Download Spiro USB Service Manual - Frank`s Hospital Workshop

Spiro USB
Service Manual
075-12
Revision 1.0 February 2004
Micro Medical Limited, P.O. Box 6, Rochester, Kent ME1 2AZ
1
Spiro USB - System Overview (Fig. 1)
The Spiro USB is a PC connected spirometer dedicated to work w ith SPIDA 5
spirometry software.
It consists of a removable digital volume transducer (1) and a housing (2) containing
a microprocessor control circuit and USB driver.
When testing a subject the transducer is inserted into the housing, which is plugged
into a USB socket of a PC. The digital volume transducer is used to measure the
subjects expired flow and volume in accordance with the operating manual.
1
2
2
Transducer (Fig. 2)
The Micro Medical digital volume transducer consists of an acrylic tube with a
vane positioned between two swirl plates. The low inertia vane is attached to a
stainless steel pivot which is free to rotate on two jewelled bearings mounted at the
centre of the swirl plates. As air is passed through the transducer a vortex is created
by the swirl plates which causes the vane to rotate in a direction dependant upon the
direction of air flow. The number of rotations is proportional to the volume of air
passed through the transducer and the frequency of rotation is proportional to the
flow rate. The transducer housing consists of a main body which contains a pair of
light emitting diodes (LED’s) and phototransistors. The transducer is fixed to the
mouthpiece holder which pushes into the main body and is captured by an “O” ring
seal. The LED’s produce infra red beams which are interrupted by the vane twice
per revolution. This interruption is sensed by the phototransistors. The output from
the collector of each phototransistor will be a square wave with a phase difference
between the two of + or - 90 degrees depending upon the direction of flow.
There is no routine maintenance required for the transducer other than cleaning
according to the instructions in the operating manual.
Micro Medical Digital Volume Transducer
Rotating
vane
Infra red
emitter
Swirl
plate
Jewelled
bearing
Infra red
detector
Volume = k X No. of pulses
Volume proportional to the number of pulses
Flow proportional to the puse frequency
Flow = k / pulse period
3
Disassembly (Fig. 3)
1. Carefully remove both Spiro USB labels from the transducer housing.
2. Remove the screw under each label.
3. Pull apart the two halves of the housing as shown below:
Reassembly (Fig. 4)
Please note: Do not use excessive force when reassembling.
1. Ensure the PCB is aligned correctly as shown in Fig. 4.
2. Pull the cable gland through the hole in housing A (already on the cable) and
locate the centre moulding into the housing.
3. Line up the channel on the centre moulding with the screw hole of housing A.
4. When refitting housing B, locate the moulded bracket (with the nut) between
the end of the channel and housing A and carefully pivot housing B around
until the two housings meet (ensuring the blue LED fits into it’s hole).
5. Replace the screws.
6. Carefully reposition the Spiro USB labels.
4
The PCB, LED’S and phototransistors will be accessible as shown below:
Fig. 4.
Channel
Centre moulding
5
Microprocessor control circuit, see drawing 075-01 and 075-02
The microprocessor control circuit monitors the transducer pulses, carries out the
spirometry routines, and communicates with the PC via a USB driver under the
control of it’s internal program.
Power for the processor circuit is derived from the 5 volt USB power line. The power
line is filtered by C12, L1 and C13. The filtered 5 volt is regulated down to 3.3 v olts
by the linear regulator, U7. U7 also provides a reset signal for the microprocessor.
The microprocessor, U3, is a Hitachi HD64F2318 16 bit microprocessor with 256K of
flash memory and 8K of Ram. The system clock is supplied by 12MHz crystal, X1.
There is also 512 Kbytes of external RAM, U8, used for storing pulses during a
spirometry manoeuvre. The internal flash memory is used to store the
microprocessor firmware.
Calibration data and system data is stored in an EEPROM, U2. Communication to
the EEPROM is carried out using a two wire serial connection to pins 54 and 55 of
the microprocessor. If the device is ever replaced, the unit will have to undergo
factory recalibration.
Ambient temperature is monitored by a solid-state temperature sensor, U9. It
communicates with the microprocessor via a one wire serial interface on pin 90.
The ambient temperature reading is used for adjusting inspiratory volume at ambient
temperature to volume at body temperature.
The supply to the two series LED’s, mounted inside the transducer housing, is
provided through TR1, which is switched on by pin 4 of the microprocessor during a
spirometry manoeuvre. Inside the transducer housing the two phototransistors used
to detect the interrupted infra-red beam are in open collector configuration. The pull
up resistor for the two phototransistors is provided by R7 and R8.
Pulses from the phototransistor, TR2, are applied to the pulse timing input of the
processor, pin 5, after being squared up by the action of the Schmitt i nverter, U4.
Pulses from the second phototransistor, TR3, after conditionings, U5, are applied to
pin 6 of the microprocessor and are used to determine the direction of flow. The
pulse count is used to determine the volume passed through the transducer since
the start of the test and the pulse period is used to determine the flow at each
volume increment.
The microprocessor communicates with the host PC via a USB interface, U6. U6 is
connected to the microprocessor data bus and one address line, A0.
The 512k x 8 static RAM, U8, is located on the underside of the PCB and
communicates with the processor on the 19-bit address bus and 8-bit data bus.
The speaker, J1, is directly connected to ports on pins 91 and 92 that are toggled at
1 KHz to generate the sound.
6
Drawing No.
075-00
Revision No. 1.4
Designation
Part No.
Date 07/01/04
Page: 1 OF 3
Description.
U1
U2
U3
U4
U5
U6
U7
U8
U9
TR1
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R13
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
L1
X1
LED
LED2
LED3
TR2
TR3
Individual CMOS Schmitt NAND gate
128 bit serial EEPROM
Hitachi microcontroller
Individual CMOS Schmitt inverter
Individual CMOS Schmitt inverter
USB interface
3V3 regulator with integrated RESET
512k X 8 bit CMOS static RAM,
Digital thermometer
NPN digital transistor
100K resistor 1%
100K resistor 1%
180 Ohm resistor 1%
10K resistor 1%
10K resistor 1%
1K resistor 1%
4.7K resistor 1%
4.7K resistor 1%
22 Ohm resistor 1%
22 Ohm resistor 1%
1.5K resistor 1%
120 Ohm resistor 1%
100K resistor 1%
33pF ceramic capacitor
33pF ceramic capacitor
100nF ceramic capacitor
100nF ceramic capacitor
100nF ceramic capacitor
100nF ceramic capacitor
1nF ceramic capacitor
1nF ceramic capacitor
100nF ceramic capacitor
100nF ceramic capacitor
4.7uF ceramic capacitor
100nF ceramic capacitor
1uF ceramic capacitor
220nH inductor
12MHz crystal
Blue LED
Infra red LED
Infra red LED
Infra red photo transistor
Infra red photo transistor
BU4S11
24LC00-OT
HD64F2318VTE25
BU4S584
BU4S584
SL811HST
MAX6349TL
K6X4008T1F-VF70
DS18S20
DTD113EK
LQW18ANR22G00D
L934MBC
SEP8705
SEP8705
SDP8405
SDP8405
7
1
2
3
4
5
6
7
8
VCC
VCC
5V
CON1
R1
100K
VCC
U7
1
1
2
3
4
5
TX
RX
VCC
OUT
6
MODE
5
IN
2
D
GND SET
3
/MR /RST
5
10UF/6V3
4 RESET-
C10
0.1uF
C9
0.1uF
C6
0.1uF
C5
0.1uF
C4
0.1uF
U1
+
C11
FWE
D
1
PROGRAMMING PORT
VCC
VCC
4
2
MAX6349SL
3
BU4S11
R13
100K
5V
U9
L1
C12
0.1UF
1
2
3
TEMP_SEN
220nH
C13
1UF
X1
12MHz
C2
C1
VDD
DQ
GND
DS18S20
VCC
33pF
33pF
VCC
5
DACKM/S
CM
D0
D1
D2
D3
D4
D5
D6
D7
U6
SL811HST
Ram
RAM.sch
A[0..18]
D[0..7]
B
A[0..18]
D[0..7]
CSRDWR-
D0
D1
D2
D3
D4
D5
D6
D7
23
24
25
26
27
28
29
30
A0
A1
A2
A3
A4
A5
A6
A7
32
33
34
35
36
37
38
39
A8
A9
A10
A11
A12
A13
A14
A15
41
42
43
44
45
46
47
48
A16
A17
A18
50
51
52
53
99
100
1
2
69
70
71
72
73
74
75
76
97
96
95
94
93
PD0/D8
PD1/D9
PD2/D10
PD3/D11
PD4/D12
PD5/D13
PD6/D14
PD7/D15
PC0/A0
PC1/A1
PC2/A2
PC3/A3
PC4/A4
PC5/A5
PC6/A6
PC7/A7
PB0/A8
PB1/A9
PB2/A10
PB3/A11
PB4/A12
PB5/A13
PB6/A14
PB7/A15
PA0/A16
PA1/A17
PA2/A18
PA3/A19
P10/A20
P11/A21
P12/A22
P13/A23
5V
57
58
61 MODE
60 FWE
VCC
R3
1K
C
1
TIMER_A 4
2
P30/TXD0
P32/RXD0
P34/SCK0/IRQ4
P31/TXD1
P33/RXD1
P35/SCK1/IRQ5
P14/TIOCA1
P15/TIOCB1/TCLKC
P16/TIOCA2
P17/TIOCB2/TCLKD
P20/TIOCA3
P21/TIOCB3
P22/TIOCC3/TMRI0
P23/TIOCD3/TMCI0
P24/TIOCA4/TMRI1
P25/TIOCB4/TMCI1
P26/TIOCA5/TMO0
P27/TIOCB5/TMO1
P40/AN0
P41/AN1
P42/AN2
P43/AN3
P44/AN4
P45/AN5
P46/AN6/DA0
P47/AN7/DA1
AVCC
VREF
PF7/CLK
PF6/AS
PF5/RD
PF4/HWR
PF3/LWR/IRQ3
PF2/WAIT/IRQ2
PF1/IRQ1/CS5
PF0/IRQ0/CS4
AVSS
8
10
12
C7
BU4S584
9
11
13
TR2
TDET500C LED3
TEMT1288C
1nF
LED
LED
TX
RX
Note:
LED2, LED3, TR2 and TR3
3
4
5
6
are external components.
54
55
56
59
89
90
91
92
VCC
VCC
TEMP_SEN
1
2
R6 1K0 BUZZER J1
79
80
81
82
83
84
85
86
R8
4K7
U5
1
B
LED2
TEMT1288C
TR3
TDET500C
4
DIR
2
BU4S584
C8
1nF
VCC
77
78
87
VCC
VCC
R5
10K
TR1
DTD113EK
1
R4
10K
VCC
U2
PG4/CS0
PG3/CS1/CS7
PG2/CS2
PG1/CS3/IRQ7/CS6
PG0/IRQ6
SCL
1
2
SDA
3
HD64F2318VTE25
A
R7
4K7
U4
1
16
D0
D1
D2
D3
D4
D5
D6
D7
DRQ-
21
27
28
29
31
32
33
39
MD0
MD1
MD2
FWE
3
40
IRQ
42
VCC
2
43
A0
R12
120R
RESET-
2
44
D-
4
45
3
18
1
19
CSRDWRRST-
2
8
USB_CON
D+
66
67
62
64
63
5
7
XTAL
EXTAL
RES
STBY
NMI
5V
R2
100K
VCC
PE0/D0
PE1/D1
PE2/D2
PE3/D3
PE4/D4
PE5/D5
PE6/D6
PE7/D7
3
R10
22R
U3
14
15
16
17
19
20
21
22
1K5
5
22R
3
R9
X1
1
2
3
4
X2
CON2
C
17
Temperature Sensor
R11
SCL VCC
5
VSS
SDA NC
C3
100nF
4
A
24LC00-OT
Title
Size
USB SPIROMETER
Number
1
2
3
4
5
8
6
Revision
075-01
A3
Date:
File:
12-Feb-2004
G:\Archive\Temp\075-01.sch
7
1.2
Sheet of
Drawn By: Arthur Sadler
8
1
2
3
4
5
6
7
8
D
D
VCC
A[0..18]
D[0..7]
D[0..7]
32
A[0..18]
C
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
12
11
10
9
8
7
6
5
27
26
23
25
4
28
3
31
2
30
1
24
29
22
RDWRCS-
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
VCC
C
D0
D1
D2
D3
D4
D5
D6
D7
OE
WE
CS1
13
14
15
17
18
19
20
21
D0
D1
D2
D3
D4
D5
D6
D7
512K x 8
U8
K6X4008T1F-VB70
B
B
A
A
Title
Size
Spiro USB - Circuit diagram, memory
Number
A3
Date:
File:
1
2
3
4
5
9
6
7
Revision
075-02
12-Feb-2004
G:\Archive\Temp\075-02.sch
Sheet of
Drawn By:
1.0
Arthur Sadler
8