Texas Instruments Incorporated
INTERLEAVING ERRORS SOURCES AND THEIR CORRECTION FOR RF DACS

Abstract:

Analog gain correction circuitry and analog switching clock edge timing correction circuitry can provide coarse correction of interleaving errors in radio-frequency digital-to-analog converters (RF DACs), such as may be used in 5G wireless base stations. The analog correction can be supplemented by digital circuitry configured to "pre-cancel" an interleaving image by adding to a digital DAC input signal a signal equal and opposite to an interleaving image created by the interleaving DAC, such that the interleaving image is effectively mitigated. Error correction control parameters can be periodically adjusted for changes in temperature by a controller coupled to an on-chip temperature sensor. A model useful for understanding the sources of error in interleaving DACs is also described.