JAJSEY1 April 2019 ADC12DJ5200RF
ADVANCE INFORMATION for pre-production products; subject to change without notice.
The analog inputs of the ADC12DJ5200RF have internal buffers to enable high input bandwidth and to isolate sampling capacitor glitch noise from the input circuit. Analog inputs must be driven differentially because operation with a single-ended signal results in degraded performance. Both AC-coupling and DC-coupling of the analog inputs is supported. The analog inputs are designed for an input common-mode voltage (VCMI) of 0 V, which is terminated internally through single-ended, 50-Ω resistors to ground (GND) on each input pin. DC-coupled input signals must have a common-mode voltage that meets the device input common-mode requirements specified as VCMI in the Recommended Operating Conditions table. The 0-V input common-mode voltage simplifies the interface to split-supply, fully-differential amplifiers and to a variety of transformers and baluns. The ADC12DJ5200RF includes internal analog input protection to protect the ADC inputs during overranged input conditions; see the Analog Input Protection section. Figure 4 provides a simplified analog input model.
There is minimal degradation in analog input bandwidth when using single-channel mode versus dual-channel mode. Either analog input (INA+ and INA– or INB+ and INB–) can be used in single-channel mode. The desired input can be chosen using SINGLE_INPUT in the input mux control register.