational capability at 1.2V make it suitable for direct connection to partially discharged Li-ion cells or low-dropout regulators feeding 1.8V logic domains.

What package type and lead finish does the MAX6858UK17D3+T use?

The MAX6858UK17D3+T uses a 5-pin SOT23 package with lead-free (RoHS-compliant) finish, indicated by the '+T' suffix. It is compatible with standard SOT23 reflow profiles and requires no special handling beyond standard moisture sensitivity level (MSL) 1 guidelines. The package footprint matches industry-standard supervisory IC footprints for drop-in layout reuse.