Wide-Band Spice Model of the High-Speed and High-Voltage Transformers for the CCD220

Jorge RomeroUniversity of Málaga (http://www.uma.es)

Javier Reyes (Presenter), Mark DowningEuropean Southern Observatory, ESO (http://www.eso.org)

Scientific Detector Workshop 2013. 7-11 October 2013. Florence, Italy10 October 2013 1Spice Model of the High-Voltage Transformers for the CCD220

10 October 2013 2Scientific Detector Workshop 2013. 7-11 October 2013. Florence, Italy

ESO Adaptive Optics Camera• CCD220 is and EMCCD• High-Voltage clock key element for electron multiplication• At the core of the high-voltage clock there is a high-speed transformer

Spice Model of the High-Voltage Transformers for the CCD220

99,0

1T

snarT

1S

DNG

Fp001

31CpaC

DNG

1DreifitcerFR

3

26

74

8,5,12U

3

26

74

8,5,1

6U

f

f

~~~//

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tesIH_V

tesOL_V

hctiws

Fp001

21C

VH2ihpRDCC

DNG

Peak Detector

Peak Detector

High-Voltage PID controller• MOSFET switching at the primary of the transformer• PID controller

10 October 2013 3Scientific Detector Workshop 2013. 7-11 October 2013. Florence, Italy

Measurement and Vector Fitting• The S-Parameter measurements have the interesting

property that it is not necessary to perform neither shorts nor opens on the network during the measurement process (unlike other kind of representations, say Z or Y parameters)

• One can translate S parameter to Z or Y parameters

Spice Model of the High-Voltage Transformers for the CCD220

TWO-PORTNETWORK

[S]

a1 a2

b1b2

V1 V2I1I2

10 October 2013 4Scientific Detector Workshop 2013. 7-11 October 2013. Florence, Italy

Spice Model of the High-Voltage Transformers for the CCD220

99,0

1T

snarT

1S

DNG

Fp001

31CpaC

DNG

1DreifitcerFR

3

26

74

8,5,12U

3

26

74

8,5,1

6U

f

f

~~~//

~~~//

tesIH_V

tesOL_V

hctiws

Fp001

21C

VH2ihpRDCC

DNG

Peak Detector

Peak DetectorVi_n

H12

-4.31265392e9/(s+3.9507498e9)-1.09143570e8/(s+1.0735469e9)+7.92278561e7/(s+1.0212672e8)-1.56746016e5/(s+1.6547306e7)-6.54319475e2/(s+8.5316223e4)+0.426917671Hb2 14.142136

50

R1

HI2 3.5355339

EV2 70.710678m

2.37189911e9/(s+3.9507498e9)-2.11755009e8/(s+1.0735469e9)-1.65850558e8/(s+1.0212672e8)-4.09919783e5/(s+1.6547306e7)+6.63947824e2/(s+8.5316223e4)+245.48159e-3

G_22 G21

1

G12

1

-3.35252967e9/(s+3.9507498e9)-5.94329189e8/(s+1.0735469e9)-3.64233892e7/(s+1.0212672e8)+1.56094954e5/(s+1.6547306e7)+1.19158183e2/(s+8.5316223e4)+7.5844235e-1

G_11

EV1 70.710678m

HI1 3.5355339

50

R2

Hb1 14.1421356

H21

-4.31265392e9/(s+3.9507498e9)-1.09143570e8/(s+1.0735469e9)+7.92278561e7/(s+1.0212672e8)-1.56746016e5/(s+1.6547306e7)-6.54319475e2/(s+8.5316223e4)+0.426917671

Vo_p

Vo_n

Vi_p

Very accurate modellingThe extracted model includes:• The effect of the magnetic coupling between the transformer

windings• The conductor losses• The interwinding parasitic capacitances• The stray capacitances of the PCB footprint and metal tracks

Model of the transformer

Frequency-response of the resonant circuit.

Fine tuning of the PID parameters possible

The Spice model

• The transformer’s behaviour was accurately modeled as a linear circuit in the Laplace Domain by a network of controlled current and voltage sources. Time-domain

simulation around the resonance frequency

10 October 2013 5Scientific Detector Workshop 2013. 7-11 October 2013. Florence, Italy

Unoptimized HV-clock step response

Optimized HV-clock step response

RTD cut on the unoptimized CCD RTD cut on the optimized CCD

Experimental Results

The oscilloscope shows that the HV-clock of the CC220 varies during the frame readout and variation is proportional to illumination level. This sensitivity to disturbances can be minimized with the proper tuning of the PID controller. Thanks to the accurate model of the transformer the value of the components in the PID have been optimized by simulation to respond quickest to disturbances.

All the simulations have been confirmed by measurements and both agree extremely well. The excellent results speak by themselves.

Spice Model of the High-Voltage Transformers for the CCD220

Thanks to Jorge Romero and the University of Malaga for this

outstanding work