HI5728EVAL1 Intersil, HI5728EVAL1 Datasheet - Page 5

• Manufacturer Part Number: HI5728EVAL1
• Description: EVALUATION PLATFORM TQFPHI5728
• Manufacturer: Intersil

Specifications of HI5728EVAL1

• Number Of Dac's: 2
• Number Of Bits: 10
• Outputs And Type: 2, Differential
• Sampling Rate (per Second): 125M
• Data Interface: Parallel
• Settling Time: 35ns
• Dac Type: Current
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: HI5728
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Appendix A Description of Architecture
The segmented current source architecture has the ability to
improve the converter’s performance by reducing the
amount of current that is switching at any one time. In
traditional architectures, major transition points required the
converter to switch on or off large amounts of current. In a
traditional 10-bit R/2R ladder design, for example, the
midscale transition required approximately equal amounts of
currents switching on and off. In a segmented current source
arrangement, transitions such as midscale become one in
which you simply have an additional intermediate current
source turning on and several minor ones turning off. In the
case of the HI5728, there are 31 intermediate current
segments that represent the 5 MSBs and five, binary-
PERSONAL COMPUTER
WITH HSP-EVAL
SOFTWARE
INCLUDED
CIRCUIT
CLOCK
FIGURE 2. INTERSIL HI5728/DDS EVALUATION SYSTEM SETUP BLOCK DIAGRAM
3-5
NCOM EVALUATION BOARD
OR A DATA GENERATOR
HSP-EVAL/HSP45116
HSP-EVAL/HSP45116DB
PC INTERFACE
NUMERICALLY
CONTROLLED
OSCILLATOR
EVAL KIT
Application Note 9827
10 BITS
10 BITS
SUPPLY
POWER
+5V
weighted current sources representing each of the five
LSBs. See the Functional Block Diagram in the data sheet
for a visual representation. To relate the midscale transition
example to the HI5728, consider the following: The code
0111111111 would be represented by 15 intermediate
current segments and each of the 5 LSB current sources all
turned on. To transition to code 1000000000 would simply
require turning off the 5 LSB current sources and turning on
the next intermediate current segment, bringing the total
amount of current switching at this ‘major’ code transition
equal to the same amount switching at 30 other code
transition points in the code ramp from 0 to 1023, so that the
total glitch energy is distributed more evenly.
DAC MODULE
HI5728EVAL1
Q Channel
I Channel
SUPPLY
POWER
HI5728
+5V
SPECTRUM ANALYZER
CABLE
SMA
50