1Sasha Milov HBD internal... July 10, 2007

New divider floating vs. New divider floating vs. groundedgrounded

Sasha Milov

July 10, 2007

2Sasha Milov HBD internal... July 10, 2007

New dividerNew divider

Some other changes:

a) GEMS are not shown because they are made of 28 R/C and are huge.

b) No change in the results compare to the old scheme found

c) In the scheme on the left PS shorts to zero at a trip time. I used 1ms fall time and 1Meg residual resistance on the PS Rout.

d) Changing Rout to zero does not really change much, anyways.

R10

{R1}

R11

{R3}

R12

{R2}

R13

{R4}

R1

{R3}

R2

{R1}

R3

{R2}

R4

{R4}

R6

{R3}

R7

{R2}

R8

{R1}

R9

{R4}

R16

{R4}

PULSE({VG} 0 .1 0.001 0 10 100)Rser=1e6

GEM_PS

Rser=1e6

MESH_PS

PULSE({VM} 0 0.1 0.001 0 10 100)

bg1

{C8}

R18

{R5}

Cable_CG

{C4}

Cable_LG

{L0}

Cable_RG

{R9}

Cable_CM

{C4}

Cable_LM

{L0}

Cable_RM

{R9}

R19

{R6}

D1

DFLZ33

D2

DFLZ33

bg2

{C8}

R5

{R5}

bg3

{C8}

R14

{R5}

bg4

{C8}

R15

{R5}

bg5

{C8}

R17

{R5}

bg6

{C8}

R21

{R5}

bg7

{C8}

R23

{R5}

bg8

{C8}

R24

{R5}

bg9

{C8}

R25

{R5}

bg10

{C8}

R26

{R5}

bg11

{C8}

R27

{R5}

bg12

{C8}

R28

{R5}

bg13

{C8}

R29

{R5}

bg14

{C8}

R30

{R5}

bg15

{C8}

R31

{R5}

bg16

{C8}

R32

{R5}

bg17

{C8}

R33

{R5}

bg18

{C8}

R34

{R5}

bg19

{C8}

R35

{R5}

bg20

{C8}

R36

{R5}

bg21

{C8}

R37

{R5}

bg22

{C8}

R38

{R5}

bg23

{C8}

R39

{R5}

bg24

{C8}

R40

{R5}

bg25

{C8}

R41

{R5}

bg26

{C8}

R42

{R5}

bg27

{C8}

R43

{R5}

bg28

{C8}

R44

{R5}

bg85

{C9}

bg86

{C9}

bg87

{C9}

bg88

{C9}

bg89

{C9}

bg90

{C9}

bg91

{C9}

bg92

{C9}

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{C9}

bg94

{C9}

bg95

{C9}

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{C9}

bg97

{C9}

bg98

{C9}

bg99

{C9}

bg100

{C9}

bg101

{C9}

bg102

{C9}

bg103

{C9}

bg104

{C9}

bg105

{C9}

bg106

{C9}

bg107

{C9}

bg108

{C9}

bg109

{C9}

bg110

{C9}

bg111

{C9}

bg29

{C8}

R20

{R5}

bg30

{C8}

R22

{R5}

bg31

{C8}

R45

{R5}

bg32

{C8}

R46

{R5}

bg33

{C8}

R47

{R5}

bg34

{C8}

R48

{R5}

bg35

{C8}

R49

{R5}

bg36

{C8}

R50

{R5}

bg37

{C8}

R51

{R5}

bg38

{C8}

R52

{R5}

bg39

{C8}

R53

{R5}

bg40

{C8}

R54

{R5}

bg41

{C8}

R55

{R5}

bg42

{C8}

R56

{R5}

bg43

{C8}

R57

{R5}

bg44

{C8}

R58

{R5}

bg45

{C8}

R59

{R5}

bg46

{C8}

R60

{R5}

bg47

{C8}

R61

{R5}

bg48

{C8}

R62

{R5}

bg49

{C8}

R63

{R5}

bg50

{C8}

R64

{R5}

bg51

{C8}

R65

{R5}

bg52

{C8}

R66

{R5}

bg53

{C8}

R67

{R5}

bg54

{C8}

R68

{R5}

bg55

{C8}

R69

{R5}

bg56

{C8}

R70

{R5}

bg57

{C9}

bg58

{C9}

bg59

{C9}

bg60

{C9}

bg61

{C9}

bg62

{C9}

bg63

{C9}

bg64

{C9}

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{C9}

bg66

{C9}

bg67

{C9}

bg68

{C9}

bg69

{C9}

bg70

{C9}

bg71

{C9}

bg72

{C9}

bg73

{C9}

bg74

{C9}

bg75

{C9}

bg76

{C9}

bg77

{C9}

bg78

{C9}

bg79

{C9}

bg80

{C9}

bg81

{C9}

bg82

{C9}

bg83

{C9}

bg84

{C8}

R71

{R5}

bg112

{C8}

R72

{R5}

bg113

{C8}

R73

{R5}

bg114

{C8}

R74

{R5}

bg115

{C8}

R75

{R5}

bg116

{C8}

R76

{R5}

bg117

{C8}

R77

{R5}

bg118

{C8}

R78

{R5}

bg119

{C8}

R79

{R5}

bg120

{C8}

R80

{R5}

bg121

{C8}

R81

{R5}

bg122

{C8}

R82

{R5}

bg123

{C8}

R83

{R5}

bg124

{C8}

R84

{R5}

bg125

{C8}

R85

{R5}

bg126

{C8}

R86

{R5}

bg127

{C8}

R87

{R5}

bg128

{C8}

R88

{R5}

bg129

{C8}

R89

{R5}

bg130

{C8}

R90

{R5}

bg131

{C8}

R91

{R5}

bg132

{C8}

R92

{R5}

bg133

{C8}

R93

{R5}

bg134

{C8}

R94

{R5}

bg135

{C8}

R95

{R5}

bg136

{C8}

R96

{R5}

bg137

{C8}

R97

{R5}

bg138

{C8}

R98

{R5}

bg139

{C9}

bg140

{C9}

bg141

{C9}

bg142

{C9}

bg143

{C9}

bg144

{C9}

bg145

{C9}

bg146

{C9}

bg147

{C9}

bg148

{C9}

bg149

{C9}

bg150

{C9}

bg151

{C9}

bg152

{C9}

bg153

{C9}

bg154

{C9}

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{C9}

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{C9}

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{C9}

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{C9}

bg159

{C9}

bg160

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bg162

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{C9}

bg164

{C9}

bg165

{C9}

.param R1 = 20e6

.param R2 = 10e6

.param R3 = 40e6

.param R4 = 2e6

.param R5 = 20e6

.param R6 = 40e6

.tran 0 3 0 .001

.param C2 = 0.335e-9

.param C4 = 0.8e-9

.param C5 = 35.e-9

.param C8 = 1.25e-9

.param C9 = 0.013e-9

.model SWO SW(Ron=1e-3 Roff=1e11 Vt=0.5)

.model SWC SW(Ron=1e11 Roff=1e-3 Vt=0.5)

.param L0 = 2e-6

.param VG = -350

.param VM = -360

.param R9 = 1Bot

Mid

Top

Mesh

3Sasha Milov HBD internal... July 10, 2007

Float vs GroundFloat vs Ground

0.0s 0.3s 0.6s 0.9s 1.2s 1.5s 1.8s 2.1s 2.4s 2.7s 3.0s-50V-40V-30V-20V-10V0V

10V20V30V40V50V60V70V80V90V

100V

4V8V

12V16V20V24V28V32V36V40V44V48V52V

-24V

-18V

-12V

-6V

0V

6V

12V

18V

24V

30V

36V

42V

V(N001,N007) V(N005,N015) V(N006,N002)

V(N002,N001) V(N007,N005) V(N015,N012)

V(N017,N012)

topGEM-mesh

across GEMs

across transfer gaps

float ground

0.0s 0.3s 0.6s 0.9s 1.2s 1.5s 1.8s 2.1s 2.4s 2.7s 3.0s-100V

-80V

-60V

-40V

-20V

0V

20V

40V

60V

80V

100V

0V

5V

10V

15V

20V

25V

30V

35V

40V

45V

50V

-10V

-8V

-6V

-4V

-2V

0V

2V

4V

6V

8V

10V

12V

V(N094,N011) V(N012,N009) V(N010,N007)

V(N011,N012) V(N009,N010) V(N007,N008)

V(N014,N008)

4Sasha Milov HBD internal... July 10, 2007

Float vs GroundFloat vs GroundGround scheme has advantages:

a)transients dV are smaller (even with Rout = 0 they are so)b)GEM discharges fasterc)Transfer gaps flip sign “momentarily” so to prevent any affect on lower GEM.

Here is my understanding of Floating vs. Grounded PS:In case of a trip one would like to drain energy form the divider. Regardless of the PS, the scheme must have such drainage system with matching R/C’s. We learned it a hard way. Floating PS leaves transient process fully at hands of that drainage system. Grounded PS provides one more sewer, which if all R/C match properly gives another factor in speed, thus safety.

Bob and me measured BERTAN yesterday found it floating with Rout = 150M (guess at Fluke’s limit…)

5Sasha Milov HBD internal... July 10, 2007

0.0s 0.3s 0.6s 0.9s 1.2s 1.5s 1.8s 2.1s 2.4s 2.7s 3.0s-40V-30V-20V-10V0V

10V20V30V40V50V60V70V80V90V

100V

4V8V

12V16V20V

24V28V32V

36V40V44V

48V52V

-28V

-24V

-20V

-16V

-12V

-8V

-4V

0V

4V

8V

12V

16V

V(N001,N003) V(N002,N008) V(N007,N016)

V(N016,N014) V(N008,N007) V(N003,N002)

V(N020,N014)

New vs Old dividersNew vs Old dividers

0.0s 0.3s 0.6s 0.9s 1.2s 1.5s 1.8s 2.1s 2.4s 2.7s 3.0s-50V-40V-30V-20V-10V0V

10V20V30V40V50V60V70V80V90V

100V

4V8V

12V16V20V24V28V32V36V40V44V48V52V

-24V

-18V

-12V

-6V

0V

6V

12V

18V

24V

30V

36V

42V

V(N001,N007) V(N005,N015) V(N006,N002)

V(N002,N001) V(N007,N005) V(N015,N012)

V(N017,N012)

topGEM-mesh

across GEMs

across transfer gaps

new (float)

old

(used)