This article describes details for constructing a 1-Wire Barometer which will work on a Dallas Semiconductor Corporation 1-Wire network. This design differs from the popular Version 1.1a in that it has more than twice the resolution. - David W. Bray
1-Wire Barometer - 5/10 Volt Design
"The circuit requires an additional power source other than that of the 1-Wire network. The MPX4115 requires about 7 ma of current. This is more than a 1-Wire network can provide without an elaborate circuit to store parasitic power from the 1-Wire network for short burst of current for pressure measurements."
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