SERVICE MANUAL NPB-190 Pulse Oximeter Caution: Federal law (U.S.) restricts this device to sale by or on the order of a physician. To contact Mallinckrodt’s representative: In the United States, call 1.800.635.5267 or 314.654.2000; outside of the United States, call your local Mallinckrodt representative. 1999 Mallinckrodt Inc. All rights reserved.
Mallinckrodt, Inc. 675 McDonnell Boulevard P.O. Box 5840 St. Louis, MO 63134 Tel 314.654.2000 Toll Free 1.800.635.5267 Nellcor Puritan Bennett 4280 Hacienda Drive Pleasanton, CA 94588 USA Mallinckrodt Europe BV Hambakenwetering 1 5231 DD’s-Hertogenbosch The Netherlands Tel +31.73.6485200 Nellcor Puritan Bennett is a wholly owned subsidiary of Mallinckrodt Inc. Nellcor and Nellcor Puritan Bennett are trademarks of Mallinckrodt Inc.
TABLE OF CONTENTS List of Figures List of Tables Table Of Contents ....................................................................................... List Of Figures......................................................................................... List Of Tables.......................................................................................... Section 1: Introduction ............................................................................... 1.1 Manual Overview........................
Table of Contents 8.2 Repacking in Original Carton ....................................................... 8.3 Repacking in a Different Carton................................................... Section 9: Specifications............................................................................ 9.1 General ........................................................................................ 9.2 Electrical....................................................................................... 9.
Table of Contents LIST OF FIGURES Figure 1-1: NPB-190 Front Panel.................................................................. Figure 1-2: NPB-190 Rear Panel .................................................................. Figure 3-1: NPB-190 Controls....................................................................... Figure 3-2: Self-Test Display......................................................................... Figure 3-3: Adjusting High %SpO2 Alarm Limit .................................
Table of Contents LIST OF TABLES Table 3-1: Dynamic Operating Range.......................................................... Table 3-2: Earth Leakage Current Limits ..................................................... Table 3-3: Enclosure Leakage Current Limits.............................................. Table 3-4: Patient Leakage Current Limits .................................................. Table 3-5: Patient Leakage Current Test Configurations - Mains Voltage on the Applied Part .................
SECTION 1: INTRODUCTION 1.1 1.2 1.3 1.4 1.1 Manual Overview NPB-190 Pulse Oximeter Description Power-On Self Test Related Documents MANUAL OVERVIEW This manual contains information for servicing the Nellcor model NPB-190 Pulse Oximeter. Only qualified service personnel should service this product. Before servicing the NPB-190, read the operator’s manual carefully for a thorough understanding of operation. Warning: Explosion hazard.
Section 1: Introduction 1 2 3 4 5 6 7 8 9 11 10 NPB190 15 14 13 12 Figure 1-1: NPB-190 Front Panel 1. 2. 3. 4. 5. 6. 7. 8. SpO2 Sensor Port Power On/Standby Button AC/Battery Charging Indicator Low Battery Indicator %SpO2 Display Pulse Amplitude Indicator Pulse Beats per Minute Display Alarm Silence Indicator 9. 10. 11. 12. 13. 14. 15.
Section 1: Introduction Upon completion of the POST display test, the software versions will be displayed for approximately 2 seconds. Two versions are displayed: • The first version is indicated by the numeral “1” in the leftmost segment of the %SpO2 display. The series of digits and decimal points displayed to the right of the “1” represent the main processor software version. • The second version is indicated by the numeral “2” in the leftmost segment of the %SpO2 display.
SECTION 2: ROUTINE MAINTENANCE 2.1 Cleaning 2.2 Periodic Safety and Functional Checks 2.3 Battery 2.1 CLEANING Caution: Do not immerse the NPB-190 or its accessories in liquid or clean with caustic or abrasive cleaners. Do not spray or pour any liquid on the monitor or its accessories. To clean the NPB-190, dampen a cloth with a commercial, nonabrasive cleaner and wipe the exterior surfaces lightly. Do not allow any liquids to come in contact with the power connector, fuse holder, or switches.
SECTION 3: PERFORMANCE VERIFICATION 3.1 3.2 3.3 3.4 3.1 Introduction Equipment Needed Performance Tests Safety Tests INTRODUCTION This section discusses the tests used to verify performance following repairs or during routine maintenance. All tests can be performed without removing the NPB-190 cover. All tests except the battery charge and battery performance tests must be performed as the last operation before the monitor is returned to the user.
Section 3: Performance Verification 2. Verify that the monitor is off and that the AC Power/Battery Charging indicator is lit. 3. Charge the battery for at least 14 hours. 3.3.2 Performance Tests The power-up performance tests (3.3.2.1 and 3.3.2.2) verify the following monitor functions: • • Power-On Self-Test Factory Power-On Defaults and Alarm Limit Ranges On/Standby Alarm Silence NPB-190 Lower Alarm Upper Alarm Limit Limit Adjust Down Adjust Up Figure 3-1: NPB-190 Controls Note: 3.3.2.
Section 3: Performance Verification a. All indicators light for a few seconds as illustrated in Figure 3-2. LEDs illuminated 888 displayed LED illuminated NPB190 10 segments LED illuminated illuminated Figure 3-2: Self-Test Display b. The software version is displayed and the AC Power/Battery Charging indicators remain on. c. When a sensor is connected a zero is displayed in each window, a 1second Power-On Self-Test (POST) beep sounds and the Pulse Search LED is illuminated.
Section 3: Performance Verification 2. Press the Upper Alarm Limit button. Press and hold the Adjust Down button. Verify that the %SpO2 display reduces to a minimum of “85”. Note: 3. A decimal point to the right of the value in either display indicates that the alarm limits are not power-on default values. Press the Lower Alarm Limit button. Verify that the monitor emits a single beep and that the %SpO2 display indicates an alarm limit of “85” for 3 seconds.
Section 3: Performance Verification 10. Press the Power On/Standby button to turn the unit off. Turn the unit back on. 11. Press and release the Upper Alarm Limit button. Verify that the %SpO2 display indicates an alarm limit of “100”. 12. Press and release the Lower Alarm Limit button. Verify that the %SpO2 display indicates an alarm limit of “85”. 13. Press the Upper Alarm Limit button two times rapidly. Verify that the pulse rate display indicates an alarm limit of “170”. 14.
Section 3: Performance Verification a. The pulse blip bar begins to track the artificial pulse signal from the SRC-2. b. The pulse tone is heard. c. Zeroes are displayed in the %SpO2 and pulse rate displays. d. After about 10 to 20 seconds, the monitor displays oxygen saturation and pulse rate as specified by the tester. Verify that the values are within the following tolerances: Oxygen Saturation Range 79% to 83% Pulse Rate Range 37 to 39 bpm e. 5.
Section 3: Performance Verification 3.3.3.1.2 Alarm Volume Control After completing the procedure in paragraph 3.3.3.1.1: 1. Press and hold the Alarm Silence button for more than 3 seconds. Verify the following: a. “OFF” is displayed for approximately 3 seconds. b. After 3 seconds, a steady tone is heard at the default alarm volume setting, the %SpO2 display indicates “VOL”, and the pulse rate display indicates the default setting of 5. Figure 3-8: Alarm Volume Display 3.3.3.1.3 3.3.3.1.4 2.
Section 3: Performance Verification Table 3-1: Dynamic Operating Range RATE 38 112 201 201 3.3.3.1.5 The Nurse Call tests must be performed with the instrument operating on AC power. 1. Connect the negative lead of a voltmeter to pin 10 and positive to pin 11 of the serial port on the back of the instrument (Figure A-1 in appendix). Ensure that the audible alarm is not silenced or turned off. 2. Set the SRC-2 to create an alarm condition.
Section 3: Performance Verification 1. Connect the monitor to an AC power source. 2. Connect an EC-4 or EC-8 sensor input cable to the monitor. 3. Connect a D-25 sensor to the sensor input cable. 4. Press the Power On/Standby button to turn the monitor on. 5. Leave the sensor open with the LEDs and photodetector visible. 6. After the monitor completes its normal power-up sequence, verify that the sensor LED is brightly lit. 7.
Section 3: Performance Verification • • Ground Integrity Electrical Leakage 3.4.1 Ground Integrity This test checks the integrity of the power cord ground wire from the AC plug to the instrument chassis ground. The current used for this test is < 6V RMS 50 or 60 Hz and 25 A. 1. Connect the monitor AC mains plug to the analyzer as recommended by the analyzer operating instructions. 2.
Section 3: Performance Verification AAMI/ANSI is 120 VAC 60 Hz, and for IEC 601-1 the applied voltage is 264 VAC 50 to 60 Hz. 1. Connect the monitor AC plug to the electrical safety analyzer as recommended by the analyzer operating instructions. 2. Place a 200 cm2 foil in contact with the instrument case making sure the foil is not in contact with any metal parts of the enclosure that may be grounded. Measure the leakage current between the foil and earth.
Section 3: Performance Verification Table 3-4: Patient Leakage Current Limits AC LINE POLARITY Normal Normal Normal Reverse Reverse Reverse 3.4.2.
SECTION 4: AUDIBLE ALARM SETTINGS & SERVICE MENU 4.1 Introduction 4.2 Audible Alarm Settings 4.3 Service Menu 4.1 INTRODUCTION This section discusses use of the service menu to reconfigure power-on default values, and how to control the behavior of the audible alarm. 4.2 AUDIBLE ALARM SETTINGS The following paragraphs describe how to change the behavior of the audible alarm. Operators can select the volume of the alarm and the duration of alarm silence. Controls for the NPB-190 are shown in Figure 4-1.
Section 4: Audible Alarm Settings & Service Menu 2. 4.3 After 3 seconds, while still pressing the Alarm Silence button, the Adjust Up or Adjust Down button can be used to select alarm volumes from 1 to 10. Select a level that is suitable for the monitor’s location. SERVICE MENU The menu items listed below should be accessed only by a qualified service technician. Power-on default values can be changed for the behavior of the audible alarm, alarm limits, and for the serial port. 4.3.
Section 4: Audible Alarm Settings & Service Menu 4.3.3 Menu Item 2 (Return to Default Settings) Menu item 2 resets the monitor to factory default settings as shown in table 4-1.
Section 4: Audible Alarm Settings & Service Menu 2. When the desired option is indicated in the display, press the Upper Alarm Limit button to save the current selection. Three tones will sound to indicate that the change has been accepted. 4.3.8 Menu Item 7 Do not use. For use by Mallinckrodt Customer Service Engineer. 4.3.9 Menu Item 8 Do not use. For use by Mallinckrodt Customer Service Engineer. 4.3.10 Menu Item 9 Do not use. For use by Mallinckrodt Customer Service Engineer.
SECTION 5: TROUBLESHOOTING 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.1 Introduction How to Use this Section Who Should Perform Repairs Replacement Level Supported Obtaining Replacement Parts Troubleshooting Guide Error Codes INTRODUCTION This section explains how to troubleshoot the NPB-190 if problems arise. Tables are supplied that list possible monitor difficulties, along with probable causes, and recommended actions to correct the difficulty. 5.
Section 5: Troubleshooting 5.6 TROUBLESHOOTING GUIDE Problems with the NPB-190 are separated into the categories indicated in Table 5-1. Refer to the paragraph indicated for further troubleshooting instructions. Note: Taking the recommended actions discussed in this section will correct the majority of problems you will encounter. However, problems not covered here can be resolved by calling Mallinckrodt Technical Services or your local representative.
Section 5: Troubleshooting 5.6.1 Power Power problems are related to AC and/or DC. Table 5-2 lists recommended actions to power problems. Table 5-2: Power Problems Condition Recommended Action 1. Ensure that the NPB-190 is plugged into an operational AC 1. BATTERY LOW outlet and the AC indicator is on. indicator lights steadily while NPB2. Check the fuses. The Power Entry Module contains the 190 is connected to fuses as indicated in paragraph 6.
Section 5: Troubleshooting 5.6.2 Buttons Table 5-3 lists symptoms of problems relating to nonresponsive buttons and recommended actions. If the action requires replacement of a PCB, refer to Section 6, Disassembly Guide. Table 5-3: Button Problems Condition Recommended Action 1. The NPB-190 responds to some, but not all buttons. 1. Replace Top Housing assembly. 2. The NPB-190 turns on but does not respond to any of the buttons. 1. Check the connection between the membrane panel and J5 of the UIF PCB.
Section 5: Troubleshooting Table 5-4: Display/Alarms Problems (cont. from page 5-4) Condition Recommended Action 5. Alarm does not sound. 1. Check speaker connection to UIF PCB. 2. Replace the speaker as described in Section 6, Disassembly Guide. 3. If the condition persists, replace the UIF PCB. Table 5-5 lists symptoms of problems relating to operational performance (no error codes displayed) and recommended actions.
Section 5: Troubleshooting 5.6.5 Serial Port Table 5-6 lists symptoms of problems relating to the serial port and recommended actions. If the action requires replacement of the PCB, refer to Section 6, Disassembly Guide. Table 5-6: Serial Port Problems Condition Recommended Action 1. No printout is being received. 1. The unit is running on battery power. Connect to an AC source. If the AC indicator is not on see section 5.6.1. 2. The monitor’s baud rate does not match the printer.
Section 5: Troubleshooting 5.7 ERROR CODES An error code will be displayed when the NPB-190 detects a non-correctable failure. When this occurs, the unit will stop monitoring, sound a low priority alarm that cannot be silenced, clear patient data from the display, and display an error code. Error codes will be displayed with EEE in the Saturation display and the number of the code in the Pulse Rate display, i.e., EEE 1. Table 5-7 provides a complete list of error codes and possible solutions.
SECTION 6: DISASSEMBLY GUIDE 6.1 Introduction 6.2 Prior to Disassembly 6.3 Fuse Replacement 6.4 Monitor Disassembly 6.5 Monitor Reassembly 6.6 Battery Replacement 6.7 Power Entry Module (PEM) Removal/Installation 6.8 Power Supply Removal/Installation 6.9 Display PCB Removal/Installation 6.10 UIF PCB Removal/Installation 6.11 Alarm Speaker Removal/Installation 6.
Section 6: Disassembly Guide 6.3 FUSE REPLACEMENT 1. Complete the procedure in paragraph 6.2. 2. Disconnect the power cord from the back of the monitor. 3. Remove the fuse drawer from the Power Entry Module by pressing down on the tab in the center and pulling the drawer out as shown in Figure 6-1. Figure 6-1: Fuse Removal 4. 6-2 Put new 0.5 amp fuses in the drawer and reinsert the drawer in the power module.
Section 6: Disassembly Guide 6.4 MONITOR DISASSEMBLY Caution: Observe ESD (electrostatic discharge) precautions when disassembling and reassembling the NPB-190 and when handling any of the components of the NPB-190. 1. Set the NPB-190 upside down, as shown in Figure 6-2. Corner screws Figure 6-2: NPB-190 Corner Screws 2. Remove the four corner screws. 3. Turn the unit upright. Separate the top case from the bottom case of the monitor being careful not to stress the wire harnesses between the cases.
Section 6: Disassembly Guide J6 Power supply harness Figure 6-3: Separating Case Halves 6.5 MONITOR REASSEMBLY 1. Place the two halves of the monitor on the table as shown in Figure 6-3 and connect the Power Supply to J6 on the UIF PCB. 2. Place the top case over the bottom case and align the four outside screw posts and close the monitor. Caution: When reassembling the NPB-190, hand tighten the screws that hold the cases together to a maximum of 10 inch-pounds.
Section 6: Disassembly Guide 6.6 BATTERY REPLACEMENT Removal 1. Follow procedure in paragraphs 6.2 and 6.4. 2. Remove the two screws from the battery bracket shown in Figure 6-4 and lift the battery out of the bottom case. Use needle-nose pliers to disconnect the leads from the battery. 3. Figure 6-4: Battery Removal 4. The lead-acid battery is recyclable. Do not dispose of the battery by placing it in the regular trash.
Section 6: Disassembly Guide 8. 6.7 Turn the monitor on and verify proper operation. POWER ENTRY MODULE (PEM) REMOVAL/INSTALLATION Removal 1. Complete the procedure in paragraphs 6.2 and 6.4. 2. While pushing the top of the PEM in from the outside of the case, gently push the case to the outside and lift up on the PEM. 3. Use needle-nose pliers to disconnect the leads from the PEM (see Figure 65). G N L Figure 6-5: Power Entry Module Installation 6-6 4. Reconnect the three leads.
Section 6: Disassembly Guide 6.8 6. Position the ground line from the PEM so that it does not come into contact with components on the Power Supply PCB. 7. Complete procedure in paragraph 6.5. POWER SUPPLY REMOVAL/INSTALLATION Removal 1. Complete the procedure described in paragraphs 6.2 and 6.4. 2. Disconnect the leads from the battery. 3. Follow the procedure in paragraph 6.7, steps 2 and 3. 4.
Section 6: Disassembly Guide Figure 6-7: Power Supply Installation 7. Reconnect the AC leads. The wire from the Power Supply labeled “N” goes to the terminal labeled “N” on the PEM. The wire from the power supply labeled “L” connects to the terminal labeled “L” on the PEM. 8. Place the Power Supply in the bottom case. Caution: When installing the Power Supply, tighten the seven screws to a maximum of 10 inch-pounds. Overtightening could strip out the inserts in the bottom case, rendering them unusable.
Section 6: Disassembly Guide 6.9 DISPLAY PCB REMOVAL/INSTALLATION Removal 1. Complete the procedure described in paragraphs 6.2 and 6.4. 2. Lift the Display PCB up to remove it from the top case (Figure 6-8). Grounding clip J4 Figure 6-8: Display PCB Installation 3. Slide the Display PCB into the grooves in the top case, being careful to align the male pins from the Display PCB to connector J4 on the UIF PCB. 4. Complete the procedure in paragraph 6.5.
Section 6: Disassembly Guide 6.10 UIF PCB REMOVAL/INSTALLATION Removal 1. Complete the procedure described in paragraphs 6.2 and 6.4. 2. Lift the Display PCB up to remove it from the top case (Figure 6-8). 3. Disconnect the keypad ribbon cable from J5 of the UIF PCB (Figure 6-8). J5 is a ZIF connector, lift up on the outer shell until it clicks, then remove the ribbon cable from the connector. 4. Disconnect the speaker cable from J3 of the UIF PCB. 5.
Section 6: Disassembly Guide Installation Caution: When installing the UIF PCB, hand-tighten the five screws to a maximum of 10 inch-pounds. Overtightening could strip out the inserts in the top case, rendering them unusable. 7. Place the UIF PCB in the top case. 8. Install the five screws in the UIF PCB. 9. Lift up on the outer shell of J5 on the UIF PCB until it clicks. Insert the keypad ribbon cable into J5 of the UIF PCB. Slide the outer shell of J5 down until it clicks. 10.
Section 6: Disassembly Guide Connect speaker wires to J3 connector Figure 6-10: Alarm Speaker Installation 6-12 4. Slide the speaker into the plastic holding clip provided in the top housing. 5. Connect the speaker wire harness to J3 on the UIF PCB. 6. Complete the procedure paragraph 6.5.
SECTION 7: SPARE PARTS 7.1 Introduction 7.1 INTRODUCTION Spare parts, along with part numbers, are shown below. Item numbers correspond to the numbers called out in Figure 7-1. Item 1 2 3 4 5 6 7 8 9 Description Top Case Assembly (Membrane Panel Included) Fuse Drawer Fuses Power Entry Module Power Supply Display PCB Battery Battery Bracket UIF PCB Sensor Lock (not shown) Alarm Speaker (not shown) Ground Clip (not shown) Rubber Feet (not shown) Power Cord (not shown) Part No.
Section 7: Spare Parts 1 NP B1 90 9 2 3 8 4 7 5 6 Figure 7-1: NPB-190 Exploded View 7-2
SECTION 8: PACKING FOR SHIPMENT 8.1 General Instructions 8.2 Repacking in Original Carton 8.3 Repacking in a Different Carton To ship the monitor for any reason, follow the instructions in this section. 8.1 GENERAL INSTRUCTIONS Pack the monitor carefully. Failure to follow the instructions in this section may result in loss or damage not covered by the Mallinckrodt warranty.
Section 8: Packing for Shipment Figure 8-1: Repacking the NPB-190 8-2 2. Place in shipping carton and seal carton with packaging tape. 3. Label carton with shipping address, return address and RGA number.
Section 8: Packing for Shipment 8.3 REPACKING IN A DIFFERENT CARTON If the original carton is not available, use the following procedure to pack the NPB-190: 1. Place the monitor in a plastic bag. 2. Locate a corrugated cardboard shipping carton with at least 200 pounds per square inch (psi) bursting strength. 3. Fill the bottom of the carton with at least 2 inches of packing material. 4. Place the bagged unit on the layer of packing material and fill the box completely with packing material. 5.
SECTION 9: SPECIFICATIONS 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.1 General Electrical Physical Characteristics Environmental Alarms Factory Default Settings Performance GENERAL Designed to meet safety requirements of: UL 2601-1 CSA-C22.2 No. 601-1-M90, IEC 601-1 (Class I, type BF) EMC per EN60601-1-2 9.2 ELECTRICAL Protection Class Class I: per IEC 601-1, clause 2.2.4 Degree of Protection Type BF: per IEC 601-1, clause 2.2.
Section 9: Specifications 9.3 9.4 PHYSICAL CHARACTERISTICS Dimensions 3.3 in H x 10.4 in W x 6.8 in D 8.4 cm H x 26.4 cm W x 17.3 cm D Weight 5.5 lb 2.5 kg ENVIRONMENTAL Operating Temperature 5°C to 40°C (+41°F to +104°F) Storage Temperature Boxed -20°C to +70°C (-4°F to +158°F) Unboxed -20°C to +60°C (-4°F to +140°F) Operating Atmospheric Pressure Relative Humidity 9.5 700 hPa to 1060 hPa (20.65 inHg to 31.27 inHg) 15% RH to 95% RH, noncondensing ALARMS Alarm Limit Range 9.
Section 9: Specifications 9.7 PERFORMANCE Measurement Range SpO2: 0–100% Pulse/Heart Rate: 20–250 bpm Accuracy SpO2 Adult: Neonate: 70–100% ± 2 digits 0–69% unspecified 70–100% ± 3 digits 0–69% unspecified Accuracies are expressed as plus or minus “X” digits (saturation percentage points) between saturations of 70-100%. This variation equals plus or minus one standard deviation (1SD), which encompasses 68% of the population.
APPENDIX (SERIAL PORT INTERFACE PROTOCOL) A1 Introduction A2 Enabling the Serial Port A3 Connecting to the Serial Port A4 Real-Time Print Out A5 Nurse call A1 INTRODUCTION When connected to the serial port on the back of the NPB-190, a real-time printout can be obtained. Data lines are printed at 2 second intervals. Column headings will be printed after every 25 lines, or if one of the values in the column heading changes.
Appendix The pin layouts are illustrated in Figure A-1. The conductive shell is used as earth ground. An AMP connector is used to connect to the serial port. Use AMP connector (AMP p/n 747538-1), ferrule (AMP p/n 1-747579-2) and compatible pins (AMP p/n 66570-2). 9 1 10 11 12 13 14 15 2 3 4 5 6 7 8 Figure A-1: Serial Port Pin Layout The serial cable must be shielded. Connectors at both ends of the serial cable must have the shield terminated to the full 360 degrees of the connector’s metal shell.
Appendix A4.1 Column Headings NPB-190 Time Tag Version 1.0.0 CRC XXXX %SpO2 PR (bpm) SpO2 Limit: 30-100% PA Status PR Limit: 100-180 bpm To explain the printout, it will be necessary to break it down to its key components. The first two lines of the chart are the column headings shown above. Every 25th line will be a column heading. A column heading is also printed whenever a value of the column heading is changed. There are three column heading lines shown in Figure A-2.
Appendix A4.2 Patient Data and Operating Status Time Tag Time Tag 123456789 %SpO2 100 PR (bpm) 120 PA 220 Status Time Tag does not represent a real-time clock. The number beneath the Time Tag heading represents time, in seconds, since the unit was initialized at the factory. This number will increase in size throughout the life of the monitor. Patient Data NPB-190 Time Tag 123456795 Version 1.0.
Appendix A5 NURSE CALL A Nurse Call signal can be obtained by connecting to the serial port. This function is only available when the instrument is operating on AC power. Nurse Call will be disabled when the unit is operating on battery power, or if the audible alarm is turned off or silenced. The remote location will be signaled anytime there is an active audible alarm. Pin 11 on the serial port is the Nurse Call signal and pin 10 is ground (see Figure A-1).
TECHNICAL SUPPLEMENT S1 Introduction S2 Oximetry Overview S3 Circuit Analysis S4 Functional Overview S5 AC Input S6 Power Supply PCB S7 Battery S8 User Interface PCB S9 Front Panel Display PCB and Controls S10 Schematics S1 INTRODUCTION This Technical Supplement provides the reader with a discussion of oximetry principles and a more in-depth discussion of NPB-190 circuits. A functional overview and detailed circuit analysis is supported by block and schematic diagrams.
Technical Supplement S2.1 Functional Versus Fractional Saturation The NPB-190 measures functional saturation, that is, oxygenated hemoglobin expressed as a percentage of the hemoglobin that is capable of transporting oxygen. It does not detect significant levels of dyshemoglobins. In contrast, hemoximeters such as the IL482 report fractional saturation, that is, oxygenated hemoglobin expressed as a percentage of all measured hemoglobin, including measured dysfunctional hemoglobins.
Technical Supplement S3 CIRCUIT ANALYSIS The following paragraphs discuss the operation of each of the printed circuit boards within the NPB-190 pulse oximeter. (Refer to the appropriate schematic diagram at the end of this supplement, as necessary.) S4 FUNCTIONAL OVERVIEW The monitor functional block diagram is shown in Figure S4-1. Most of the functions of the NPB-190 are performed on the UIF PCB. Functions on the UIF PCB include the SPO2 module, PIC, CPU, and Memory.
Technical Supplement S6 POWER SUPPLY PCB THEORY OF OPERATION The NPB-190 uses an unregulated linear power supply. This power supply provides the DC power needed to charge the battery and to power the User InterFace PCB (UIF). Electro Static Discharge (ESD) protection is also provided by the power supply. AC power from the PEM is passed through a step-down transformer, T2, which has two primary and two secondary windings.
Technical Supplement S7 BATTERY A lead-acid battery is used in the NPB-190. It is rated at 6 VDC 4 amphours. When new and fully charged, the battery will operate the monitor for 12 hours. A new battery will last 15 minutes from the time the low battery alarm is declared until the unit is shut down due to battery depletion. The battery can withstand 400 charge/discharge cycles. Recharging the battery to full capacity takes 14 hours.
Technical Supplement monitor until it is turned off. Default values will be restored when the unit is power-on again. Patient data is stored by the NPB-190 and can be downloaded to a printer through the serial port provided on the back of the monitor. An in-depth discussion of the serial port is covered in the Appendix of this manual. PIC Primary responsibilities of the PIC include monitoring and controlling the NPB190ís power, and generating sounds.
Technical Supplement At initialization of transmission, the LED’s intensity level is based on previous running conditions, and the transmission intensity is adjusted until the received signals match the range of the A/D converter. If the LEDs reach maximum output without the necessary signal strength, the PWMs will increase the channel gain. The PWM lines will select either a change in the LED current or signal gain, but will not do both simultaneously.
Technical Supplement S8.7 AC Ranging In order to achieve a specified level of oxygen saturation measurement and to still use a standard type combined CPU and A/D converter, the DC offset is subtracted from each signal. The DC offsets are subtracted by using an analog switch to set the mean signal value to the mean of the range of the A/D converter whenever necessary. The AC modulation is then superimposed upon that DC level. This is also known as AC ranging.
Technical Supplement S10 SCHEMATIC DIAGRAMS The following schematics are included in this section: Figure Description S-3 Front End Red/IR Schematic Diagram S-4 Front End LED Drive Schematic Diagram S-5 Front End Output Schematic Diagram S-6 Front End Power Supply Schematic Diagram S-7 Isolation Barrier EIA-232 Port Schematic Diagram S-8 CPU Core Schematic Diagram S-9 PIC and Speaker Schematic Diagram S-10 Indicator Drive Schematic Diagram S-11 Core Power Supply Schematic Diagram S-12
VREF I12 VREF 14 1 3 I11 2 U6 74HC00S 7 C22 0.01U AD822 BYPASS +10V VREF I13 U6 74HC00S I14 14 C19 0.01U 4 IRLED/AV 6 5 VCC PWM2 7 I16 I15 U1 C21 0.01U C20 0.01U TP5 I3 R10 88.7K_0.1% VCC 14 X 15 Y 4 7 R6 2.00K U4 AD822 + I2 2 R7 51.1K 3 -5V 1 + 2 1 Z0 Z1 5 3 VSS VREF RED CHANNEL C7 TP10 0.1U Z5U I9 G_REDDC I10 VCC VREF R12 I25 C24 100K 220P R16 82.5K I7 +10V C23 1000P 2 Q7 2N3906S 1 3 1.00K R77 13 + TP6 6 R11 3.32K V+ 7 5 6 +10V GND C1 0.
+10V VREF U5 AD822 C36 390P 5 + 6 - 8 7 4 +10V I27 I28 -5V U12 DG201S 13 V+ 16 R25 3.32K 15 I30 14 R29 1.00M G_LEDDR GND V5 4 I31 C34 -5V 18P IR/RED R27 280K +10V R21 3.32K R28 182K I33 8 VREF VCC C35 0.047U +3 1 U5 AD822 IR/RED VCC C8 0.1U Z5U - 2 4 R37 511K R35 10.0K I35 I46 1 C37 0.047U I47 3 Q10 MPSA56S I32 J1 LED DRIVE R44 2.74K 2 I34 -5V C33 0.01U I37 VCC U2 6 6 11 10 9 VREF 10 R20 10.0K 5 9 4 8 3 7 2 6 1 12 13 I36 R18 2.
I57 I56 I55 ZERO-L REDDC G_REDDC R51 3.32K C55 0.01U R49 3.32K R45 100K DG201S BYPASS 0.015U Guard Ring CK06 +5.7V U9 LMC6044S VREF 2 15 GNDV5 U13 DG201S C46 1000P I54 +5.7V U9 TP20 LMC6044S C6GUARD 12 4 13 -5V R56 15.0K VCC C45 0.01U I59 C52 0.01U I61 VCC R54 34.8K I62 4 1 2 INH A B C 12 13 XO X1 11 R50 3.32K C44 0.01U I70 2 1 Y0 Y1 5 3 Z0 Z1 I63 C57 22U 20V V- GND 4 5 3 V- GND U13 DG201S 4 5 U13 DG201S 7343 -5V -5V -5V U3 6 11 10 9 14 - C53 0.
VDD I41 T1 LPE-4841 I84 1 3 CR10 1N914S C62 1000P 5% 1 C11 0.1U Z5U I73 4 VC S/S 6 GNDS 7 GND VIN VSW FB C61 330P I75 U14 1 5 8 2 I76 VSW VFB + C63 47U 10V 7343 C10 0.1U Z5U 22 C60 10U 16V 2 1 R64 49.9 3 5 I78 2 LT1373S I85 4 I79 VIN C67 22U 20V CURRENT CR9 MBRS130 + R63 11.5K 1 1 78L05D C12 0.1U Z5U + C68 22U 20V 7343 C65 47U 10V 7343 TP16 +5.7V C70 22U 20V + R70 10.
VDD CLKDRV1 L21 T2 SCHOTT 67129080 1 6 600R 2 4 I238 8 TH I237 CR12 1N914 6 2 3 3 3 4 AC V+ T1DIN T2DIN 5 6 R1LDR R2LDR 7 BYP 14 RXDIN ISO_GND V- 2 VPLUS 13 VMINUS RTRI 8 R2IN R1IN 9 10 CR16 BAV99 CR13 BAV99 CR14 BAV99 CR15 BAV99 MAX250S U16 4N26 RXD232 T2OUT 11 T1OUT 12 TXDOUT + C74 4.7U 35V NCALOUT IGND TP24 6 4 2 TH C76 Z5U 0.1U 16 1 9 2 10 3 11 4 12 5 13 6 14 7 15 8 GND 7 R72 10.
VDD 4700P 1 2 196PWR I100 L6 3 4 + 50V C79 470P C102 47U 10V 7343 VDD R117 2.21K I103 I105 ADDRESS LATCHING I107 U27 1 VREF I102 L7 0.95U L8 0.95U L9 0.95U I104 I106 I101 LEDDIS IR/RED REDDC REDAC IRDC IRAC RSENS BTN_1 BTN_2 BTN_3 RWD_RST L10 0.95U L11 0.95U L12 0.95U L13 PORTSEL-L 0.
VDD PICPWR PICPWR 1 PWR_STATUS 2 3 4 I189 RP3 8 7 6 5 PICPWR 10K U22 2 PICINT 3 RST-L EXCOM-SHTDWN 4 5 6 PICEN_L 7 9 OSC1 10100 OSC2 I186 R95 Y3 9.83MHZ 1 2 20 1 8 19 PICPWR HC49S I187 Y4 9.
PICPWR CR19 1N914S I205 R129 10.0K PWRIND-L 1 R94 4.75K 2 2N3906S Q15 1 CR21 1N914S 3 VDD I207 I206 ACIND_L 3 1 VREFVDD PICPWR R97 249 R90 10.0K AC LED DRIVE CIRCUIT PWR_BTN RPWR_IND RBATT_IND BTN_4 BTN_1 VDD R82 4.75K 2 2N3906S Q12 AL_SIL_IND 1 3 I208 I209 R103 249 RP4 10K 1 2 3 4 RPWR_IND R85 10.0K 8 7 6 5 3 RPSRCH_IND BTN_2 BTN_5 BTN_3 RAL_SIL_IND J5 1 2 3 4 5 6 7 8 9 10 11 12 13 CON_FLEX13 MEMBRANE PANEL CONNECTOR RAL_SIL_IND ALARM SILENCE INDICATOR DRIVE CKT VDD R83 4.
TP13 CR17 2 1 MAIN_OUT VDD 1 1 CR24 1N914S U33 MIC5200-5 I240 R112 20.0K 1 R135 100K R139 100K VDD 3 VDD PICPWR TP1 MAIN_DC1 MBRS330T3 C109 1U 35V + 2 CR26 1 3 R115 10.0M I215 OUT 3 IN PICPWR GND1 GND2 2 C108 10U 16V + 4 C111 0.1U R134 10.0K 1N914S J6 + I180 MAIN_OUT 4 3 2 1 R140 10.0K R116 10.
NELLCOR PURITAN BENNETT NPB-190 MAIN TOP SIDE FAB 035190 REV A NELLCOR PURITAN BENNETT NPB-190 MAIN BOTTOM SIDE TOP SIDE BOTTOM SIDE Figure S-12 Parts Locator Diagram for UIF PCB (10 of 10) 035192 S-29
VDD + C2 47U 10V TH U1 C1 19 0.1U TH 18 J1 C3 1000P TH 1 3 5 7 9 11 13 GND TP1 DIG0 DIG1 DIG2 DIG3 DIG4 DIG5 DIG6 DIG7 R9 33.
NELLCOR PURITAN BENNETT NPB-190 DISPLAY TOP SIDE 035196 Figure S-14 Parts Locator Diagram for Display PCB (2 of 2) S-33
LINE_IN C1 220P 250V TH 5 F2 8 8 EPS2PC3 TH 10 + FAC2ASB TH OB24-9 TH NEUT_IN R5 1.00K C5 1/2W 15000U TH 35V TH 3 R19 1.00K 2 To Fan 1 CON_2L 1 CR5 22V SMCJ22C AC- R2 100M TH 1/4W Power Entry C7 0.1U 3 R4 499 CR1 1N4702 15V TH 2 4 1 13 12 2 4 3 6 J1 Q5 MPSA56 2 2 6 Fan Control I11 1 3 230V T1 E3490A TH I10 1 7 9 E 2 C6 0.
"N" "GND" NELLCOR PURITAN BENNETT NPB-190 LPS TOP SIDE "L" "-" "+" 035200 Figure S-16 Parts Locator Diagram for Power Supply PCB (2 of 2) S-37
