THEORY OF OPERATION Chapter 2
2 - 11
2.2.10 I/O Board
The I/O board contains the interface to external electronics for the pump. This includes the
battery charge control circuitry and the serial data interfaces.
2.2.10.1 Power Source
• Battery Charger
The battery charger circuit provides a tapered charge of the battery pack.
2.2.10.2 Zebra Strip Pass Through
J10 provides pads on the circuit board for connection to the zebra strip connector to the
Syringe Clamp. These signals pass through and connect to J2.
2.2.10.3 Speaker Pass Through
The speaker is connected to J15-1 and J15-2 on the I/O board. These signals pass
directly to J2-23 and J2-24.
2.2.10.4 Real Time Clock Power
The real time clock is always connected to the battery of the pump via the net “F_VB”. It
gets its power after the fuse F2 and feeds to the Analog board on J2-21.
2.2.10.5 Serial Port
The I/O board provides two different means for serial communication to the pump. It
provides a TTL level connection via the 8 pin DIN connector on the bottom of the pump or
a DB-9 connector with RS232 level serial signals on the back of the device. Software
configuration is required to enable or disable either serial port.
• TTL Level (DIN Connector)
The TTL level serial port can be used for monitoring and control of the pump. It is also
used to program the flash memory via the master bootstrap loader program.
J11-0 is a electromagnetic shield chassis ground.
J11-1 is the “Charger+(IN)” connection. It is ESD protected by Z3 and C3.
J11-2 is “RXD(IN).” This line is protected from ESD via R20, Z8 and C8. It is pulled down
by R5 and isolated by R6 into U3C-7. From U3C-6 it passes through U4B to connect to
“RS232_RXD” on J2-7.
To Next Page
Loading...
Need help?
General
