ELE Times March 2017 ELE Times | Page 40

Design

What is new in

Analog and

Digital interfaces for High-speed data Converters

Recent advancements in high speed Data Converter sampling rates and bandwidth handling capabilities changed the way of interfacing the high speed ADCs and DACs with processors and FPGAs . The interface between the Data Converters and FPGA / Processors is moved from LVDS to JESD204B high speed serial interface . The technological advancements in data converters also provided with lot of system design advantages . The Giga sampling rate data converters are also called as RF sampling data converters as these data converters can directly handle RF frequencies enabling new possibilities in system architecture for Defence , Test & measurement and Communications market .

Purnachandar Poshala | Analog Applications Manager , Member Group Technical Staff | Texas Instruments India
What are the benefits of RF sampling high speed ADCs and DACs ?
For wide band digital receivers / transmitters , Test and measurement , Aerospace and defense , 5G mobile communication systems , 802.11ad Wi-Fi systems , higher bandwidth handling capability is a key feature to have and it can be enabled using the RF sampling ADCs and DACs . The example
Texas Instruments recently released ADC32RF45 ADC which can
support RF input frequencies upto 4GHz and supports sampling
rate upto 3GSPS which can be used to directly digitize the
L
options for these systems are ADC12J4000 which delivers an
band / S-band signals for defense radar systems . Similarly
instantaneous 2.0GHz bandwidth , ADC32RF45 which delivers
DAC38RF8x DAC can generate the RF outputs upto and beyond
1.5GHz instantaneous per channel bandwidth and DAC38RF8x
4GHz output frequency . These ADCs and DACs can provide the
which can provide more than 4GHz bandwidth .
true software defined radio capability with flexibility for frequency input and output selection , dynamically re-configure different frequencies and multi band processing . Direct RF
Sampling provides lots of flexibility through digital signal processing . These will enable system designers to re-use the same hardware for multiple platforms which reduces R & D costs .
For the receiver applications , ADC32RF45 RF sampling ADC can eliminate up to four intermediate frequency ( IF ) down-conversion stages in multi-band receivers , reduces board space up to 75 percent and allows to simultaneously processing multiple frequency bands . The below figure provides the top level functional diagram .
ELE Times | 40 | March , 2017