WS1103 Ver la hoja de datos (PDF) - Avago Technologies
Número de pieza
componentes Descripción
Fabricante
WS1103 Datasheet PDF : 15 Pages
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Peripheral Circuit in Handset
Calibration
RF In
TX
FILTER
C2
C3
C1
MSM PA_RO
PA_ON
+2.85 V
VBATT
C5
C4
Vcc1
Vcc2
RF IN RF OUT
Vcont
GND
Vref
GND
WS1103
C6
C7
L1
Duplexer
RF Out
Output Matching Circuit
C8
Calibration procedure is shown in Figure 11. Two
calibration tables, high mode and low mode respective-
ly, are required for Cool PAM, which is due to gain differ-
ence in each mode. For continuous output power at the
mode change points, the input power should be adjust-
ed according to gain step during the mode change.
Offset Value (Difference between Rising Point and
Falling Point)
Offset value, which is the difference between the rising
point (output power where PA mode changes from low
mode to high mode) and falling point (output power
where PA mode changes from high mode to low mode),
should be adopted to prevent system oscillation. 3 to
5 dB is recommended for hysteresis.
NNOoTESt:es:
•• RecoRmmeecndoedmvolmtageefnor dVreef ids 2.v85oVl. tage for Vref is 2.85 V.
• Place C1 near to Vref pin. • Place C1 near to Vref pin.
• Place C3 and C4 close to pin 1 (Vcc1) and pin 10 (Vcc2). These capacitors can affect the RF performance.
•• Use 5P0 lΩatrcaensmCis3sionalninedbeCtw4eencPlAoMsaend tDouplepxeirnan1d m(aVkecitcas1s)hoartnasdpospsiibnle to8re(dVucce cco2nd)u.ction loss.
• π-typTe hcirecusitetopcolaogpy ias gcoiotdotorussecfoar mnatcahfinfgeccirctuitt bheteweRenFPApanedrDfuoplerxmer. ance.
• Use 50 W transmission line between PAM and Duplexer and make it
as short as possible to reduce conduction loss.
• π-type circuit topology is good to use for matching circuit between
PA and Duplexer.
Figure 10. Peripheral circuit
Average Current & Talk Time
Probability Distribution Function implies that what is
important for longer talk time is the efficiency of low
or medium power range rather than the efficiency at
full power. WS1103 idle current is 13 mA and operating
current at 16 dBm is 65 mA at nominal condition. This PA
with low current consumption prolongs talk time by no
less than 30 minutes compared to other PAs.
TX_AGC
GAIN
Low Mode
High Mode
Falling Rising
Min. PWR
Pout
Max. PWR
Figure 11. Calibration procedure
5.00
4.50
4.00
3.50
3.00
2.50
2.00
1.50
1.00
0.50
0
-50
CDG Urban
CDG Suburban
-40
-30
Conventional PAM
-20
-10
0
10
PA Out (dBm)
Digitally Controlled PAM
Figure 13. CDMA power distribution function
Low Mode
High Mode
Pout
Falling
Rising
Figure 12. Setting of offset between rising and falling power
700
600
500
400
300
200
100
0
20
30
Cool PAM
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