
Application Information
MOTOROLA WIRELESS
RF PRODUCT DEVICE DATA
MMM5063
2–8
5
4.3 Application Schematics and Printed Circuit Boards
Figure 18. Open Loop Control Application Schematic
Figure 18 represents the complete Power Amplifier implementation including the MMM5063 Amplifier
Module and the Control Circuitry. This functionality is realized with two separate printed circuit boards;
the PA Evaluation Circuit with schematic shown in Figure 21 and PCB Layout shown in Figure 23, and the
Power Amplifier Control Loop with schematic shown in Figure 22 and PCB Layout shown in Figure 24.
The PA Evaluation Circuit is straightfoward and, due to the MMM5063’s high level of integration,
requires only a few passive components around the package. These components are mainly de-coupling
capacitors.
The Power Amplifier Control Loop is based on an operational amplifier driving a PMOS transistor. The
PMOS device functions as a linear drain voltage regulator controlled by V
ramp
with a typical gain of 2
which is set through the resistive divider R4 and R5 as shown in Figure 22. To control output power
through the drain, V
apc
must be indexed to the drain voltage to prevent the PA Section from drawing
excessive current especially at low output power. Nevertheless, V
apc
should stay above 0.8 V to provide
sufficient gain for the line-up. Figure 19 describes the application circuit used to control V
apc
through the
drain voltage. It uses V
reg
to pre-position V
apc
at 0.9 V and add a voltage which is dependent on the drain
Voltage.
Figure 19.
GSM Out
DCS/PCS Out
MMM5063
V
dB
V
d
V
APC
CE
PMOS
[Note 1]
Battery
V
ramp
V
reg
V
GSM In
DCS/PCS In
[Note 2]
NOTES:
1. Op/Amp is either external (with an enable pin CE) or in an ASIC.
2. The MMM5063 requires 4 to 6 RF/LF decoupling capacitors (not shown).
V
reg
= 2.8 V
0 V < V
drain
< V
BAT
V
apc
R7 = 560
R8 = 1.0 k
R
VAPC
= 700
Internal to the die
F
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
.