Motorola GP88s

7-1
Section 7
CONTROLLER INFORMATION
1.0 Overview
This section provides a detailed theory of operation for the radio and its components.
2.0 Radio Power Distribution
Figure 7-1 illustrates the DC distribution throughout the radio board. A 7.5V battery (BATT 7.5V)
supplies power directly to the electronic on/off control as UNSWB+. When the radio is turned on,
MECH_SWB+ (on/off/volume control) will trigger the electronic on/off control(momentary-on path),
then SWB+ is distributed as shown in Figure 7-1. Vdda from 3.3V Vdda regulator will then supply
the microprocessor. Data is then sent to ASFIC_CMP to turn on GCB4(DAC). GCB4 will take over
the momentary-on path within 12ms. SWB+ will continue to support the whole board until the radio
is turned off.
Figure 7-1 DC Power Distribution Block Diagram
Control
On/Off Switch
SWB+
Fuse
Low Battery
Detect
Ant. SW
PCIC(ALC)
PA, Driver
7.5V
Audio PA
Vddd
Reg.
5V
ASFIC_CMP
VCOBIC
FRACTN
LVZIF
LCD
Driver
5V
RF. AMP, IF AMP
Ext. RX.
MECH.
SWB+
UNSWB+
TX.
Vdda
Reg.
R1
R4
R2
R3
Vdda
Accessory
Jacks
Keypad/Option Board
Vdda
Battery
Reg.
MCU Micro P, ROM
& EEPROM
Buffer (NU)
Led
Jumpers
Dual Vdd
Regulator
Scheme
Single Vdd
Regulator
Scheme
R1 Y Y
R2 N N
R3 N Y
R4 Y N
Vdda Y N