Analog Devices Inc. ADR520BRT-R2

Overview

ADR520BRT-R2 from Analog Devices is a high-precision shunt voltage reference delivering 2.048 V output with ±0.2% initial accuracy, 40 ppm/°C max temperature coefficient, and 14 μV_p-p (0.1–10 Hz) output noise. It operates from 50 μA to 15 mA over −40°C to +85°C and requires no external capacitor-enabling use in portable data acquisition and battery-powered instrumentation.

For engineers reviewing the ADR520BRT-R2 datasheet, ADR520BRT-R2 pinout, ADR520BRT-R2 application, or ADR520BRT-R2 equivalent, key selection criteria include its SOT-23-3 package compatibility with LM4040/LM4050, trim terminal for ±0.5% output adjustment, and stable operation with any capacitive load without compensation.

Technical Context

The ADR520BRT-R2 implements a bandgap-based shunt reference architecture that sums a forward-biased V_BE (negative TC) with a ΔV_BE-derived proportional-to-absolute-temperature (PTAT) voltage (positive TC) to achieve near-zero net temperature drift. Its three-terminal configuration (V+, V−, TRIM) supports both positive and negative precision reference topologies.

It functions as a two-terminal device when TRIM is unconnected, but the dedicated TRIM pin enables post-assembly calibration of system-level errors without degrading temperature coefficient performance. The device maintains stability across full operating current (50 μA–15 mA) and load capacitance ranges, eliminating need for external frequency compensation.

Key Specifications

Pinout & Package

ADR520BRT-R2 is housed in a 3-lead SOT-23-3 (RT-3) package per JEDEC TO-236-AB, with 2.20 mm × 1.35 mm body size, 0.95 mm height, and gull-wing leads. Thermal resistance θ_JA = 270°C/W on standard 2-layer FR-4.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040C20IDCKR, ADR520BRT-R2 delivers 2.5× better initial accuracy and 2.5× lower tempco-critical for metrology-grade systems-while ADR520BKS-R2 offers identical performance in a 40% smaller footprint at the cost of reduced thermal dissipation capability.

Availability

ADR520BRT-R2 is available at Aetrix Electronics and suitable for portable instrumentation, industrial process transmitters, and energy metering systems requiring stable component supply with guaranteed long-term continuity.

Supply support for ADR520BRT-R2 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The ADR520BRT-R2 belongs to Analog Devices' precision voltage reference product line, engineered for high-accuracy, low-noise, and low-power applications in portable, industrial, and energy measurement systems.

FAQ

What is the output voltage tolerance of the ADR520BRT-R2 over temperature?

The ADR520BRT-R2 maintains 2.048 V output with ±0.2% initial accuracy at 25°C and a maximum temperature coefficient of 40 ppm/°C across −40°C to +85°C. This results in a worst-case total error of ±0.2% + (125°C × 40 ppm/°C) = ±0.2% + 0.5% = ±0.7% over full industrial temperature range, confirmed by Table 2 and Figure 15 in the Rev. E datasheet.

Can the ADR520BRT-R2 be used in a negative reference configuration?

Yes, the ADR520BRT-R2 supports negative reference operation by connecting V− to the system's positive rail and V+ to the regulated negative node, as shown in Figure 20 of the datasheet. In this mode, it provides a precise −2.048 V reference with identical accuracy, tempco, and noise performance as in positive mode.

Does the ADR520BRT-R2 require an external capacitor for stability?

No, the ADR520BRT-R2 is internally compensated and remains stable with any capacitive load-from 0 pF to >10 μF-without requiring external bypass capacitors. This is explicitly stated in the General Description and Applications sections, and verified by stability testing across load conditions in Figures 13–14.

How is the TRIM pin used on the ADR520BRT-R2?

The TRIM pin on the ADR520BRT-R2 accepts an external resistor network (e.g., 10 kΩ potentiometer between V+ and V−) to adjust output voltage over ±0.5% without affecting temperature coefficient or noise. Figure 21 shows implementation with AD5273; the trim range is guaranteed and does not require recalibration after adjustment.

What is the minimum operating current for the ADR520BRT-R2 at −40°C?

The ADR520BRT-R2 guarantees stable operation down to 50 μA across the full industrial temperature range (−40°C to +85°C), as specified in Table 2 and Absolute Maximum Ratings. At −40°C, this minimum current ensures proper bandgap circuit biasing and reference regulation, validated in Figure 2 reverse characteristics plot.