STMicroelectronics has announced a new silicon pressure sensor capable of providing extremely high-resolution measurements of pressure – and therefore also of altitude – in a compact, thin package. The LPS001WP is a tiny (3×5 mm) silicon pressure sensor with an embedded 16-bit ADC, SPI and I2C interfaces and a supply voltage range of 2.2 V to 3.6 V.
According to the datasheet the device has an operating pressure range of 300–1100 millibar, corresponding to the atmospheric pressures between -750 and +9000 metres relative to sea level, and can detect pressure changes as small as 0,065 millibar, corresponding to 80 cm of altitude.
The LPS001WP will be manufactured in a small plastic land grid array (HCLGA) package and is guaranteed to operate over a temperature range extending from -40 °C to +85 °C. The package is holed to allow external pressure to reach the sensing element. Potential uses include sensing altitude to detect which floor of a building a device is (or was) on.
Vaporware, no samples, no stock.
The Bosch Sensortec BMP085 is slightly larger (5×5 mm) and has been out for some time. In its highest sensitivity mode it offers 0.01 hPa resolution and 0.03 hPa noise level. (Note: 1 millibar = 1 hPa). What really counts, though, is the accuracy and repeatability. In my comparison of two BMP085 devices, I found they differed by about 0.4 hPa up to 0.6 hPa in the same temperature & pressure environment, so the absolute accuracy of a given device would not be better than that. See also (datasheet):
http://www.bosch-sensortec.com/content/language1/downloads/BST-BMP085-DS000-05.pdf
and my measurements with this device at http://jeelabs.net/projects/cafe/wiki/Pressure_Plug_measurements
I have several of the SCP1000 sensors and also the TI Watch which has the SCP1000 sensor. Although I did not do as definitive testing as you have done, but with filtering I could measure +-1m. The TI watch has drifted from 55m to 33 m (48m actual) today with a change of ~4hPa. Which is not correct. Delta should be about 33 m.