Analog Devices Inc. AD5245BRJZ100-R2

Overview

AD5245BRJZ100-R2 from Analog Devices is a 256-position I²C-compatible digital potentiometer in SOT-23-8 package with 100 kΩ end-to-end resistance, ±1 LSB integral nonlinearity (INL), 45 ppm/°C resistance temperature coefficient, and 2.7 V to 5.5 V single-supply operation. It replaces mechanical potentiometers in precision analog adjustment circuits such as LCD VCOM tuning and sensor transducer calibration.

For engineers reviewing the AD5245BRJZ100-R2 datasheet, AD5245BRJZ100-R2 pinout, AD5245BRJZ100-R2 application, or AD5245BRJZ100-R2 equivalent, key selection criteria include I²C address flexibility (AD0 pin), shutdown mode (zero-power wiper-to-B short), midscale power-on default, and guaranteed monotonicity across –40°C to +125°C.

Technical Context

The AD5245BRJZ100-R2 implements a 256-tap resistor ladder controlled via standard-mode I²C (400 kHz max), supporting both rheostat (A–W or B–W) and potentiometer divider (A–W–B) configurations. Its internal wiper register retains setting during active operation and resets to 0x80 (midscale) on power-up.

It features programmable shutdown (SD bit), midscale reset (RS bit), and dual-device bus addressing via AD0. Terminal voltage compliance is bounded by VDD and GND, with clamping diodes protecting A/B/W pins against overvoltage-no external protection required when supply sequencing follows GND → VDD → signal inputs.

Key Specifications

Pinout & Package

AD5245BRJZ100-R2 is housed in a compact 2.9 mm × 3 mm SOT-23-8 package, optimized for space-constrained PCB layouts in portable and automotive electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5245BRJZ100-R2, AD5243BRMZ100 offers dual-channel integration at identical performance and package size, while MCP45HV51-104E/MS trades I²C compatibility for 12 V terminal tolerance and SPI simplicity-neither is pin-compatible, but both serve overlapping trimming functions with distinct system-level trade-offs.

Availability

AD5245BRJZ100-R2 is available at Aetrix Electronics and suitable for LCD panel tuning, sensor calibration, RF bias control, and automotive trim applications requiring stable component supply across extended temperature and long product lifecycles.

Supply support for AD5245BRJZ100-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, serving precision instrumentation, industrial automation, and communications markets.

The AD5245 belongs to Analog Devices' precision digital potentiometer family, engineered for reliable, low-drift analog adjustment in harsh environments where mechanical potentiometers fail-targeting automotive, medical, and industrial control systems.

FAQ

What is the power-up behavior of the AD5245BRJZ100-R2?

The AD5245BRJZ100-R2 powers up with its wiper preset to midscale (code 0x80), delivering 50 kΩ between A and W and 50 kΩ between W and B in potentiometer mode. This deterministic start-up state eliminates undefined output conditions and removes the need for host firmware initialization before first use. The internal power-on circuit ensures this behavior across all valid supply voltages (2.7 V to 5.5 V) and temperatures (–40°C to +125°C), making AD5245BRJZ100-R2 suitable for safety-critical or unattended systems.

Does the AD5245BRJZ100-R2 support multiple devices on the same I²C bus?

Yes, the AD5245BRJZ100-R2 supports up to two devices on a shared I²C bus using the AD0 pin to configure the LSB of the 7-bit slave address. With AD0 tied to GND, the address is 0x2C; with AD0 tied to VDD, it becomes 0x2D. This dual-address capability enables coordinated trimming of two related analog paths-such as brightness and contrast in an LCD backlight driver-without requiring separate I²C buses or multiplexers. No additional address pins or external logic are needed for this configuration.

What is the maximum allowable voltage across terminals A, B, and W of the AD5245BRJZ100-R2?

The AD5245BRJZ100-R2 specifies that voltages at terminals A, B, and W must remain within the GND to VDD range-i.e., no terminal may exceed VDD or drop below GND. This limitation is enforced by internal ESD clamping diodes. Exceeding these bounds forward-biases those diodes, potentially powering VDD unintentionally or injecting current into the substrate. Therefore, the absolute maximum voltage difference between any two of A, B, or W is constrained by the applied VDD; for example, with VDD = 5 V, VA–VB must stay ≤5 V and ≥0 V. This design simplifies protection but requires proper supply sequencing (GND → VDD → signals).

How does shutdown mode affect the resistance and power consumption of the AD5245BRJZ100-R2?

In shutdown mode (activated by setting the SD bit in the I²C command byte), the AD5245BRJZ100-R2 opens the A terminal and shorts the wiper (W) to terminal B. This yields an effective resistance of ~100 Ω (dominated by wiper contact resistance) between W and B, and infinite resistance between A and W or A and B. Supply current drops to 0.01 µA to 1 µA-reducing total power dissipation to <5 nW at 5 V. Crucially, the wiper register contents are preserved, so exiting shutdown restores the prior setting without host reprogramming. This makes AD5245BRJZ100-R2 ideal for battery-powered systems needing intermittent analog adjustment.

Can the AD5245BRJZ100-R2 be used in potentiometer mode with bipolar signals?

No-the AD5245BRJZ100-R2 does not support true bipolar operation. While the A–B voltage polarity is unrestricted (VA and VB may be swapped or reversed relative to each other), all three terminals (A, B, W) must remain within the GND-to-VDD window. That is, no terminal may go below GND or above VDD. This means the device cannot handle AC signals centered at 0 V unless GND is biased to mid-supply (e.g., using a virtual ground). For true bipolar analog signal adjustment, a dedicated rail-to-rail digital potentiometer or external level-shifting circuitry is required. The AD5245BRJZ100-R2 is designed for unipolar DC or single-supply AC applications only.