Controller Section; Dc Power Distribution - Motorola MTM800 User Manual

4.1 - 16

Controller Section

For the Controller Section Block Diagram see Figure 4.1-5 on page 4.1-9.
This section describes the related circuits as follows:
• DC Power Distribution and RESET
• Microprocessor and Host Memories
• SPI
• RS232/USB
• Terminal Audio System
• RTC
• GPS
• SIM card connectivity
• GPIOs

DC Power Distribution

RTC VSTBY
9,3V
Analog_3.3V Digital_3.3V
3.3V_FN
U5103
U5102 U5321
LP2980 LP2980 LP2980
5V
ABACUS
FracN
9.3V
PCIC
IF
FE + Mixer TX - VCO
DC Power Input
The DC power of nominal 13.2 volts enters the terminal at connector J0301. Diode VR0300 acts as
protection against transients and wrong polarity of the supply voltage. The supply voltage is fed
directly to the RF PA, through the 3A fuse F0303 to the audio circuitry, through F0302 to the
expansion head and Enhanced Control Head, and through the 4A PCB fuse (F0301) to regulators
U0300, U0301, U0302, and the ON/OFF and VSTBY circuitry. The fuses protect the board from over
current in case of a short on the connector pins or circuit failure.
13,2V
Fuse
F0303
RF PA
Audio
9.3V
9.3V_TX
5V_TX 3V_TX
5V_FN
U5322 U0304 U0307
ADP3300 LP2951C
MC33275
Controller
4.6V
VSF
Escort VCOBIC
JAVELIN
RX - VCO
Figure 4.1-6 DC Power Distribution Diagram
13,2V
A+
Fuse
F0302
Fuse
F0301
I/O
9.3V
9.3V_TX 3V_DIG
9.3V 5VD
U0303 U0305
U0300 U0301
LM2941
LM2941 78M05
LP2951C
Ref.
Voltage
ON/OFF
Circuit
3V_TX 3V_DIG
FLASH
RAM
ADDAG
TX
THEORY OF OPERATION (TRANSCEIVER)
3 V
SW B+
Regulator
Regulator
LP2951
LP2941
Expansion
Head
1.8 V
1.55 V 3.3V_DIG 5V
U1105
U0306
Q0305 Regulator
LP2985 LP2951C LP2951
Head D
ON / OFF
9.3V
PATRIOT
UCM
Option
Option
ON / OFF
SW B+
U0302
LM2941
Accessory
GPS
Connector
Option
20 -PIN