US 3,960,010 A · Analog-digital converter for a resistance bridge

Abstract

Apparatus which provides a digital signal which represents the unbalance in a resistance bridge. The apparatus includes a source of direct-current voltage which is applied alternately and repetitively with opposite polarity to input terminals of the bridge. An amplifier is connected to the bridge output terminals. Analog-to-digital converters are connected to the output of the amplifier in such a way that one converter is connected to the amplifier output at a time when a positive voltage is applied to the bridge input and another converter is applied to the amplifier output at the time that a negative voltage is applied to the bridge input. A count is provided which represents the difference in the digital signals provided by the two converters. Such output is unaffected by any initial unbalance in the amplifier and is also not responsive to thermo-electrically generated electromotive forces.

Claims4

Dependent claims

Apparatus for providing a digital signal representative of the unbalance of a resistance bridge comprising:

a resistance bridge having input means and output means,
means for applying first and second direct-current voltages of opposite polarity but equal amplitude alternately and repetitively to said input means,
amplifier means connected to said output means,
analog-to-digital converter means responsive to said amplifier means,
counting means controlled by said converter means,
and means controlling said counting means to count in one sense while said first voltage is applied to said input means and in the opposite sense while said second voltage is applied to said input means.

3 more elements

Dependencies are inferred from the claim text.

Analog-digital converter for a resistance bridge

Life of this patent

Analog-digital converter for a resistance bridge

Life of this patent

Abstract

Claims4