web2019/content/experiment-control/control-loops.md

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Sinara 8452 DSP "Stabilizer"

The Sinara 8452 DSP is a CPU-based dual-channel digital signal processing platform, particularly suited to fast servo applications. It can be controlled by Kasli or work stand-alone with Power-over-Ethernet (PoE) supply.

• 400MHz STM32H743ZIT6
• dual 16bit ADC with x2, x5, x10 PGA (2MS/s)
• 16bit AD5542A DAC (1µs settling time)
• PoE supply
• 10/100Base-T Ethernet
• connectors for optional analog front-end (AFE) module
• IDC connectors for BNC-IDC/SMA-IDC extension for digital IO and aux analog inputs and outputs

It can be used as a general-purpose PID controller. Several AFE extensions are under development including high current power supply for magnets.

More information

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• dual channel
• SPI ADC
• SPI DAC
• fixed AFE gains
• 500 kHz rate, timed
• < 2 µs latency, unmatched

• f32 IIR math
• generic biquad (second order) IIR filter
• anti-windup
• derivative kick avoidance
• configurable output limits

To purchase this controller, email sales@m-***s.hk. We also offer firmware customizations and development of new features. Note that features that are not implemented in the open source code above (e.g. control from Kasli) are not supported unless purchased separately.

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Sinara 8451 Thermostat

The Sinara 8451 Thermostat is a precision 2-channel temperature controller based on the Maxim MAX1968 driver, capable of driving 6W into a TEC or resistive heater. The sensor interface is based on 24-bit AD7172 ADC.

Temperature stability better than 1mK can be achieved; typically the temperature drift is around 300µK peak-to-peak over 10 hours.

Specifications:

• Channel count: 2
• Sensor: 10k NTC thermistor
• Load (heater/TEC) drive: up to 8W (+-2A with 4V compliance)
• Form factor: 3U module or stand-alone aluminum enclosure.
• Output connectors: Sensor and load connect via either terminal block connector on the front panel or via internal 100mil pin-header.
• Programming interface: Ethernet accessible via RJ45 connector on the front panel
• Power supply: +12V DC (1.5A max) supplied either by a front-panel barrel connector, via 100mils Zotino connector, or PoE (up to 30W).
• STM32 MCU

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SU-Servo

With the SU-Servo feature of ARTIQ, the Sinara 4410 DDS (which has fine amplitude control) can be used in combination with the 5108 Sampler to form a laser intensity servo. In this application, the 4410 DDS drives AOMs and photodiodes are connected to the 5108 Sampler to monitor laser intensities. When ordering your system, specify that you want SU-Servo integrated into the gateware.

See the Sinara Core page for the relevant devices (1123 Carrier "Kasli", 5108 Sampler, and 4410 DDS "Urukul").

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