The invention provides a capillary tube pressure measuring device, comprising a singlechip
system, a current-to-
voltage circuit, an A / D conversion circuit, a
signal processing system, a display circuit and a
serial communication circuit, wherein the singlechip
system controls the whole
machine; the current-to-
voltage circuit converts input pressure current signals into
voltage signals; an input end of the A / D conversion circuit is connected with the current-to-voltage circuit and the singlechip system; a circuit of the
signal processing system is connected with the singlechip system; an input end of the display circuit is connected with the singlechip system; and the
serial communication circuit is connected with the singlechip system. The pressure measuring device adopts the singlechip system to accomplish the
data acquisition of pressure and temperature; the
signal processing system realizes complicated iterative
algorithm, thereby improving the precision and execution efficiency of the system; a
communication interface not only has the
serial communication between the
signal processing system and an external computer, but also has the
data transmission between a singlechip and the display circuit. The pressure measuring device has the advantages of small volume, convenience for carrying,
high pressure measuring precision, accurate and rapid measured data, real-time monitoring and display, etc., which can be used for monitoring the pressure in oil-gas wells.