Highly-integrated analog baseband for 3G WCDMA featured cellular phones

This paper presents an analog baseband circuit which is fully integrated in a 3G WCDMA digital baseband controller (modem) together with an application (multimedia) processor targeted featured cellular phones. The analog baseband is made by two (I and Q) 8b+ Analog-to-digital converters (ADCs), two (I and Q) 10b digital-to-analog converters with filters, a 10b auxiliary ADC, and a common circuit for the generation of an accurate bandgap reference voltage and biasing currents. To avoid performance degradations caused by crosstalk among the converters or from the nearby digital baseband activity, several design and layout precautions have been taken. All performance are guaranteed in mass production from −40 to +130 °C. The analog baseband converters are designed at 2.5 V supply in a 65 nm CMOS process with double oxide and MIM capacitor options. Total power consumption and area are 32.8 mW and 1.8 mm2, respectively.