Document type:
Title:
Revision date:
Revision:
User's Manual (MUT)
Mod. DT5740 32 Channel 12bit - 65MS/s Digitizer
04/05/2016
12
NPO:
Filename:
Number of pages:
Page:
00100/09:5740x.MUTx/12
DT5740_REV12.DOC
50
19
3.2
Clock Distribution
M
U
X
OSC
CLK-IN
50MHz
REF-CLK
Trigger & Sync
Logic
TRG IN
Local Bus
Interface
Acquisition
& Memory
Control
Logic
MEZZANINE
TRIGGER
SYNC
LOCAL-TRGs
M
U
X
Phase
Detector
AD9520
CLK1
Sdiv
Sdiv
Rdiv
REFIN
Charge
Pump
INTCLK
CTRL
SPI
Ldiv
Odiv
Ndiv
SAMP-CLK0
FPGA (AMC)
ADC
SYNC
SRAM
256Klocations
FIFO
ADC
CH_IN
Ldel
Odel
Local Bus
Interface
FPGA (ROC)
SYNCB
TRG-CLK
SyncB
OSC-CLK
8
DFF
ADC
ADC
SCLK
DATA/CLKOUT
FANOUT
SCLK
SCLK
SCLK
DATA/CLKOUT
DATA/CLKOUT
DATA/CLKOUT
8CH
8CH
8CH
8CH
Local Bus
Interface
Acquisition
& Memory
Control
Logic
FPGA (AMC)
SYNC
SRAM
256Klocations
FIFO
RAMCLK
DATA
144BIT
DATA
144BIT
RAMCLK
L
O
C
A
L
B
U
S
M
U
X
Phase
Detector
CLK1
Sdiv
Rdiv
REFIN
INTCLK
CTRL
Ldiv
Odiv
Ndiv
Ldel
Odel
SYNCB
VCXO
Fig. 3.2: Clock distribution diagram
The module clock distribution takes place on two domains: OSC-CLK and REF-CLK; the former is a
fixed 50MHz clock provided by an on board oscillator, the latter provides the ADC sampling clock.
OSC-CLK handles Local Bus (communication between motherboard and mezzanine boards; see
red traces in Fig. 3.2).
REF-CLK handles ADC sampling, trigger logic, acquisition logic (samples storage into RAM, buffer
freezing on trigger) through a clock chain. Such domain can use either an external (via front
panel signal) or an internal (via local oscillator) source, in the latter case OSC-CLK and REF-CLK
will be synchronous (the operation mode remains the same anyway).
DT5740 uses an integrated phase-locked-loop (PLL) and clock distribution device (AD9520). It is
used to generate the sampling clock for ADCs and mezzanine FPGA (SAMP-CLK0/SAMP-CLK1), as
well as the trigger logic synchronization clock (TRG-CLK).