Gas-sensing front-end for IAQ monitoring
The Renesas ZMOD4450AI1R is a metal-oxide gas sensor module designed for indoor air quality detection, communicating over an I²C bus. It targets applications like air purifiers, HVAC economizers, and demand-controlled ventilation where the sensor must resolve changes in volatile organic compound (VOC) concentration. Rated accuracy is ±2 % across the sensing range, but this figure is typical at the reference condition — the real error budget includes offset drift and sensitivity variation over the 0 °C to 25 °C operating band. At the temperature extremes the baseline resistance of the MOX element shifts, so the ±2 % number is a best-case anchor for the error stack, not a guaranteed limit across the full band.
Supply and interface constraints
The I²C output type means the sensor acts as a slave device; the bus pull-up resistors should be sized for the 1.7 V VDD level to keep the rise time within the 400 kHz Fast-mode spec. The LGA package measures 3.00 x 3.00 x 0.70 mm with a 0.50 mm pitch. The low profile suits space-constrained PCB layouts in duct-mounted or wall-plate sensor nodes. The exposed pad on the bottom side provides the thermal and electrical reference for the MOX heater — the PCB land pattern must include a thermal via array under the pad to sink the 13 mA heater current without local hot spots.
Renesas lists the ZMOD4450AI1R as Active in its product portfolio. No end-of-life notice or last-time-buy window has been issued as of the current date.