ADF7020-1BCPZ-RL7 Analog Devices Inc, ADF7020-1BCPZ-RL7 Datasheet - Page 17

• Manufacturer Part Number: ADF7020-1BCPZ-RL7
• Description: IC,RF Modulator/Demodulator,LLCC,48PIN,PLASTIC
• Manufacturer: Analog Devices Inc

Specifications of ADF7020-1BCPZ-RL7

• Design Resources: Low power, Long Range, ISM Wireless Measuring Node (CN0164)
• Frequency: 431MHz ~ 478MHz and 862MHz ~ 956MHz
• Data Rate - Maximum: 200kbps
• Modulation Or Protocol: ASK, FSK
• Applications: Data Transfer, RKE, Remote Control/Security Systems
• Power - Output: -16dBm ~ 13dBm
• Sensitivity: -119dBm
• Voltage - Supply: 2.3 V ~ 3.6 V
• Current - Receiving: 17.6mA
• Current - Transmitting: 21mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-LFCSP
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 7mm
• Product Length (mm): 7mm
• Operating Supply Voltage (min): 2.3V
• Operating Supply Voltage (typ): 2.5/3.3V
• Operating Supply Voltage (max): 3.6V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-ADF7020-1DBZ8 - BOARD EVAL ADF7020-1 128-142MHZEVAL-ADF7020-1DBZ7 - BOARD EVAL ADF7020-1 310-340MHZEVAL-ADF7020-1DBZ6 - BOARD EVAL ADF7020-1 470-510MHZEVAL-ADF7020-1DBZ4 - BOARD EVAL ADF7020-1 405-435MHZEVAL-ADF7020-1DBZ5 - BOARD EVAL ADF7020-2 ADJ FREQ
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant

The VCO can be recentered, depending on the required
frequency of operation, by programming the VCO adjust bits
R1_DB (20:21).
The VCO is enabled as part of the PLL by the PLL-enable bit,
R0_DB28.
The VCO needs an external 22 nF between the VCO and the
regulator to reduce internal noise.
VCO Bias Current
VCO bias current can be adjusted using Bits R1_DB19 to
R1_DB16. To minimize current consumption, the bias current
setting should be as indicated in Table 5.
Table 5. Recommended VCO Bias Currents
Direct Frequency Output (f)
f < 200 MHz
200 MHz < f < 450 MHz
f > 450 MHz
LOOP FILTER
R1_DB (16:19)
VCO BIAS
650
600
550
500
450
400
350
300
250
200
750
700
CVCO PIN
0
220μF
Figure 25. Voltage Controlled Oscillator (VCO)
Figure 24. External Inductance vs. Frequency
VCO
F
5
MIN
TOTAL EXTERNAL INDUCTANCE (nH)
F
(MHz)
MAX
÷2
(MHz)
10
DIVIDER
TO N
15
VCO Bias R1_DB(19:16)
0001
0010
0011
VCO SELECT BIT
÷2
20
MUX
25
TO PA
30
Rev. 0 | Page 17 of 48
CHOOSING CHANNELS FOR BEST SYSTEM
PERFORMANCE
The fractional-N PLL allows the selection of any channel within
80 MHz to 650 MHz to a resolution of <300 Hz. This also
facilitates frequency-hopping systems.
Careful selection of the RF transmit channels must be made
to achieve best spurious performance. The architecture of
fractional-N results in some level of the nearest integer channel
moving through the loop to the RF output. These beat-note
spurs are not attenuated by the loop if the desired RF channel
and the nearest integer channel are separated by a frequency of
less than the LBW.
The occurrence of beat-note spurs is rare, because the integer
frequencies are at multiples of the reference, which is typically
>10 MHz.
The amplitude of beat-note spurs can be significantly reduced
by using the frequency doubler to avoid very small or very large
values in the fractional register. By having a channel 1 MHz
away from an integer frequency, a 100 kHz loop filter can
reduce the level to <−45 dBc.
ADF7020-1