SPS Fast BCT Calibration J Spencer T Levens

SPS Fast BCT Calibration J. Spencer, T. Levens, M. Gasior J. Spencer 23/04/21

(Equipped with VFC) LS 2: Relocation LSS 5 to LSS 3 (Equipped with VFC) SPS FBCT LS 2: DAB to VFC LS 2: TRIC to VFC LS 2: DAB to VFC LS 2: DAB to VFC

Run 3 Specification • Proton intensity - 5 e 9 - 2. 2 e 11 charges • System design sensitive up to 3 e 11 charges - single shot / MDs • Transfer line to ring • Injection lines - absolute 3% with 1% relative bunch to bunch • Dump lines - absolute with 1% relative bunch to bunch • Circulating beams - bunch by bunch and total - absolute 1% • Operational experience 0. 3% • System designed to meet 0. 1% • Decay over first turns • Bunch by bunch 100 turns • Absolute 2% with 1% relative bunch to bunch

BCT Types • BCTF couples to beam • BCTW couples to image current Images: M. Krupa, T. Levens BCTF BCTW

BCT Signal Chain

Electronics Upgrade Summary • Redesign of BCTW Head amplifier • Upgrade to modern chip • Optimised pulse response • Redesign of Distribution amplifier • DAB -> VFC System • Modular • Compatible with BCTW and BCTF • Pulsed Current Source Calibration for BCTW and BCTF type transformers • There is no absolute calibration of Fast BCTs • Currently cross calibrated with DCCT

BCTW Head Amplifier

BCTW Head Amplifier – Normalised Frequency Response

BCTW Head Amplifier Pulse Response

Electronics Upgrade Summary • Redesign of BCTW Head amplifier • Upgrade to modern chip • Optimised pulse response • Redesign of Distribution amplifier • DAB -> VFC System • Modular • Compatible with BCTW and BCTF • Pulsed Current Source Calibration for BCTW and BCTF type transformers • There is no absolute calibration of Fast BCTs • Currently cross calibrated with DCCT

Distribution Amplifier • DAB -> VFC • Condition signal for digital integration • Cover the full range of intensities • Compatible with BCTW and BCTF • Modular approach • Ensure Protection of VFC FMC ADC

Distribution Amplifier - Outline

Dual BCTW Distribution Amplifier

Distribution Amplifier

Distribution Amplifier Pulse Response

BCTW Full Amplifier Chain

Electronics Upgrade Summary • Redesign of BCTW Head amplifier • Upgrade to modern chip • Optimised pulse response • Redesign of Distribution amplifier • DAB -> VFC System • Modular • Compatible with BCTW and BCTF • Pulsed Current Source Calibration for BCTW and BCTF type transformers • There is no absolute calibration of Fast BCTs • Currently cross calibrated with DCCT

Calibrator • Generate a defined current pulse with 0. 01% (100 ppm) repeatability • Accurately measure generated current • Remotely monitor generated current • Calibrate both BCTW and BCTF transformers • Calibrate up to four transformers from a single system

Working Principle • Fixed generated current • Customisable current by changing Rref • Referenced to positive supply • Current is approximately

Current Measurement – Half Bridge • 0 V Method • Measure reference voltage to determine generated current 1 mv = 1 ppm RHB = 100 kΩ , 0. 01%, ± 0. 2 ppm TCR Rload = 10Ω , 0. 01%, ± 0. 2 ppm TCR

Measured Current Pulse BCTW – 10Ω - 1000 m. A BCTF – 50Ω - 200 m. A

Stability • • Amplitude deviation from nominal value over a 50 μS period Sampled at 10 Hz for 90 hours in lab conditions. BCTW σ =4. 00 ppm BCTF σ = 4. 03 ppm BCTW – 10Ω - 1000 m. A BCTF – 50Ω - 200 m. A

Calibrator PCB Design FPGA Controller Analogue Calibrator

Dual BCTW/BCTF Calibrator

BA 3 BCTW Data 12/04/2021 • First data from SPS ring • Injection intensity ~1 e 11

Calibration • Calibration current sent to transformer calibration winding • Full signal chain response measured • Fit curve to response • Extrapolate to t=0

BA 3 Low Gain Calibration • Goodness of fit parameters

GUI • Remote control / monitoring • Monitoring • Current generation • Supply voltages • Temperature

Project status • Transfer lines & SPS • Full system installation complete • LHC Ring • Calibration system installed • Awaiting permission to install amplifiers on system B • LHC Dump • Full system installation complete

Thank you!