Logarithmic taper digital pot with on-chip temperature sensor
The DS1841N+ is a 22kOhm digital potentiometer with 128 taps and a logarithmic taper, packaged in a 10-TDFN exposed pad (3x3mm). The log taper makes it a natural fit for audio gain control or optical attenuation where the human ear or photodetector response is logarithmic, not linear. Non-volatile memory means the wiper position is retained at power-up without a host microcontroller re-initializing it each cycle — useful in set-and-forget bias or calibration circuits.
Supply range, interface, and temperature sensor integration
Operates from 2.7V to 5.5V and over -40°C to +100°C, covering the industrial temperature band. The I²C interface supports a selectable address, so multiple DS1841N+ devices can share the same bus without address conflicts. The on-chip temperature sensor allows the host to read die temperature over the same I²C bus — a feature that can compensate for the ±250ppm/°C temperature coefficient in precision attenuation applications. Tolerance is ±20% — the end-to-end resistance is specified loosely, but the ratiometric tap accuracy (the step-to-step matching) is typically tighter, which is what matters for the attenuation ratio.
The exposed pad is also the ground connection. Supplied in tube packaging, surface-mount. The narrow 0.5mm pitch of the TDFN package means a solder stencil with appropriate aperture ratio is needed to avoid bridging during reflow.
Lifecycle and compliance
ROHS3 compliant, no exemptions that would complicate EU or UKCA market access. The DS1841N+ is a single-source part; a BOM hedge would require a board spin to a different package or pinout.