ADC08D1020DEV/NOPB National Semiconductor, ADC08D1020DEV/NOPB Datasheet - Page 4

• Manufacturer Part Number: ADC08D1020DEV/NOPB
• Description: BOARD DEV FOR ADC08D1020
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of ADC08D1020DEV/NOPB

• Number Of Adc's: 2
• Number Of Bits: 8
• Sampling Rate (per Second): 1G
• Data Interface: Serial
• Inputs Per Adc: 1 Differential
• Input Range: 870 mVpp
• Power (typ) @ Conditions: 1.6W @ 1GSPS
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: ADC08D1020
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ADC08D1020DEV

The following supplies are provided by on board
regulators (Switching and Linear):
A power LED indicator is provided on the front edge of
the board along with the status LEDs.
A Rocker Switch is provided on the rear edge of the
board to allow easy cold start/re-start.
Figure 1 shows the power supplies required for the
design in more detail.
The USB Microcontroller controls the shutdown pins of
all the switching regulators to minimize power in standby
mode.
3.5 Clocking
The USB Microcontroller is clocked by its own 24 MHz
crystal oscillator.
The ADC is clocked by either a National Semiconductor
PLL and a VCO device, or an external clock source.
Switching between clock sources is done through a relay
controlled by the WaveVision software.
The PLL and VCO devices are selected to provide a 500
MHz, 1000 MHz or 1500 MHz very low jitter on-board
clock depending on which ADC is used.
3.3V - USB Microcontroller
3.3V – FPGA (LVCMOS I/O)
2.5V - FPGA (AUX Supply and LVDS25 I/O)
1.9V - ADC (V
1.2V – FPGA (CORE)
A
and V
DR
)
Figure 1. Power supply architecture
The on-board PLL is programmed over a serial interface
through the FPGA.
The FPGA may be clocked by one of two sources:
3.6 Resets
The USB Microcontroller utilizes a simple RC power-on-
reset circuit along with local push-button reset. The
FPGA has a RESET input signal which is controlled by
the USB Microcontroller.
3.7 Thermal Management
The ADC and the Virtex 4 FPGA temperature diodes are
connected to a National Semiconductor LM95221 Dual
Temperature Sensor device. This temp sensor interfaces
to the USB Microcontroller over a 2 wire serial bus. The
ADC’s temperature is monitored to determine when
calibration cycles are required.
initiate a calibration cycle using the WaveVision software.
1. When capturing data from the ADC, the FPGA is
2. When calculating the input clock frequency and
clocked from the source synchronous ADC
clock, which will operate at a rate of either Fs/2
(Single Data Rate) or Fs/4 (Dual Data Rate).
uploading the captured data to the USB
Microcontroller, an on-board crystal oscillator
running at 100 MHz is used.
The user may also
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