Controller Information; Overview; Radio Power Distribution - Motorola GP88s Service Manual

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

UNSWB+
Fuse
7.5V
Battery
PA, Driver
PCIC(ALC)
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.
Audio PA
R4
R1
SWB+
Control
MECH.
SWB+
On/Off Switch
Low Battery
Detect
Ant. SW
Figure 7-1 DC Power Distribution Block Diagram
Accessory
Jacks
Keypad/Option Board
Vdda
Vdda
Reg.
R3
R2
Vddd Vdda
Reg.
TX.
Led
LCD
MCU Micro P, ROM
Driver
& EEPROM
5V
Reg.
5V
Jumpers
R1
RF. AMP, IF AMP
R2
Ext. RX.
Buffer (NU)
R3
R4
Vdda
FRACTN
ASFIC_CMP
LVZIF
VCOBIC
Dual Vdd Single Vdd
Regulator Regulator
Scheme Scheme
Y Y
N N
N Y
Y N
Y N
7-1