ADF7020BCPZ Analog Devices Inc, ADF7020BCPZ Datasheet - Page 18

• Manufacturer Part Number: ADF7020BCPZ
• Description: IC TX FSK/ASK ISM BAND 48LFCSP
• Manufacturer: Analog Devices Inc

Specifications of ADF7020BCPZ

• 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: 19mA
• Current - Transmitting: 26.8mA @ 10dBm
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-LFCSP
• Data Rate: 200Kbps
• Supply Voltage Range: 2.3V To 3.6V
• Logic Case Style: LFCSP
• No. Of Pins: 48
• Operating Temperature Range: -40°C To +85°C
• Msl: MSL 1 - Unlimited
• Termination Type: SMD
• 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-ADF7020DBZ3 - BOARD EVAL ADF7020 433-445MHZEVAL-ADF7020DBZ2 - BOARD EVAL ADF7020 862-870MHZEVAL-ADF7020DBZ1 - BOARD EVAL ADF7020 902-928MHZ
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant

ADF7020
TRANSMITTER
RF OUTPUT STAGE
The PA of the ADF7020 is based on a single-ended, controlled
current, open-drain amplifier that has been designed to deliver
up to 13 dBm into a 50 Ω load at a maximum frequency of
956 MHz.
The PA output current and, consequently, the output power are
programmable over a wide range. The PA configurations in
FSK/GFSK and ASK/OOK modulation modes are shown in
Figure 25 and Figure 26, respectively. In FSK/GFSK modulation
mode, the output power is independent of the state of the
DATA I/O pin. In ASK/OOK modulation mode, it is dependent
on the state of the DATA I/O pin and Bit R2_DB29, which
selects the polarity of the TxData input. For each transmission
mode, the output power can be adjusted as follows:
•
•
•
DATA I/O
RFGND
RFOUT
RFGND
RFOUT
FSK/GFSK
The output power is set using Bits R2_DB[9:14].
ASK
The output power for the inactive state of the TxData input
is set by Bits R2_DB[15:20]. The output power for the
active state of the TxData input is set by Bits R2_DB[9:14].
OOK
The output power for the active state of the TxData input
is set by Bits R2_DB[9:14]. The PA is muted when the TxData
input is inactive.
FROM VCO
FROM VCO
Figure 25. PA Configuration in FSK/GFSK Mode
Figure 26. PA Configuration in ASK/OOK Mode
R2_DB29
+
+
R2_DB[30:31]
R2_DB[30:31]
IDAC
IDAC
6
2
ASK/OOK MODE
6
6
6
0
R2_DB[9:14]
R2_DB4
R2_DB5
DIGITAL
LOCK DETECT
R2_DB[9:14]
R2_DB[15:23]
R2_DB4
R2_DB5
DIGITAL
LOCK DETECT
Rev. B | Page 18 of 48
The PA is equipped with overvoltage protection, which makes it
robust in severe mismatch conditions. Depending on the applica-
tion, one can design a matching network for the PA to exhibit
optimum efficiency at the desired radiated output power level
for a wide range of different antennas, such as loop or mono-
pole antennas. See the LNA/PA Matching section for details.
PA Bias Currents
Control Bits R2_DB[30:31] facilitate an adjustment of the PA
bias current to further extend the output power control range,
if necessary. If this feature is not required, the default value of
7 μA is recommended. The output stage is powered down by
resetting Bit R2_DB4. To reduce the level of undesired spurious
emissions, the PA can be muted during the PLL lock phase by
toggling this bit.
MODULATION SCHEMES
Frequency Shift Keying (FSK)
Frequency shift keying is implemented by setting the N value
for the center frequency and then toggling this with the TxData
line. The deviation from the center frequency is set using
Bits R2_DB[15:23]. The deviation from the center frequency
in Hz is
where Modulation Number is a number from 1 to 511
(R2_DB[15:23]).
Select FSK using Bits R2_DB[6:8].
FSK DEVIATION
TxDATA
FREQUENCY
+
–
f
f
FSK
DEV
DEV
DEVIATION
4R
[
CHARGE
Hz
FRACTIONAL-N
Figure 27. FSK Implementation
PUMP
PFD/
]
=
PFD
Σ-Δ MODULATOR
×
THIRD-ORDER
Modulation
2
14
INTEGER-N
Number
VCO
÷N
PA STAGE