Analog Devices Inc./Maxim Integrated MAX6166BESA+T

Overview

MAX6166BESA+T from Maxim Integrated is a precision, low-dropout, micropower series voltage reference IC delivering a stable 2.500V output with ±5mV initial accuracy and 4–10ppm/°C temperature coefficient over –40°C to +85°C. It sources up to 5mA, sinks 2mA, operates from V_OUT + 0.2V to 12.6V, and features 200mV max dropout at 1mA - ideal for high-accuracy ADC biasing in portable instrumentation.

For engineers reviewing the MAX6166BESA+T datasheet, MAX6166BESA+T pinout, MAX6166BESA+T application, or MAX6166BESA+T equivalent, key selection criteria include its guaranteed 2.500V output tolerance, ultra-low 100–120µA quiescent current, no-external-capacitor stability, 27µV_p-p (0.1–10Hz) noise, and SO-8 package compatibility with space-constrained, battery-powered precision analog systems.

Technical Context

The MAX6166BESA+T employs a proprietary curvature-correction circuit and laser-trimmed thin-film resistors to achieve low thermal drift and high initial accuracy. Its internal compensation eliminates need for external capacitors, enabling direct integration into compact layouts without stability trade-offs.

As a three-terminal series-mode reference, it draws supply current virtually independent of input voltage (≤8.0µA/V variation), unlike shunt-mode devices requiring external biasing resistors. It supports sourcing and sinking load currents while maintaining tight regulation under line and load transients.

Key Specifications

Pinout & Package

MAX6166BESA+T is housed in an 8-pin SO (Small Outline) package with exposed pad not electrically connected. Pins 1, 3, 5, 7, and 8 are No Connect (N.C.), internally unconnected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF5025IDR and ADR3425ARJZ-R7, MAX6166BESA+T offers the best balance of 2.5V precision, ultra-low 100µA supply current, and capacitor-free operation - making it uniquely suitable for space- and energy-constrained portable instrumentation where layout simplicity and battery longevity are primary design drivers.

Availability

MAX6166BESA+T is available at Aetrix Electronics and suitable for portable precision DMMs, industrial data acquisition modules, and battery-powered sensor transmitters requiring stable component supply with full traceability and extended lifecycle support.

Supply support for MAX6166BESA+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.

The MAX6161–MAX6168 family was engineered specifically for high-accuracy, low-power voltage referencing in portable and space-constrained systems - emphasizing micropower operation, low dropout, and capacitor-free stability.

FAQ

What is the guaranteed initial accuracy of the MAX6166BESA+T over temperature?

The MAX6166BESA+T guarantees ±5mV initial output voltage error at +25°C, with total error over –40°C to +85°C remaining within ±5mV plus drift from its 4–10ppm/°C temperature coefficient. This translates to ≤±0.21mV additional drift across the full range, resulting in worst-case total error of ±5.21mV - sufficient for 12-bit ADC reference applications without trimming.

Does the MAX6166BESA+T require an external output capacitor for stability?

No, the MAX6166BESA+T is internally compensated and does not require an external output capacitor for stability. It remains stable with capacitive loads up to 1µF, but even 0pF load is acceptable. This eliminates a common BOM item and saves PCB area - a key advantage in ultra-compact portable designs where the MAX6166BESA+T is frequently deployed.

What is the minimum input voltage required for the MAX6166BESA+T to maintain regulation at 5mA load?

The MAX6166BESA+T requires a minimum input voltage of V_OUT + dropout voltage. At 5mA load and +25°C, its dropout is typically 100mV (max 200mV). Therefore, minimum input is 2.500V + 0.100V = 2.600V (worst case: 2.700V). The device is fully specified from V_OUT + 0.2V to 12.6V, confirming reliable operation down to 2.7V in most real-world conditions.

How does the supply current of the MAX6166BESA+T vary with input voltage?

The MAX6166BESA+T exhibits ≤8.0µA/V variation in quiescent supply current across its input range (V_OUT + 0.2V to 12.6V). At 2.7V input, I_IN is ~100µA; at 12.6V, it rises by ≤79µA - remaining below 180µA. This near-constant current behavior simplifies power budgeting and distinguishes it from shunt references whose current scales linearly with supply voltage.

Can the MAX6166BESA+T sink current, and what is its maximum sink capability?

Yes, the MAX6166BESA+T can both source and sink current. It sinks up to 2mA while maintaining output regulation, with load regulation specified at 1.6–5mV/mA in sink mode. This bidirectional capability allows use in active bias networks, current-source references, and circuits requiring dynamic load matching - extending utility beyond basic reference applications.