Compact low-power FPGAs add flexible logic to motor-control boards
Programmable logic can simplify motion-control hardware, and the ForgeFPGA™ family from Renesas Electronics gives designers a compact, low-power way to add interface bridging, timing control, and supervisory logic.
Deterministic timing, interface glue, and fast supervisory logic can add overhead to the main controller in servo and inverter electronics. The ForgeFPGA™ range is well suited for supporting functions, such as protocol conversion, glue logic, edge processing, and power sequencing. This maps well to encoder adaptation, control-path housekeeping, safety interlocks, and interface bridging in motor and motion-control boards around the main control microcontroller (MCU).
For example, the ForgeFPGA family is suitable for encoder adaptation while leaving the control path intact and safe. The FPGAs can also support board-level supervisory and interlock logic, as well as bridge different interfaces to the main control MCU.
The ForgeFPGA family is well suited for industrial designs. SLG47912 has 1120 look-up tables and 40 general-purpose input/outputs (GPIO). The SLG47920 and SLG47921 have 2240 look-up tables. The SLG47920 has 32 GPIOs, and the SLG47921 has 40 GPIOs.
Software flow is the most significant part of the value. ForgeFPGA is supported by the free Go Configure Software Hub and ForgeFPGA Workshop, which allow engineers to choose between graphical design entry or developing designs in Hardware Description Language (HDL). The program can support design creation, simulation, programming, synthesis, bitstream generation, and debug all-inside-one workflow. This lowers friction if a motor-control design requires quick logic changes.
The development hardware is notably capable for rapid prototyping and validation. The SLG4DVKGOCONF Go Configure Development Board supports read, emulation, and programming functions, and the hardware manual adds three programmable power sources with configurable overcurrent protection, up to 32 digital pattern generator channels, and up to 16 analog waveform generator channels. It is then possible to prototype and validate support logic around motion-control hardware, not just configure the FPGA itself in this way.
The SLG47912V-SKT and SLG47921V-SKT use ForgeFPGA Socket Card with an LQFN-48 socket, SLG47920V-SKT uses a Socket Card with an LQFN-40 socket, and SLG47912C-SKT and SLG47921C-SKT use a Socket Card with a WLCSP-48 socket. All socket-card variants have onboard 4-Mbit SPI flash, PMOD connectors, standalone boot and power connectors, and a clock generator ranging from 2.5kHz to 200MHz.