adl5571acpz-r7 Analog Devices, Inc., adl5571acpz-r7 Datasheet - Page 11

• Manufacturer Part Number: adl5571acpz-r7
• Description: 2.5 Ghz To 2.7 Ghz Wimax Power Amplifier
• Manufacturer: Analog Devices, Inc.

APPLICATIONS INFORMATION
BASIC CONNECTIONS
Figure 19 shows the basic connections for the ADL5571.
RFIN
NC = NO CONNECT
Power Supply
The voltage supply on the ADL5571, which ranges from
3.2 V to 4.2 V, should be connected to the VCCx pins. VCC1 is
decoupled with Capacitor C7, whereas VCC2 uses a tank circuit
to prevent RF signals from propagating on the dc lines.
RF Input Interface
The RFIN pin is the port for the RF input signal to the power
amplifier. The L3 inductor, 2.7 nH, matches the input
impedance to 50 Ω.
VREG
0.01µF
C7
2.7nH
0.01µF
L3
VPOS
C9
Figure 20. RF Input with Matching Component
0.01µF
5
6
7
8
2.2pF
C8
VCC1
RFIN
GND
VREG
C2
STBY
Figure 19. Basic Connections
ADL5571
1nH
L1
C10
0.01µF
2.7nH
L3
VPOS
RFOUT
RFOUT
VPOS1
C6
3.3pF
NC
NC
6
16
15
14
13
RFIN
C11
1µF
W1
2.7pF
11nH
C3
L2
VPOS1
39pF
C4
C5
OPEN
VPOS
RFOUT
Rev. 0 | Page 11 of 16
C12
1µF
RF Output Interface
The parallel RF output ports have a shunt capacitor, C3 (2.7 pF),
and the line inductance of the microstrip line for optimized
output power and linearity. The characteristics of the ADL5571
are described for 50 Ω impedance after the output matching
capacitor (load after C3). C4 provides dc blocking on the
RF output.
Transmit/Standby Enable
During normal transmit mode, the STBY pin is biased low
(0 V). However, during receive mode, the pin can be biased
high (2.5 V) to shift the device into standby mode, which
reduces current consumption to 9 mA.
VREG Enable
During normal transmit, the VREG pin is biased to 2.85 V and
draws 9 mA of current. When the VREG pin is low (0 V), the
device suspends itself into sleep mode (irrespective of supply
biasing). In this mode, the device draws less than 1 μA of
current.
RFOUT
RFOUT
15
14
11nH
Figure 21. RF Output
L2
VPOS1
39pF
C3
2.7pF
C4
C5
OPEN
C12
1µF
RFOUT
ADL5571