AD9851BRS Analog Devices Inc, AD9851BRS Datasheet - Page 10
AD9851BRS
Manufacturer Part Number
AD9851BRS
Description
Direct Digital Synthesizer 180MHz 1-DAC 10-Bit Parallel/Serial 28-Pin SSOP
Manufacturer
Analog Devices Inc
Datasheet
1.AD9851BRSZ.pdf
(24 pages)
Specifications of AD9851BRS
Resolution
10 Bit
Maximum Input Frequency
180 MHz
Tuning Word Width
32 Bit
Minimum Operating Supply Voltage
2.7 V
Typical Operating Supply Voltage
5 V
Maximum Operating Supply Voltage
5.25 V
Minimum Operating Temperature
-40 °C
Maximum Operating Temperature
85 °C
Rohs Status
RoHS non-compliant
Resolution (bits)
10 b
Master Fclk
180MHz
Tuning Word Width (bits)
32 b
Voltage - Supply
2.7 V ~ 5.25 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
28-SSOP
For Use With
AD9951/PCBZ - BOARD EVALUATION FOR AD9851
Lead Free Status / RoHS Status
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
AD9851BRS
Manufacturer:
ADI/亚德诺
Quantity:
20 000
Company:
Part Number:
AD9851BRSZ
Manufacturer:
ADI41
Quantity:
377
IOUT and IOUTB are equally loaded with 100 . Two 100 k
resistors sample each output and average the two voltages. The
result is filtered with the 470 pF capacitor and applied to one
comparator input as a dc switching threshold. The filtered DAC
sine wave output is applied to the other comparator input. The
comparator will toggle with nearly 50% duty cycle as the sine
wave alternately traverses the center point threshold.
AD9851
IF FREQUENCY
REFERENCE
Figure 4. Frequency/Phase-Agile Reference for PLL
Figure 3. Frequency/Phase-Agile Local Oscillator
for Frequency Mixing/Multiplying
CLOCK
REFERENCE
MICROCONTROLLER
CLOCK
MICROPROCESSOR
IN
180MHz OR 30MHz
REFERENCE
COMPARATOR
OR
DIVIDE-BY-N
CLOCK
AD9851
FILTER
PHASE
DDS
AD9851
FILTER
RF IN
Figure 1. Chip Rate Clock Generator Application in a Spread Spectrum Receiver
DDS
Rx
DATA
BUS
VCA
FILTER
TUNING
WORD
LOOP
3.9k
8-BIT PARALLEL DATA,
OR 1-BIT 40 SERIAL DATA,
RESET, W CLK AND FQ UD
FILTER
TUNING
WORD
R
SET
Tx CHIP/SYMBOL/PN RATE
VCO
ADC CLOCK FREQUENCY
AD9851
REFERENCE
LOW-PASS
OR 30MHz
Figure 2. Basic Clock Generator Configuration
I/Q MIXER
180MHz
FILTER
CLOCK
QOUT
AND
OUTPUTS
CMOS
RF
FREQUENCY
OUT
LOCKED TO
RF
FREQUENCY
OUT
QOUTB
Q
I
IOUTB
IOUT
GENERATOR
8-BIT ADC
AD9851
AD9059
CLOCK
DUAL
ADC ENCODE
–10–
470pF
High quality, all digital RF frequency modulation generation with
the ADSP-2181 DSP and the AD9851 DDS is well documented
in Analog Devices’ application note AN-543. It uses an image of
the DDS output as illustrated in Figure 8.
AUDIO IN
CHIP/SYMBOL/PN
L & R
8
8
100k
100k
100
REFERENCE
RATE DATA
CLOCK
Figure 5. Digitally Programmable Divide-by-N
Function in PLL
Figure 6. High Quality, All Digital RF Frequency
Modulation
32
EZ-KIT LITE
PROCESSOR
FILTER
DEMODULATOR
ADSP-2181
STEREO
AD1847
CODEC
DIGITAL
VOLTAGE HERE = CENTER POINT
OF SINE WAVE (0.5V TYPICALLY)
USING PASSIVE AVERAGING CIRCUIT
DSP
DSP
200
7TH ORDER ELLIPTICAL
COMPARATOR
70MHz LOW PASS
200 IMPEDANCE
AGC
AD9851
TUNING
PHASE
WORD
LOW-PASS
DDS
ADSP-2181
BUS
FILTER
DECODE
OUTPUT
Rx BASEBAND
DIGITAL DATA OUT
INPUT/
LOGIC
REF CLK IN
FILTER
(WHERE N = 2
DATA
LOOP
8-BIT
BUS
DIVIDE-BY-N FUNCTION
200
PROGRAMMABLE
AD9851/FSPCB
EVALUATION
AD9851
VCO
DDS
BOARD
32
/ TUNING WORD)
0 TO 1V p-p
SINE WAVE
REF
OSC
DAC
OUT
RF
FREQUENCY
OUT
FM RF
OUTPUT
REV. D