Analog Devices Inc./Maxim Integrated MAX6854UK23D1+T

Overview

The MAX6854UK23D1+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, providing voltage monitoring, manual reset input (MR), and fixed 10ms minimum reset timeout. It asserts an active-low push-pull RESET when VCC drops below 2.23V (factory-trimmed threshold), during MR assertion, or at power-up/brownout - guaranteeing valid reset down to VCC = +1.1V. It targets ultra-low-power portable systems such as glucose monitors and battery-powered medical sensors where supply current <200nA is critical.

For engineers reviewing the MAX6854UK23D1+T datasheet, MAX6854UK23D1+T pinout, MAX6854UK23D1+T application, or MAX6854UK23D1+T equivalent, key selection criteria include its 2.23V reset threshold, 10ms reset timeout, 170nA typical supply current at 2.5V, immunity to sub-40µs VCC transients, and guaranteed operation across –40°C to +85°C.

Technical Context

This device integrates a precision voltage comparator with 2.5% threshold accuracy, a monolithic reset timeout timer, and a CMOS-compatible manual reset input with 10kΩ internal pullup. Its reset assertion logic combines VCC monitoring, MR edge detection (250ns delay), and glitch rejection (200ns), all operating without external components.

The push-pull active-low RESET output delivers VOL ≤ 0.3V at ISINK = 1.2mA (VCC ≥ 2.38V) and VOH ≥ 0.8×VCC at ISOURCE = 500µA, enabling direct interfacing with µP reset inputs. Its 170nA supply current remains stable across temperature (–40°C to +85°C) and supply voltage (1.2V to 5.5V), validated per Maxim's production test flow.

Key Specifications

Pinout & Package

MAX6854UK23D1+T uses a 5-pin SOT23 package (JEDEC MO-178AA), with pins arranged as follows (top view): Pin 1 = RESET (active-low push-pull), Pin 2 = GND, Pin 3 = MR (active-low manual reset), Pin 4 = GND, Pin 5 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3836K33DBVR and ADM6806-23ARTZ-R7, the MAX6854UK23D1+T offers 7× lower supply current and exact 2.23V threshold matching common low-voltage analog sensor rails, making it optimal for multi-year battery life in medical wearables where reset timing must be tightly controlled at sub-100ms intervals.

Availability

MAX6854UK23D1+T is available at Aetrix Electronics and suitable for glucose monitoring systems, patient vital sign monitors, and wireless sensor nodes requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for MAX6854UK23D1+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) designs precision analog and mixed-signal ICs for demanding industrial, medical, and communications applications, emphasizing low-power innovation and high-reliability manufacturing.

The MAX6854UK23D1+T belongs to Maxim's nanopower µP supervisory family, engineered specifically for battery-critical portable medical electronics where sub-200nA supply current and guaranteed reset behavior down to 1.1V are mandatory design requirements.

FAQ

What is the exact reset threshold voltage of the MAX6854UK23D1+T?

The MAX6854UK23D1+T has a factory-trimmed reset threshold of 2.23V, with ±2.5% tolerance over the full –40°C to +85°C temperature range. This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "23" corresponds to 2.23V. The MAX6854UK23D1+T maintains this threshold stability across supply voltages from 1.2V to 5.5V, enabling reliable brownout detection in low-voltage medical sensor rails.

Does the MAX6854UK23D1+T include a watchdog timer function?

No, the MAX6854UK23D1+T does not include a watchdog timer. It belongs to the MAX6854/MAX6855/MAX6856 subgroup, which provides only voltage monitoring and manual reset (MR) functionality. Watchdog capability is exclusive to MAX6864–MAX6869 variants (e.g., MAX6864UK23D1S+T). The MAX6854UK23D1+T pinout lacks WDI, and its functional diagram confirms absence of watchdog circuitry.

What is the reset timeout period for the MAX6854UK23D1+T?

MAX6854UK23D1+T has a fixed minimum reset timeout period of 10ms, indicated by the "D1" suffix in its part number. Per Table 4 (Reset Timeout Periods), D1 specifies 10ms (min), 15ms (typ), and 25ms (max). This timeout begins when VCC rises above 2.23V or MR is deasserted, ensuring sufficient hold time for µP internal initialization before release.

Is the MAX6854UK23D1+T pin-compatible with other SOT23-5 supervisory ICs?

MAX6854UK23D1+T is pin-compatible with the TPS3836/TPS3837/TPS3838 series per Maxim's datasheet Feature list, sharing identical pin 1 (RESET), pin 2 (GND), pin 3 (MR), pin 4 (GND), and pin 5 (VCC) assignments. However, it is not compatible with ADM6806 or MAX6861 variants due to differing RESET polarity or CT/WDI pin allocations. Always verify pin functions against the specific variant's pin description table.

What is the maximum VCC transient duration the MAX6854UK23D1+T can ignore?

The MAX6854UK23D1+T ignores VCC transients ≤40µs in duration when the overdrive is 100mV (i.e., VCC falls from 2.33V to below 2.23V). This immunity is documented in the "Maximum VCC Transient Duration vs. Reset Threshold Overdrive" graph (Figure MAX684 toc05) and ensures robust operation in systems with switching regulator noise. Transients exceeding this limit will trigger a reset pulse.