Functional overview
The ADC is built of several functions which are used for analog acquisition of external analog signals, the demodulation of an external PDM bit-stream, and post processing of the results. The super-set of functionality is documented here. Please refer to the device specific section for specific implementation details. At least one TMADC instance exists in all function subsets. Optional features are:
Delta-Sigma ADC (DSADC)
External modulator support (EXMOD)
Fast Compare Comparator (FCC)
Converter Digital Signal Processor (CDSP)
ADC interface to GTM and eGTM (depending on the presence of GTM or eGTM)
Figure 1. ADC system interconnect
The block diagram gives an overview of how the ADC and its sub-functions are connected to the rest of the system. Please note that:
ADC has two bus slaves:
BPI slave connected to either CPB, COMPB or SPB.
All the ADC registers and memories are accessible through this interface
Note: Please check the device specific feature section which bus is connected.
AXI slave connected to LLI
Only the TMADC result, monitoring result, and timestamp registers can be read over this interface
Note: The Wait-for-read functionality is not supported over the AXI slave interface for TMADC
Note: The LLI connection is not available in all device variants, please check the device specific feature section.
Boundary flags from different ADC sub-functions are handled centrally and are connected to GTM and eGTM. In addition, FCC boundary flags are also connected to ports
TMADC receives on its monitoring sampler, low-precision band gap output voltage for conversion
TMADC results RES14 and RES15 are accessible by every MCS(GTM) over the ADI interface. The availability of a new result on this interface could be signaled by sending an interrupt directly from ADC to MCS(GTM)
TMADC supports the control of an external analog MUX with up to 8 analog inputs
To support external modulator demodulation (EXMOD), it can receive the data as well as clock from an external modulator. As an option, EXMOD can also provide its clock to the external modulator
The PWM signal for carrier generation is supported by DSADC and can receive the sign information from ports for carrier cancellation
There are 8 alarms which are connected to SMU. The same alarms can be sent as service requests to IR
Note: The number of alarms vary from device to device
Each sub-function can directly send service requests to IR:
TMADC has 6 service requests per instance and 4 global service requests
FCC has 2 service requests per instance
DSADC has 4 service requests per instance
EXMOD has 4 service requests per instance
CDSP has 3 service requests per instance
ADC has up to 64 input trigger lines, which are distributed to all the sub-functions. The sources of input triggers are:
Up to 36 triggers from GTM
Up to 12 triggers from eGTM
Up to 8 triggers from SCU(ERU)
Up to 7 triggers from ports
One trigger from carrier generator (DSADC)
Note: The number of triggers depends on the device configuration and the package variant used. The maximum number of all triggers is 64