Respironics Trilogy 02, Technical Information

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P
AGE
4-4
T
RILOGY
S
ERVICE
& T
ECHNICAL
I
NFORMATION
1002735, V
ER
. 05
Discharge Switch - The discharge switches (Q7, Q8, Q9 & Q10) are used to control the discharge of the
lithium ion batteries. The smart battery system manager (U3) controls the discharging of the internal and
detachable lithium ion battery. The input MOSFETs (Q7, Q8) are turned OFF to prevent any accidental
charging of a battery if reverse current is measured in the battery discharge path.
3.3VDC Supply - There are two 3.3VDC supplies generated on the power management board. First, the linear
voltage regulator (U12) generates a 3.3VDC supply used when the ventilator is in the low power mode. And
second, the switching regulator (U9) generates a 3.3VDC supply used by the logic circuitry on the board. The
switching regulator (U9) is in shutdown mode when the Trilogy ventilator is in low power mode.
4.3 S
YSTEM
B
OARD
A system board is the central printed circuit board in the Trilogy ventilator. It contains circuitry to interface with
all other printed circuit board assemblies in the Trilogy ventilator with the exception of the power supply board.
It generates and manages most of the internal power supply voltages for the Trilogy ventilator and contains the
complete motor control circuitry.
F
IGURE
4-3 S
YSTEM
B
OARD
B
LOCK
D
IAGRAM
Over
Current
Protection
Power
Management
Board
12VDC
DC-DC
Converter
14VDC
3.3VDC
Analog
Power Fail
Capacitor
3.3VDC
DSP
5VDC
4.8VDC
Power Fail
3.3VDC
CPU
3-Phase
Motor
Inverter
FET
Driver
FET
Driver
Motor
Current
Sense
Motor
Voltage
Sense
Over
Voltage
Protection
DSP
Off - Board
Bulk
Capacitor
Motor
Valve
Control
CPU
Daughter
Card
EEPROM
Analog
Multiplexer
RTC
CPLD JTAG
CCFL
Inverter
CCFL
Control
Sensor
Board
Level
Shifter
Vcc
Supervisor
Front
Panel
Board
Active
Exhalation
Valve
3.3VDC
CPLD
SD
Card
Fans
Coin Cell
Battery
LCD
Interface
Board
I/O
Expander