Semiconductor pressure sensor and data processing device

Abstract

For example, to adjust an offset of a pressure sensor, there are provided an external resistor RE and an internal resistor circuit that is connected to both ends of RE and formed in a semiconductor chip such as a processor. The internal resistor circuit includes N pieces of internal resistors RI connected in series between both ends of RE, and (N+1) pieces of switches selecting one of voltages of respective nodes of the serial resistors and outputs the same as a signal. RE has a high absolute value precision of, e.g., several ten ohms to several hundred ohms, and RI has a high relative value precision of, e.g., several kilo-ohms. Therefore, an offset adjustment range is decided at a high absolute value precision mainly by RE, and with regard to the arrangement resolution, a high precision can be obtained along with the relative value precision of the RI.

1 - 10 . (canceled) 
     
     
         11 . A data processing device formed on a semiconductor substrate, the data processor comprising:
 first, second, and third terminals to which a pressure sensor is connected;   a plurality of resistance elements connected between the second terminal and the third terminal;   a plurality of switch elements connected to a connection portion of the plurality of resistance elements;   a first register that can store a first set value to make one switch element selected among the plurality of switch elements conductive;   an amplification circuit that receives the outputs of the first terminal and the selected one switch element;   a second register that can store a second set value to set the amplification ratio of the amplification circuit; and   an analog-digital conversion circuit to receive an output of the amplification circuit.   
     
     
         12 . The data processing device according to  claim 11 , further comprising:
 a bus;   a CPU connected to the bus; and   a memory that stores the first and second set values to be set by the first and second registers, wherein   the first and second set values are set from the memory to the first and second registers through the bus, in response to initialization of the data processing device.   
     
     
         13 . The data processing device according to  claim 12 , wherein
 the memory is a nonvolatile memory in which data can be written and deleted electrically, and   a first program to calculate the first and second set values, and an operation program to calculate a pressure from a signal from the pressure sensor are stored to the nonvolatile memory.   
     
     
         14 . The data processing device according to  claim 12 , wherein
 the data processing device is used in a manometer.   
     
     
         15 . The data processing device according to  claim 12 , wherein
 the data processing device is used in a vacuum cleaner.   
     
     
         16 . The data processing device according to  claim 12 , wherein
 the data processing device is used in a barometer.