RMPA2259 Fairchild Semiconductor, RMPA2259 Datasheet - Page 5

• Manufacturer Part Number: RMPA2259
• Description: IC MOD RF POWER AMP 10PIN 4X4LCC
• Manufacturer: Fairchild Semiconductor

Specifications of RMPA2259

• Current - Supply: 50mA
• Frequency: 1.92GHz ~ 1.98GHz
• Gain: 24dB
• Noise Figure: 3dB
• Package / Case: 11-LCC
• Rf Type: W-CDMA
• Voltage - Supply: 3V ~ 4.2V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• P1db: -
• Test Frequency: -
• Other names: RMPA2259TR

©2004 Fairchild Semiconductor Corporation
Efficiency Improvement Application
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–
20dB 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 CDMA modulation
with excellent margin. High-efficiency DC-DC converters
are now available to implement switched-voltage operation.
Typical Characteristics
Low-Power Mode (Po = +16dBm)
-35
-37
-39
-41
-43
-45
-47
-49
-51
-53
-55
30
29
28
27
26
25
26
23
22
21
20
1900
1900
V
V
V
V
V
V
V
V
V
CC
CC
CC
CC
CC
CC
CC
CC
CC
RMPA2259 W-CDMA 4x4mm
RMPA2259 W-CDMA 4x4mm
= 3.4V
= 3.0V
= 1.2V
= 2.0V
= 1.5V
= 3.4V
= 1.5V
= 2.0V
= 1.2V
Vref = 2.85V, Pout = 16dBm
Vref = 2.85V, Pout = 16dBm
1920
1920
FREQUENCY (MHz)
FREQUENCY (MHz)
1940
1940
Figure 5.
Figure 7.
1960
1960
(continued)
V
CC
= 3.0V
1980
1980
2
2
PAM
PAM
2000
2000
The following charts show measured performance of the
PA module in low-power mode (Vmode = +2.0V) at
+16dBm output power and over a range of supply voltages
from 3.4V nominal to 1.2V. Power-added efficiency is more
than doubled from 9.5 percent to nearly 25 percent (Vcc =
1.2V) while maintaining a typical ACLR1 of -46dBc and
ACLR2 of approximately -60dBc.
Operation at even lower levels of Vcc supply voltage are
possible with a further restriction on the maximum RF
output power. As shown below, the PA module can be
biased at a supply voltage of as low as 0.7V with an
efficiency as high as 10–12 percent at +8dBm output
power. Excellent signal linearity is still maintained even
under this low supply voltage condition.
30
25
20
15
10
-50
-52
-54
-56
-58
-60
-62
-64
-66
-68
-70
5
1900
1900
V
V
V
V
V
V
V
V
V
RMPA2259 W-CDMA 4x4mm
CC
CC
CC
RMPA2259 W-CDMA 4x4mm
CC
CC
CC
CC
CC
CC
= 1.2V
= 1.5V
= 3.4V
= 2.0V
= 3.0V
= 1.2V
= 1.5V
= 2.0V
= 3.0V
Vref = 2.85V, Pout = 16dBm
Vref = 2.85V, Pout = 16dBm
1920
1920
V
CC
= 3.4V
FREQUENCY (MHz)
FREQUENCY (MHz)
1940
1940
Figure 6.
Figure 8.
1960
1960
2
2
1980
1980
PAM
PAM
RMPA2259 Rev. D
2000
2000