Linear taper and tap resolution for calibration loops
The DS3502U+T&R uses a linear taper, meaning each of the 128 taps increments the wiper-to-B resistance by an equal step of about 78 Ω across the 10 kΩ end-to-end resistance. The non-volatile memory stores the wiper position at power-down and restores it on the next power-up, so the calibration value survives a cycle without host intervention. Resistance tolerance is ±20% — typical for digital potentiometers — but the ratiometric tap-to-tap matching is far tighter, so the divider ratio accuracy is what matters in most applications.
I²C bus integration and address flexibility
Communication runs over the I²C interface, and the selectable address feature lets up to eight DS3502 devices share the same two-wire bus without address collision. This is useful in multi-channel systems where each channel's offset or gain needs independent trimming. This split-rail architecture means the wiper voltage can swing well above the logic supply, suiting it for applications like programmable current sources or high-side voltage dividers where the signal common is not at ground.
Temperature stability and industrial operating range
The temperature coefficient is ±4 ppm/°C typical — over a 100°C swing the resistance drifts by only about 0.04%, which is negligible for most trimming and calibration roles. The operating temperature range spans -40°C to 100°C, covering industrial and outdoor equipment without needing a commercial-grade part. Package is the 10-uMAX/uSOP, a 3 mm-wide, 0.118-inch pitch MSOP-style footprint. The narrow body saves board area in dense mixed-signal layouts, but the 0.5 mm lead pitch requires careful solder-paste stencil design for reliable reflow.
Lifecycle and compliance posture
Analog Devices lists the DS3502U+T&R as Active with ROHS3 compliance. No pin-compatible second source is documented in the available records.