Post on 16-Dec-2015
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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EVLA Front-End CDR
The New EVLA
Receiver Card Cage
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Overview
• The EVLA Card Cage shall:– Provide 8 stages of conditioned LNA bias– Control and monitor cryogenic sensors– Interface to Monitor/Control system
• (But allow stand-alone bench testing)
– Mount to EVLA receivers– Minimize EMI– Minimize assembly time and cost
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Block Diagram
FE Card Cage
Control/Sensor Card
Spare/OptionalCard Slot
DC VoltageRegulator
Board
Bac
k P
lan
eFront Panel User Interface
VacStby Cool Heat
FailL/R
LNA Bias Card
PotsLCP
VD ID
VD
VD
VD ID
ID
ID
RCP
VD ID
ID
ID
ID
VD
VD
VD
Scott-TeeXformer
DC PowerDistribution
AC RelayBox
PumpController
Module
M&C F317 Module
MIB
Dewar
LNA Over-Voltage
ProtectionBoard LCP
LNA
RCPLNA
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Pseudo-passive Scheme
• 96 available analog monitor points, selectable in banks of 3
• Default critical diagnostic parameters– Gate voltage sums (RCP, LCP)– 15K stage temperature
• MIB mounted remotely• No digital signal traffic during observation
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Card Cage:EVLA vs. VLA/VLBA
VLA/VLBA EVLA4 stages of bias/card 8 stages of bias per card
Hard-wired logic Programmable logic
Hand-wired interconnects Backplane/ribbon cable
Clock-driven display Pseudo-passive monitoring
Unique to each Rx band Universal design
AC/digital EMI No AC or fast clocks
Open, custom chassis Modified COTS enclosure
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Chassis: EVLAInterim only
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Wiring: VLA
•250-300 individual solder points•Wire directions hand- randomized to prevent EMI due to AC
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Wiring: EVLA
•6 IDC connections•8 solder points•16 crimps•No AC, clocks
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Enclosure
• COTS Stamped Al VME Chassis
• Pre-assembled with hardware
• 1/3 the weight of extruded aluminum
• 1/4 the cost!
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Minimizing Assembly
• IDC/Crimp vs. hand-soldering
• Pre-assembled chassis
• Modular, universal design
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Control/Sensor Card
• Replaces VLA:– Control,
– Sensor and
– Monitor cards
• Altera CPLD• No fast clock!• 4” x 6” Eurocard
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Control PLD
• Communication registers for Digital IO– 32 x 4 latching input registers
– 32 x 4 output registers
– SPI-compatible
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Cryogenic State Machine
• 9 sensor comparators
• 4 user-set state commands
• 14-way LED state indicator
• Local/remote control
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Cryogenic Control
-2
0
2
4
6
8
10
0:00
:00
0:10
:30
0:21
:00
0:31
:30
0:42
:00
0:52
:30
1:03
:00
1:13
:30
1:24
:00
1:34
:30
1:45
:00
1:55
:30
2:06
:00
2:16
:30
2:27
:00
2:37
:30
2:48
:00
2:58
:30
3:09
:00
3:19
:30
3:30
:00
3:40
:30
3:51
:00
4:01
:30
4:12
:00
4:22
:30
4:33
:00
4:43
:30
4:54
:00
5:04
:30
5:15
:00
5:25
:30
5:36
:00
5:46
:30
5:57
:00
6:07
:30
Time (10 second interval)
Vo
lta
ge
15K
50K
Vd
Solenoid Status
Pump Request Status
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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AC Relay Box
• Removes AC & its EMI from Card Cage
• Allows logicbypass for Fridge
• Separate LEDfor each request
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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8-Stage Bias Card
• Based on GBT 6-stage design
• Allows disabling of stages in banks of 2
• VD, ID, and VG are monitored
• 4” x 6” Eurocard
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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LNA Diode Protection Board
• Accommodates 8 bias stages
• Drain voltage clamped to +6V/-1V
• Gate voltage clamped to +1V/-2V
• Soldered to hermetic feedthrough
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Receiver ID
• Band code, Receiver S/N, and revision stored in 64kB EEPROM
• Spare capacity for text—CAL files, bias settings, etc.
• Follows receiver, not Card Cage
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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RF/IF Box Interface
• Accommodates VLA and EVLA solar calibration• 28V noise cal is not switched in Card Cage
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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RF/IF Box Interface
• SPI for logic, step attenuators• LVTTL from Card Cage to external
switching circuit• Separate voltage
regulation for Room-TempRF components
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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DC Power
• +17, -17, +7, +32V from DC distribution– Through to RF/IF interface
• +15, -15, +5, +3.3V for Card Cage, AC Relay BoxVoltage from
DC Distribution
Card Cage
RF/IF Box
AC Relay Box
Total at DC Distribution
Current (A)
Current (A)
Current (A)
Current (A)
+17 VDC 0.60 1.40 0.00 2.00
-17 VDC 0.26 0.10 0.00 0.36
+7 VDC 0.64 0.90 0.05 1.59
+32.0 VDC 0.00 0.08 0.00 0.08
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Monitor & Control
• Up to 35’ cable run Differential ( 25 STPs)– +/-5V analog range– LVDS for digital
• Monitor 3 of 96 possible analog points– Select with 5-bit address from F317– Change only when data will not be corrupted
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Production Costs
Unit cost for 30 (5 antenna/yr.) cost for 165 (entire array)
Backplane $5,263 $13,657
Daughtercard $7,042 $22,169
Bias Card $6,913 $32,386
Control/Sensor Card $9,630 $34,485
Voltage Regulator Card $2,243 $9,613
RF/IF Box Cal Switching $3,516 $13,536
Ribbon Cable Assemblies $1,897 $8,286
Chassis $8,163 $39,271
Total $44,667 $173,403
Each $1490 $1050
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Summary
• Eliminates EMI from fast clocks/AC
• Universal to all receivers
• Minimizes assembly time & cost
• Leverages existing NRAO designs (where possible)
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Effect of Bias Card on Receiver Performance
C Band #05 LCP Trx Including warm test polarizerOld vs New card cage
10
12
14
16
18
20
22
4.5 4.6 4.7 4.8 4.9 5 5.1 5.2
Frequency (GHz)
Trx
(K
)
LCP New
LCP Old
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Effect of Bias Card on Receiver Performance
C Band #05 RCP Trx Including warm test polarizerOld vs New Card cage
10
12
14
16
18
20
22
4.5 4.6 4.7 4.8 4.9 5 5.1 5.2
Frequency (GHz)
Trx
(K
)
RCP New
RCP Old
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Monitor and Control
VD1VD2VD3VD4VD5VD6VD7VD8
ID1ID2ID3ID4ID5ID6ID7ID8
VG1VG2VG3VG4VG5VG6VG7VG8
A[4..0]
Temp 15KTemp 50KDewar VacuumPump VacuumPower Supply MonitorNoise Cal Mon2nd Bias MonitorSpare Monitor
BiasMonitor
SensorMonitor
AnalogMonitorto F317
3
Analog Multiplexers
Keith Morris EVLA Front-End CDR – New EVLA Receiver Card CageApril 24, 2006
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Monitor & Control: Digital Monitors