Analog Devices Inc. AD5246BKS50-R2

Overview

AD5246BKS50-R2 from Analog Devices is a 128-position I²C-compatible digital resistor with 50 kΩ end-to-end resistance, SC70-6 package (2 mm × 2.1 mm), and ±0.25 LSB integral nonlinearity. It operates from 2.7 V to 5.5 V, draws 0.9 µA typical supply current at 3.3 V, and features 45 ppm/°C temperature coefficient - ideal for precision transducer biasing in automotive and industrial sensor modules.

For engineers reviewing the AD5246BKS50-R2 datasheet, AD5246BKS50-R2 pinout, AD5246BKS50-R2 application, or AD5246BKS50-R2 equivalent, key selection criteria include I²C address compatibility (0x5C), rheostat-mode wiper resistance stability, midscale power-on default, low 1 nA common-mode leakage, and guaranteed monotonicity across –40°C to +125°C.

Technical Context

The AD5246BKS50-R2 implements a 7-bit RDAC latch decoded to select one of 128 linearly spaced wiper positions across a 50 kΩ thin-film resistor element. Its I²C interface uses a fixed 7-bit slave address (0x5C) with R/W bit, supports repeated start/write operations, and requires no external pull-up voltage translation when interfaced with 3.3 V or 5 V masters.

Internal ESD protection includes series input resistors and parallel Zener structures on SDA/SCL pins. Terminal voltage compliance is clamped by forward-biased diodes between VDD/GND and terminals A/W/B - limiting VB and VW to GND ≤ V ≤ VDD, with absolute max ratings of ±5 mA continuous terminal current.

Key Specifications

Pinout & Package

AD5246BKS50-R2 is housed in an ultracompact SC70-6 package (2.0 mm × 2.1 mm × 0.9 mm), optimized for space-constrained PCB layouts in portable and automotive modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital resistor applications.

Compared with MAX5402EUA+T and MCP4018T-E/OT, AD5246BKS50-R2 delivers optimal balance of I²C compatibility, industry-leading 45 ppm/°C stability, and smallest SC70-6 footprint - making it preferred for space- and precision-critical automotive and industrial calibrations.

Availability

AD5246BKS50-R2 is available at Aetrix Electronics and suitable for automotive sensor calibration, RF amplifier biasing, and industrial optical gain trimming requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD5246BKS50-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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design and manufacturing expertise spanning precision instrumentation, industrial automation, and automotive electronics.

The AD5246 family was engineered specifically for replacing mechanical potentiometers in high-reliability, space-constrained applications - emphasizing low power, wide temperature operation, and I²C simplicity for sensor interface and bias control.

FAQ

What is the I²C slave address of the AD5246BKS50-R2?

The AD5246BKS50-R2 uses a fixed 7-bit I²C slave address of 0x5C (1011100b), with the R/W bit appended as the eighth bit. This address is hardwired and not configurable. The device responds to write commands when the eighth bit is 0 and to read commands when it is 1 - enabling direct integration into standard I²C systems without address conflict concerns. AD5246BKS50-R2 supports repeated start conditions for rapid sequential updates.

Does the AD5246BKS50-R2 retain its wiper setting after power cycling?

No, the AD5246BKS50-R2 is volatile and resets to midscale (code 0x40) on each power-up. It does not include EEPROM or nonvolatile memory. However, its ultralow 0.9 µA supply current at 3.3 V enables practical constant-bias operation - maintaining the wiper setting indefinitely while powered, with negligible battery drain. AD5246BKS50-R2 is intended for systems where firmware reinitializes settings at boot or where continuous bias is feasible.

What is the maximum allowable voltage across terminals W and B of the AD5246BKS50-R2?

The AD5246BKS50-R2 specifies that voltages applied to terminals W and B must remain within GND ≤ VW, VB ≤ VDD. Exceeding this range forward-biases internal ESD clamp diodes, potentially causing unintended current flow or damage. Absolute maximum ratings allow only ±5 mA continuous current between W and B - at low codes (e.g., 0x00), RWB can drop below 150 Ω, so users must limit applied voltage to <0.75 V to stay within safe current limits. AD5246BKS50-R2 is not rated for rail-to-rail terminal operation.

Can the AD5246BKS50-R2 be used in potentiometer mode (three-terminal connection)?

No, the AD5246BKS50-R2 is configured exclusively for rheostat (two-terminal) operation - connecting only terminals W and B (or W and A) to form a variable resistance path. Terminal A is internally connected to the top of the resistor string but is not brought out as a functional pin on the SC70-6 package. The datasheet confirms only W and B are active resistor terminals; A is not accessible. AD5246BKS50-R2 is designed for applications requiring a digitally adjustable series resistance, not three-terminal voltage division.

How does the 45 ppm/°C temperature coefficient affect system-level accuracy in a 50 kΩ application?

With a 45 ppm/°C tempco, the AD5246BKS50-R2 exhibits ±0.36% resistance change over an 80°C span (e.g., 25°C to 105°C). For a 50 kΩ nominal value, this equals ±180 Ω drift - significantly tighter than mechanical potentiometers (>1000 ppm/°C) and sufficient for most sensor calibration and biasing tasks. Combined with ±0.25 LSB INL, total unadjusted error remains under ±0.5% across –40°C to +125°C. AD5246BKS50-R2's thin-film construction ensures this stability is repeatable and process-controlled.