Front Panel Display Pcb And Controls; Schematic Diagrams - Mallinckrodt NELLCOR NPB-195 Service Manual

Section 11: Technical Supplement
11.8.9 Patient Data Storage

11.9 FRONT PANEL DISPLAY PCB AND CONTROLS

11.9.1 Display PCB
11.9.2 Membrane Keypad

11.10 SCHEMATIC DIAGRAMS

11-8
The LCD will display real time when trends are selected. A time stamp is
printed for each line of data on a printout. Real-time data is displayed and
printed as Day, Month, Year, Hours, Minutes, and Seconds.
Patient data is stored once every 5 seconds. A maximum of 24 hours of patient
data can be stored. Up to 50 alarm limit changes can be retained. Trend data
will be retained for a minimum of 30 days.
If battery power is disconnected or depleted, patient data will be lost. Data is
stored with error detection coding. If data stored in memory is corrupted, it is
discarded.
The Front Panel LCD display PCB displays patient data and status of the
monitor.
At power up, all indicators and pixels are illuminated to allow verification of
their proper operation. Next, the NPB logo and the software revision level are
displayed. After this cycle has been completed the instrument is ready to begin
monitoring.
The LCD allows the user to select among several different types of displays.
Graphs, which are used for trend screens, can be displayed. Real-time patient
data can include a plethysmographic waveform and digital values for SpO
BPM. If a plethysmograph is not desired, the operator can select to view only
digital data for SpO and BPM along with a blip bar to show pulse intensity.
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A membrane keypad is mounted as part of the top case. A ribbon cable from the
keypad passes through the top case and connects to the UIF PCB. Nine keys
allow the operator to access different functions of the NPB-195.
These keys allow the user to select and adjust the alarm limits, cycle power to
the unit, and to silence the alarm. Alarm volume and alarm silence duration can
also be adjusted via the keypad. Pressing the softkeys can access a number of
other functions. These functions are discussed in greater detail in Section 4.
Four LEDs are also part of the membrane keypad. These LEDs indicate AC
power available, low battery, pulse search, and alarm silence.
The following part locator diagrams and schematics are included in this section:
Figure 11-3: UIF PCB Front End Red/IR Schematic Diagram
Figure 11-4: Front End LED Drive Schematic Diagram
Figure 11-5: Front End Output Schematic Diagram
Figure 11-6: Front End Power Supply Schematic Diagram
Figure 11-7: Isolation Barrier EIA-232 Port Schematic Diagram
and
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