GE Brivo OEC 715, Service Manual

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System Overview
2-19
Optical coupling
-
Optical coupling circuit is responsible for changing voltage level and isolating the ground of circuit at
each sides of optical coupler.
DAC
-
DAC (Digital Analog Converter) circuit is responsible for output analog signal, such as KV setting, mA
setting and mA pre-heat.
VFC
- VFC (Voltage Frequency Converter) circuit is responsible for converting mA signal to frequency value
in order to implement mAs function.
Communication
-
RS422 protocol is used for MCU to communicate with workstation or DAP.
- SPI protocol is used for MCU to communicate with Control Panel.
Indication
-
Indication circuit includes LED and buzzer, which are controlled by MCU and peripheral controller.
Miscellaneous hardware
-
Other circuits include power supply, supervisor circuit, watchdog circuit, clock generator, and security
control, etc.
Power Distribution
Power Supply Overview
The power of MCB is drove by power supply 1 & 2 via mother board, and +3.3V, +2.5V & +1.2V are generated
from +5V_PS1. Power supplies are listed as follows.
Name Description Source Scale Pin Comment
+5V_PS1 +5V power supply PS1 +5V J2-A5/B5/C5 -
GND_+5V Reference of +5V_PS1 PS1 0V J2-A4/B4/C4 -
-15V_PS1 -15V power supply PS1 -15V J2-A15/A16 -
+15V_PS1 +15V power supply PS1 +15V J2-C15/C16 -
AGND Reference of -15V_PS1 & +15V_PS1 PS1 0V J2-A9/B9/C9 -
+24V_PS1 +24V power supply PS1 +24V J1-B9 -
GND_+24V_PS1 Reference of +24V_PS2 PS1 0V J1-B10 -
+15V_PS1_D +15V power supply PS1 +15V J1-A29/B29/C29 -
GND_+15V_PS1_D Reference of +15V_PS1_D PS1 0V J1-A12/B12/C12 -
-15V_PS1_D -15V power supply PS1 -15V J1-C32 -
GND_-15V_PS1_D Reference of -15V_PS1_D PS1 0V J1-A32 -
+24V_PS2 +24V power supply PS2 +24V J1-A1/B1/C1 -
GND_+24V_PS2 Reference of +24V_PS2 PS2 0V J1-A6/B6/C6 -
+12V_PS2 +12V power supply PS2 +12V J1-B5 -
GND_+12V_PS2 Reference of +12V_PS2 PS2 0V J1-A5 -
+3.3V Internal power +5V_PS1 +3.3V - By LM1084
+2.5V Internal power +5V_PS1 +2.5V - By LM1084
+1.2V Internal power +5V_PS1 +1.2V - By LM1084
Grounding Connection
All the grounds of power are connected by mother board with one point strategy.