Struck Documentation
SIS8300-KU
MTCA.4 Digitizer
Page 11 of 92
The sensor signals are measured by the 24-bit ΣΔ-ADC LTC2493, which is connected to the
Kintex Ultrascale FPGA via an I²C interface.
The schematic of the ADC temperature sensor circuitry is illustrated below.
Note:
please refer to section 7.5.5 for a description of the I²C interface register
Please refer to device datasheet for additional information on the LTC2493 chip.
A software example can be found on the Struck product DVD under:
sisdvd_xxxxxx\sis8xxx and DWC\sis8300L\software\tests\adc_temp
2.7
DAC
A part of the SIS8300-KU versions comes with the 250 MSPS MAX5878 dual DAC chip.
The dual DAC can be used to control the Vectormodulator on the DWC8VM1
Downconverter/Vectormodulator RTM over the Zone 3 connector for example. The two DAC
channels can be routed to two front panel SMA outputs also (stuffing option). The table in
section 10.2 (ordering options) lists a number of DAC configurations of the SIS8300-KU.
Modules configured as DAC to FP outputs route the two DAC outputs over signal
conditioning stages to the two front panel SMA connectors.
The default range of the DAC
outputs over the SMA connectors is -1V,…,+1V into a 50 Ω load.
On modules configured with DAC to Z3, the outputs of the DAC are directly connected to the
Zone 3 connector without any additional components. Since each DAC channel outputs two
complementary currents, appropriate signal conditioning has to be done on the µRTM.
Refer to the datasheet of the MAX5878 for further information.