Motorola GP Series Detailed Service Manual page 131

Controller Information
ModB/Vstby Supply
Under various conditions, the supply to the ModB/Vstby would vary. Table 7-2 shows these
conditions and circuits in operation.
Radio Off
Primary battery removed
Flash Mode
Table 1-2: ModB/Vstby Supply Modes
Condition
Vdd supply voltage via CR411
• Vdd turned off
• Q416 gate is pulled low by R462
• Q416 is switched on
• U410 supplies 3.2V to ModB/Vstby
• Vdd turned off
• Q416 gate is pulled low by R462
• Q416 is switched on
• LiO battery provides 3.2V to ModB/Vstby
• Boot_Ctrl line pull low
• ModA & ModB goes low
• Processor in boot-strap mode
• Flashing enabled
Circuit Operation
1-19