SKY65152-11 Datasheet, PDF (7/14 Pages) Skyworks Solutions Inc. – 2.4-2.5 GHz WLAN Power Amplifier

DATA SHEET • SKY65152-11 POWER AMPLIFIER
Evaluation Board Description
The SKY65152-11 Evaluation Board is used to test the
performance of the SKY65152-11 PA. An Evaluation Board
schematic diagram is provided in Figure 15. An assembly drawing
for the Evaluation Board is shown in Figure 16.
An Evaluation Board layer detail drawing is shown in Figure 17.
Layer detail physical characteristics are noted in Figure 18.
Table 5 provides the Bill of Materials (BOM) list for Evaluation
Board components.
Circuit Design Considerations
The following design considerations are general in nature and
must be followed regardless of final use or configuration:
1. Paths to ground should be made as short as possible.
2. The ground pad of the SKY65152-11 has special electrical
and thermal grounding requirements. This pad is the main
thermal conduit for heat dissipation. Since the circuit board
acts as the heat sink, it must shunt as much heat as possible
from the device. Therefore, design the connection to the
ground pad to dissipate the maximum wattage produced by
the circuit board. Multiple vias to the grounding layer are
required.
3. Bypass capacitors should be used on the DC supply lines. An
RF inductor is required on the VCC supply line to block RF
signals from the DC supply. Refer to the schematic drawing in
Figure 15 for further details.
4. The RF lines should be well separated from each other with
solid ground in between traces to maximize input-to-output
isolation.
NOTE: A poor connection between the slug and ground increases
junction temperature (TJ), which reduces the lifetime of the
device.
Evaluation Board Test Procedure
Step 1: Connect a +5 V supply to the VCC1, VCC2, VCC3, VREF1,
VREF2, VREF3, VC_BIAS, VCC_DET, and PA_ENB pins. If
available, enable the current limiting function of the
power supply to 1000 mA.
Step 2: If desired, connect a voltage meter to the V_DET pin.
Step 3: Connect a signal generator to the RF signal input port.
Set it to the desired RF frequency at a power level of
–15 dBm or less to the Evaluation Board. DO NOT enable
the RF signal.
Step 4: Connect a spectrum analyzer to the RF signal output port.
Step 5: Enable the power supply.
Step 6: Enable the RF signal.
Step 7: Take measurements.
CAUTION: If the input signal exceeds the rated power, the
SKY65152-11 Evaluation Board can be permanently
damaged.
NOTE: It is important to adjust the VCC voltage source so that
+5 V is measured at the board. The high collector currents
will drop the collector voltage significantly if long leads are
used. Adjust the bias voltage to compensate.
PA Enable (0-5 V)
Bias Voltage (5 V)
Reference Voltage (5 V)
RF Output
C11
10 μF
C1
3300 pF
R1
560 Ω
C2
3300 pF
R2
180 Ω
R3
180 Ω
20
1 _GND
2 _GND
3 _{PA_ENB}
4
VC_BIAS
5 _VREF1
6
VREF2
7
19
18
17
SKY65152-11
VCC1 ¹⁶
15
VCC_DET
14
V_DET
13
VCC2
N/C ¹² ×
11
VCC3
8
9
10
C5
8.2 pF
R5
300 Ω
C15
10 μF
C6
3300 pF
L2
27 nH
C7
8.2 pF
C8
8.2 pF
C16
10 μF
C10
8.2 pF
C17
10 μF
Figure 15. SKY65152-11 Evaluation Board Schematic
RF Input
Collector Voltage 1 (5 V)
Detector Supply Voltage (5 V)
Detector Output
Collector Voltage 2 (5 V)
Collector Voltage 3 (5 V)
S1502
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
200968F • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • October 19, 2009
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