Patent ID: 9065467
Filing Date: 2015-06-23
Classification: H03M

Abstract:
1. A method for obtaining an AD conversion result of an n (where n: positive integer) bit extension for the resolution of an AD converter by a control circuit in a data processing system in which the AD converter and a programmable gain amplifier are included, the method comprising: dividing an input range of the AD converter by m (2 preparing a digital offset at which voltages at connection points of respective divided ranges are identical between the adjacent divided ranges, determining to which divided range an AD conversion result by the AD converter belongs with respect to an analog signal to be measured, amplifying an amp offset which defines a voltage range for each determined divided range as a voltage range for the input range of the AD converter by applying the amp offset and a designation of gain therefor to the programmable gain amplifier, converting the amplified signal by the AD converter, performing an n-bit extension and a division by actually measured gain of the programmable gain amplifier on a result of conversion thereof, and adding a corresponding digital offset of divided range to the conversion result, thereby obtaining an AD conversion result with a bit precision being n-bit extended.