DEMO-MGA-2XX03 Datasheet, PDF (12/16 Pages) Broadcom Corporation. – 2.3-2.7 GHz 3x3mm WiMAX and WiFi Power Amplifi er

Flexible BCTRL Optimization
BCTRL voltage on MGA-22003 directly controls the bias current of the device. If the user requires lower current or
perhaps higher power than the typical operation, then this can be accomplished by a simple BCTRL change. A more
sophisticated use might include BCTRL as part of a closed loop system where software dynamically adjusts BCTRL
depending on the output power required.
Low Current Operation: 400mA at 25dBm Pout with
BCTRL = 1.8V and VCC = 3.3V
Example 1 is very typical of mobile device application
where ~400mA of current consumption is required. With
the above settings at full power of 25dBm, IDD drops from
500mA to 418mA with some trade-off in EVM but still
meeting SEM.
Idd Frequency Sweep (BCTRL = 1.4 to 2.5V)
Tambient = 25C and Pout = 25dBm and Vbat = 3.3
0.480
0.460
0.440
0.420
0.400
0.380
0.360
0.340
0.320
1V4 1V6
0.300
2300.00 2400.00
1V8 2V0 2V2 2V5
2500.00 2600.00 2700.00
Frequency [MHz]
Table 5. Low Current Biasing
Optimal settings for BCTRL (2.3G - 2.7G)
Pout
25dBm
24dBm
23dBm
Idsq
VCC = BSPLY = 3.3V
BCTRL
Idd
1.8V
418mA
1.7V
367mA
1.7V
330mA
x
94mA
EVM
-27.9dB
-27.6dB
-27.0dB
x
Table 6. Typical Biasing
Typical settings for BCTRL (2.3G - 2.7G)
Pout
25dBm
24dBm
23dBm
Idsq
VCC = BSPLY = 3.3V
BCTRL
Idd
2.8V
501mA
2.8V
464mA
2.8V
435mA
x
240mA
EVM
-32dB
-33dB
-35dB
x
Hi Power Operation: 26dBm Pout with
BCTRL = 2V and VCC = 5V
Example 2 is more typical of CPE applications where cur-
rent consumption is less important and higher power is
required. With BCTRL at 2V and VCC at 5V MGA-22003 is
able to achieve higher than 26dBm Pout and still meet
SEM. Generally as VCC increases SEM improves.
-20.00
-22.00
-24.00
-26.00
-28.00
-30.00
-32.00
-34.00
-36.00
2300
EVM Frequency Sweep (Vcc = 3.0 to 5.0V)
Tambient = 25C and Pout = 26dBm
3V3
3V6
4V2
5V0
2400
2500
2600
2700
Frequency [MHz]
12