AN1602 Freescale Semiconductor / Motorola, AN1602 Datasheet - Page 7

• Manufacturer Part Number: AN1602
• Description: AN1602 Application Note: Dual-Band PA Application w/DECT Capability Using Std RFICs
• Manufacturer: Freescale Semiconductor / Motorola

Control and Its Advantages
dynamic range for the GSM path. Figures 9 and 10 show
performance for the DCS path.
than –60 dBc even for the minimum output power (5.0 dBm)
when GMSK modulation is applied to the PA.
ramp is applied on V
the drain control for a PA versus gate control. The RF output
MOTOROLA SEMICONDUCTOR APPLICATION INFORMATION
Table 2. Minimum and Typical Performances for DCS Path at 3.6 V
ELECTRICAL CHARACTERISTICS
T
Frequency Range
V
V
I
Output Power at (GSM Pulse)
Output Power at (GSM Pulse; Low Voltage: V
Power Added Efficiency
Input Return Loss
Harmonic Output
Output Noise Power (P
A
SS
Figures 7 and 8 present rise and fall time within 30 dB
The transition is about 2.0 s in the worst case.
Figures 11 and 12 check that spurious levels are lower
Figure 13 shows the output power when a linear control
DD
SS
= 25 C unless otherwise noted)
2nd f
3rd f
o
o
ramp
out
Figure 6. Gain (1), Isolation (2) and Return Loss for DCS1800 Path at 3.6 V
Nominal; 100 kHz Bandwidth; 20 MHz above f
input. This depicts the superiority of
Characteristic
Freescale Semiconductor, Inc.
For More Information On This Product,
(V
D1, 2, 3
DD
= 3.0 V)
= 3.6 V, P
Go to: www.freescale.com
in
= 5.0 dBm, Peak Measurement at 12.5% Duty Cycle, 4.6 ms Period,
o
)
voltage/V
voltage up to approximately 1.5 V. Therefore, very simple,
low–cost techniques can be used to generate the V
voltage necessary to get the shaping and RF steps levels.
This eliminates all stability loop problems due to gate control
non–linearity.
linear control loop and requests a lower loop bandwith. As the
PA is in saturation within the full dynamic power range, AM to
AM conversion remains very good, even at low power level.
This transfer function shape leads to a very stable and
ramp
1710
30.5
Min
transfer function is linear for V
32
35
–
–
–
–
–
–
–
–4.0
33.5
Typ
–45
–35
–85
3.6
42
–
–
–
–
1785
Max
–10
–30
–30
–80
1.0
–
–
–
–
–
ramp
Unit
MHz
dBm
dBm
dBm
dBc
mA
dB
%
V
V
input
7
ramp