摘要 |
A trimming circuit and method of trimming is provided for offset and temperature drift trimming of an op amp or voltage reference device, having an input stage, on at least two different temperatures. The trimming circuit has a current source stage, having first and second current sources which are trimmed at a first temperature, in a first step, to balance the currents of the first and second current sources. The two current sources are configured to be selectively connected, in a second step and at the first temperature, to the offset-control terminal(s) of the input stage and thereby to trim the output of the input stage. The first and second current sources also have different temperature coefficients and are interchangeable with other current sources to facilitate changing, in a third step, the temperature coefficient of one of the two current sources to facilitate offset trimming at a second temperature.
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