Corrector Power Supply Controller Upgrade

Taiwan Photon Source TPS commissioned D-TACQ to build the Corrector Power Supply Controller CPSC, for fast orbit feedback control. The CPSC features eight 20-bit analog outputs, and 24 bit analog readbacks, fiber-optic data links and an embedded EPICS process controller for supervisory functions and data monitoring. The full consignment of CPSC units was delivered to TPS in 2013 in time for first light 2015. Since then, CPSC units have been in continuous use at TPS.

TPS staff were concerned that, as a custom design, CPSC would quickly become obsolete. They also wanted some performance enhancement and cost reduction, so they contracted with D-TACQ to design and produce "CPSC2", an updated slot-compatible version. The first CPSC2 units were tested and shipped in May 2019.

Key requirements for CPSC2 are:

  • Hardware back-compatibility with CPSC, must work in the same power supply crate.
  • Increase fast orbit feedback packet rate from 10kHz to 30kHz
  • Eliminate obsolete components.
  • Reduce cost where possible.

D-TACQ identified that the old FPGA board and Single Board Computer (ARM-5) were end of life, and could easily be replaced with a modern ZYNQ module. This way, we can use our standard mainline firmware - both gateware and embedded software. The custom ADC and DAC modules are still the best choice, and D-TACQ designed a new motherboard to fit the existing backplane slot, accept the same ADC, DAC modules, but replace FPGA and SBC with a single PICOZED module.

The new system has a number of advantages:

  • ZYNQ System on chip with combined FPGA and Microprocessor (ARM-9) eliminates the complexity of running PCIe on the motherboard and saves FPGA resource. The SOC is both simpler, cheaper and has higher throughput than the system it replaces.
  • Enables a faster packet processing chain using two ZYNQ Multi Gigabit Transcievers MGT.
  • A third MGT is in place to allow upgrade to White Rabbit timing.
  • System uses D-TACQ standard embedded software, common to the entire ACQ400 range, easy to keep up to date (currently running Linux kernel 4.14, Buildroot user land and EPICS7 IOC).

Significant cost reduction is achieved by:

  • Replacing two modules (FPGA, SBC) with a single COTS module (Avnet PICOZED).
  • Replacing the 20bit DAC device with 18bit, and omitting the passive thermal stabilization.
  • Reducing the ADC channel count from 32 to 16 channels.

In the future, TPS has the option to upgrade the existing 20-bit systems to the new FPGA architecture, since it will be both possible and cost effective to retrofit the high-value DAC-20 modules, ADC-32 modules and thermal stabilization to CPSC2 motherboards, allowing the old modules to take advantage of the latest firmware improvements.

D-TACQ manufactures a range of off the shelf high performance data acquisition hardware and systems. The systems are highly programmable and can be adapted to meet many requirements, but where this is not enough of course we can advise on custom systems for an exact fit. Modular custom systems allow the possibility for through-life extension and enhancement.