Generic Digitizer 10MHZ 16 bit 6U VME Board

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Generic Digitizer 10MHZ 16 bit6U VME Board
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Futures

• 12 channels, 16 bit at 6U VME Board
• DC- up to 10MSPS Operation
• Up to 500k sample per channel buffer
• Hardware Software onboard data processing
• Smart triggering based on FPGA algorithm

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Generic Digitizer
10MHz,16bit 3 channels ADC 4 CHIPS
VME BUS
FPGA CYCLONE EP1C12240 State
Machine Logic OR/AND NIOS Embedded Processor
A n a l o g I n p u t s
VME Drivers
4Mx32 SDRAM MT48LC4M32B2
JTAG
4 Mbit Serial Configuration Device EPCS4
EPCS4 Interface MAX7128
CLOCK IN
4 Mbit Serial FLASH Device EPCS4
CLOCK OUT
GATE
External Control
TRIGGER
TCLK
SYNC IN
SYNC OUT
CRYSTAL 25MHz
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Digitizer Prototype
LED s Ready, VME, Gate, Trigger
EXT Clock
EXT Gate
EXT Trigger
SYNC
TCLK
VME DRIVER s
HW Reset
PreAMP s
JTAG
ADC s
FPGA
SDRAM
12 analog inputs
25MHz Crystal
Mode Select SW
Configuration Device
HW Address
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AD9826 16-Bit Signal Processor

• Features
• 16-Bit 15 MSPS A/D Converter
• 3-Channel 16-Bit Operation up to 15 MSPS
• 1-Channel 16-Bit Operation up to 12.5 MSPS
• Correlated Double Sampling
• 16x Programmable Gain
• 300 mV Programmable Offset
• Input Clamp Circuitry
• Internal Voltage Reference
• Multiplexed Byte-Wide Output
• Optional Single Byte Output Mode
• 3-Wire Serial Digital Interface

The AD9826 is a complete analog signal
processor. It features a 3-channel architecture
designed to sample and condition the outputs of
color CCD arrays. Each channel consists of an
input clamp, Correlated Double Sampler (CDS),
offset DAC, and Programmable Gain Amplifier
(PGA), multiplexed to a high-performance 16-bit
A/D converter.
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FPGA Design
3 channels x 4 12channels
Data from ADC
ADC Data Channels MUX
FIFO 512x16
Data MUX
Local BUS Arbiter MUX
SDRAM Interface
SDRAM
FIFO 512x16
FIFO 512x16
Set ADC Mode, Gain, Offset
VME interface
VME BUS
ADC Serial Control interface
Digitizer MODE Control
TCLK
Serial configuration Device Interface
Gate
Trigger
Sync
ADC CLOCK
To EPCS4 Interface
PLL Multiplier
INT CLOCK 25MHz
RF,53MHz
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LabView Interface
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STILL OPEN QUESTIONS

• Channel to channel crosstalk is 80dB at 10MHz
  from specification for AD9826. What is this
  ratio for a real board? And also,
• What is a total ADC noise (3-9 LSB from spec)
  ?
• What is a Integral and Differential Nonlinearity
  (16 and 0.5 LSB from spec)?