Datasheet

www.ti.com
f − Frequency − MHz
−130
−120
−110
−100
−90
−80
−70
−60
−50
−40
−30
−20
133 138 143 148 153 158 163 168 173
P − Power − dBm
G025
f
data
= 122.88 MSPS
IF = 153.6 MHz
y4 Interpolation
CMIX
Carrier Power 1 (Ref): −19.88 dBm
ACLR (5 MHz): 66.6 dB
ACLR (10 MHz): 65.73 dB
Test Methodology
DAC5687
SLWS164E FEBRUARY 2005 REVISED SEPTEMBER 2006
Typical Characteristics (continued)
Figure 25. WCDMA TM1: Four Carriers, PLL Off,
DVDD = 2.1 V
Typical ac specifications in external clock mode were characterized with the DAC5687EVM using the test
configuration shown in Figure 26 . The DAC sample-rate clock f
DAC
is generated by an HP8665B signal
generator. An Agilent 8133A pulse generator is used to divide f
DAC
for the data-rate clock f
DATA
for the Agilent
16702A pattern-generator clock and provide adjustable skew to the DAC input clock. The 8133A f
DAC
output is
set to 1 V
PP
, equivalent to 2-V
PP
differential at CLK2/CLK2C pins. Alternatively, the DAC5687 PLLLOCK output
can be used for the pattern generator clock.
The DAC5687 output is characterized with a Rohde & Schwarz FSQ8 spectrum analyzer. For WCDMA signal
characterization, it is important to use a spectrum analyzer with high IP3 and noise subtraction capability so that
the spectrum analyzer does not limit the ACPR measurement. For all specifications, both DACA and DACB are
measured and the lowest value used as the specification.
Copyright © 2005 2006, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Link(s): DAC5687