Analog Devices Inc./Maxim Integrated MAX6166BESA

Overview

MAX6166BESA 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 (VOUT + 200mV) to 12.6V, and draws only 100–120µA quiescent current-ideal for high-accuracy ADC biasing in portable instrumentation.

For engineers reviewing the MAX6166BESA datasheet, MAX6166BESA pinout, MAX6166BESA application, or MAX6166BESA equivalent, key selection criteria include its 200mV max dropout at 1mA, no external capacitor requirement, 27µV_p-p (0.1Hz–10Hz) noise, 76dB ripple rejection at 120Hz, and SO-8 package compatibility with space-constrained, battery-powered precision analog systems.

Technical Context

The MAX6166BESA 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 stability capacitors, enabling direct use with capacitive loads up to 1µF without oscillation risk.

This series-mode reference features supply-current independence (ΔI_IN/ΔV_IN ≤ 8.0µA/V), stable operation under line/load transients, and guaranteed performance across the full industrial temperature range-making it suitable for metrology-grade signal conditioning where long-term drift (<80ppm/1000hr) and hysteresis (125ppm) are tightly controlled.

Key Specifications

Pinout & Package

MAX6166BESA 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 and must remain floating. Pin 2 is IN (input voltage), Pin 4 is GND (ground reference), and Pin 6 is OUT (precision 2.5V reference output).

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 offers superior board-area efficiency (no capacitor needed), tighter load regulation (0.5mV/mA), and lower 0.1–10Hz noise-making it optimal for space-limited, low-noise, moderate-load applications where ±5mV accuracy is sufficient.

Availability

MAX6166BESA is available at Aetrix Electronics and suitable for portable instrumentation, industrial transmitters, and medical data acquisition systems requiring stable component supply with guaranteed long-term availability and RoHS-compliant packaging.

Supply support for MAX6166BESA 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, mixed-signal, and power-management ICs for demanding industrial, medical, and communications applications.

The MAX6161–MAX6168 family was engineered specifically for high-accuracy, low-power, low-dropout voltage referencing in battery-operated and space-constrained systems-emphasizing zero external components, ultra-low quiescent current, and guaranteed industrial-temperature performance.

FAQ

What is the maximum load current that MAX6166BESA can source while maintaining specified accuracy?

MAX6166BESA can source up to 5mA while maintaining its specified load regulation of 0.5–0.9mV/mA and output voltage accuracy. At 5mA load, the worst-case deviation from nominal 2.500V is ≤4.5mV (0.9mV/mA × 5mA), remaining within the ±5mV initial accuracy band. This makes MAX6166BESA suitable for driving multiple ADC reference inputs or op-amp bias networks simultaneously.

Does MAX6166BESA require an external output capacitor for stability?

No, MAX6166BESA does not require an external output capacitor for stability due to internal compensation. It remains stable with capacitive loads from 0 to 1µF. Adding a 0.1–1µF ceramic capacitor improves transient response during step-load changes but is optional-enabling true capacitor-free operation in ultra-dense layouts where every mm² matters.

What is the minimum input voltage required for MAX6166BESA to regulate at 2.500V output?

The minimum input voltage for MAX6166BESA is VOUT + 200mV = 2.7V, per datasheet specification. At 1mA load, dropout voltage is guaranteed ≤200mV, meaning regulation is maintained down to VIN = 2.7V. Below this, output voltage drops linearly with input; operation below 2.7V is not recommended for precision reference use.

How does the temperature coefficient of MAX6166BESA compare to the 'A' grade variant?

MAX6166BESA has a temperature coefficient of 4–10ppm/°C, whereas the MAX6166AESA variant is rated at 2–5ppm/°C. The 'B' grade trades tighter tempco for cost efficiency while retaining identical pinout, package, and electrical interface-making it ideal for applications where ±5mV initial accuracy is acceptable and drift contribution must stay below 25µV/°C.

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

Yes, MAX6166BESA can sink up to 2mA of load current. Its sinking capability is specified with 1.5–4mV/mA load regulation, meaning output voltage shifts ≤8mV (4mV/mA × 2mA) when sinking full 2mA. This supports active pull-down configurations, such as biasing current-sink DACs or interfacing with logic-level shifters requiring reference-based termination.