Texas Instruments Corporation

Chuck Payne

Larry J Wofford

William M Andreycak

Robert Monroe

An electronic device includes a conductive member disposed within an insulative package. The conductive member is formed from a lead frame used to form the interconnection pins for the device. The conductive member includes an elongated, folded sense element portion having a known resistance. The sense element portion is disposed between two sets of conductive lead portions extending from the conductive member forming pins used to provide a current to the device for sensing. An integrated circuit disposed within the package includes a differential amplifier having differential inputs connected to bond pads on the integrated circuit. The bond pads are connected to spaced-apart tap points of the sense element via conductive bond wires, so that the combination of the sense element and the differential amplifier forms a trans-impedance amplifier. The gain of the differential amplifier is controlled to be proportional to the magnitude of a reference voltage generated by a bandgap voltage reference circuit. The reference voltage varies with temperature such that the overall gain of the trans-impedance amplifier is constant over temperature. The nominal gain of the differential amplifier is established by an on-chip resistance, which is trimmed using fuse-programmable trim cells that are programmed via operational package pins during a pre-operation trim procedure.

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Cary, NC, United States of America

Chuck Payne