AD8314ACPZ-REEL Analog Devices Inc, AD8314ACPZ-REEL Datasheet - Page 18

• Manufacturer Part Number: AD8314ACPZ-REEL
• Manufacturer: Analog Devices Inc

Specifications of AD8314ACPZ-REEL

• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 8
• Lead Free Status / RoHS Status: Compliant

AD8314
OPERATION AT 2.7 GHz
While the AD8314 is specified to operate at frequencies up to
2.5 GHz, it works at higher frequencies, although it does exhibit
slightly higher output voltage temperature drift. Figure 43
shows the transfer function of a typical device at 2.7 GHz, at
ambient as well as hot and cold temperatures.
Figure 44 shows the transfer function of the AD8314 when
driven by both an unmodulated sine wave and a 64 QAM
signal. As previously discussed, the higher peak-to-average ratio
of the 64 QAM signal causes an increase in the intercept.
In this case, the intercept increases by approximately 1.5 dB,
causing the overall transfer function to drop by the same
amount. For precision operation, the AD8314 should be
calibrated for each signal type that is driving it.
1.2
1.0
0.8
0.6
0.4
0.2
0
–70
–60
–50
Figure 43. Operating at 2.7 GHz
INPUT
VSET
INPUT POWER (dBm)
–40
+25°C
–30
+80°C
–40°C
OPEN
R8
LK1
R1
0Ω
–20
+80°C
–10
R7
0Ω
+25°C
52.3Ω
SW1
VPOS
R2
C4
(OPEN)
0
–40°C
Figure 45. Evaluation Board Schematic
1
2
3
4
10
3
2
1
0
–1
–2
–3
RFIN
ENBL
VSET
FLTR
AD8314
Rev. B | Page 18 of 20
COMM
VPOS
V_DN
V_UP
8
7
6
5
USING THE LFCSP PACKAGE
On the underside of the LFCSP package, there is an exposed,
compressed paddle. This paddle is internally connected to the
chip’s ground. While the paddle can be connected to the printed
circuit board’s ground plane, there is no thermal or electrical
requirement to do this.
EVALUATION BOARD
Figure 45 shows the schematic of the AD8314 MSOP
evaluation board. The layout and silkscreen of the component
side are shown in Figure 46 and Figure 47. An evaluation board
is also available for the LFCSP package. (For exact part numbers,
see the Ordering Guide.) Apart from the slightly smaller device
footprint, the LFCSP evaluation board is identical to the MSOP
board. The board is powered by a single supply in the 2.7 V to
5.5 V range. The power supply is decoupled by a single 0.1 μF
capacitor. Additional decoupling, in the form of a series resistor
or inductor in R9, can also be added. Table 7 details the various
configuration options of the evaluation board.
0.1µF
C1
0Ω
R3
1.2
1.0
0.8
0.6
0.4
0.2
0
–70
0Ω
R5
Figure 44. Shift in Transfer Function due to 64 QAM
–60
R4
(OPEN)
R6
(OPEN)
R9
0Ω
–50
INPUT POWER (dBm)
–40
C2
(OPEN)
C3
(OPEN)
CW
–30
64 QAM
V
–20
V_DN
V_UP
POS
CW
64 QAM
–10
0
10
3
2
1
0
–1
–2
–3