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www.fairchildsemi.com
RMPA2265 Rev. I
RMPA2265 Dual Band WCDMA Power Edge™ Power Amplifier Module 1850 to 1910 MHz and 1920 to 1980 MHz
Performance Data: 1850 to 1910 MHz
Efficiency Improvement Applications
In addition to high-power/low-power bias modes, the efficiency
of the PA module can be significantly increased at backed-off RF
power levels by dynamically varying the supply voltage (Vcc)
applied to the amplifier. Since mobile handsets and power
amplifiers frequently operate at 10–20 dB back-off, or more, from
maximum rated linear power, battery life is highly dependent on
the DC power consumed at antenna power levels in the range of
0 to +16dBm. The reduced demand on transmitted RF power
allows the PA supply voltage to be reduced for improved
efficiency, while still meeting linearity requirements for WCDMA
modulation with excellent margin. High-efficiency DC-DC
converters are now available to implement switched-voltage
operation.
With the PA module in low-power mode (Vmode = 2.0V) at
+16dBm output power and supply voltages reduced from 3.4V
nominal down to 1.2V, power-added efficiency is more than
doubled from 9 percent to 25 percent (Vcc = 1.2V) while
maintaining a typical ACLR1 of -40dBc and ACLR2 of less than
-54 dBc. Operation at even lower levels of Vcc supply voltage
are possible with a further restriction on the maximum RF output
power.
DC Turn On Sequence:
1. Vcc1 = Vcc2 = 3.4V (typical)
2. Vref = 2.85V (typical)
3. High-Power: Vmode = 0V (Pout > 16dBm)
Low-Power: Vmode = 2.0V (Pout < 16dBm)
RMPA2265 3x3 WCDMA PA at US-PCS Freq
Vcc=3.4V, Vref=2.85V, Vmode=0V, Pout=27.5dBm
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
31.0
32.0
33.0
1850 1880 1910
Frequency (MHz)
Gain (dB)
RMPA2265 3x3 WCDMA PA at US-PCS Freq
Vcc=3.4V, Vref=2.85V, Vmode=0V, Pout=27.5dBm
35.0
36.0
37.0
38.0
39.0
40.0
41.0
42.0
43.0
44.0
45.0
1850 1880 1910
Frequency (MHz)
PAE (%)
RMPA2265 3x3 WCDMA PA at US-PCS Freq
Vcc=3.4V, Vref=2.85V, Vmode=0V, Pout=27.5dBm
-50.0
-48.0
-46.0
-44.0
-42.0
-40.0
-38.0
-36.0
-34.0
-32.0
-30.0
1850 1880 1910
Frequency (MHz)
ACLR1 (dBc)
RMPA2265 3x3 WCDMA PA at US-PCS Freq
Vcc=3.4V, Vref=2.85V, Vmode=0V, Pout=27.5dBm
-65.0
-63.0
-61.0
-59.0
-57.0
-55.0
-53.0
-51.0
-49.0
-47.0
-45.0
1850 1880 1910
Frequency (MHz)
ACLR2 (dBc)
