FIC98648 [ETC]
Microprocessor for use with TGS4160 in automatic CO2 monitors; 微处理器自动CO2监测与TGS4160使用
| 型号： | FIC98648 |
| 厂家： | 
ETC |
| 描述： | Microprocessor for use with TGS4160 in automatic CO2 monitors |
| 文件： | 总14页 (文件大小：230K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
TECHNICAL INFORMATION FOR FIC98648
Technical Information for FIC98648--microprocessor for
use with TGS4160 in automatic CO2 monitors
The FIC98648 is a microprocessor
for handling signals from the
TGS4160 carbon dioxide sensor.
This microprocessor enables
maintenance-free automation of
the air quality control in buildings
when connected with appliances
such as ventilation fans, air
cleaning systems, etc.
Page
Introduction.........................................................................................2
Features................................................................................................2
Basic Function...............................................................................................3
Pin Arrangement...........................................................................................3
Pin Functions
Pins for the initial setting of operational conditions....................................3
Gas sensor signal Vg input .........................................................................5
Internal thermistor signal VT input ...........................................................5
Bias signal output......................................................................................5
Manual benchmark reset signal input........................................................5
Sensor signal output....................................................................................5
LED display signal output..........................................................................6
Malfunction signal output.........................................................................6
Benchmark renewal status signal output........................................................6
Line test mode...........................................................................................7
Electrical Circuits for FIC98648........................................................................7
Hardware Specifications....................................................................................12
IMPORTANT NOTE: OPERATING CONDITIONS IN WHICH FIGARO SENSORS ARE USED WILL VARY
WITH EACH CUSTOMER’S SPECIFIC APPLICATIONS. FIGARO STRONGLY RECOMMENDS
CONSULTING OUR TECHNICALSTAFF BEFORE DEPLOYING FIGARO SENSORS IN YOURAPPLICATION
AND, IN PARTICULAR, WHEN CUSTOMER’S TARGET GASES ARE NOT LISTED HEREIN. FIGARO
CANNOT ASSUME ANY RESPONSIBILITY FOR ANY USE OF ITS SENSORS IN A PRODUCT OR
APPLICATION FOR WHICH SENSOR HAS NOT BEEN SPECIFICALLY TESTED BY FIGARO.
Revised 08/03
1
TECHNICAL INFORMATION FOR FIC98648
Introduction
benchmark value is assumed to be equal to the level
of CO2 which exists in ambient air (approx. 400ppm).
The FIC98648 is a microprocessor for handling signals CO2 concentrations are calculated periodically by
from the TGS4160 carbon dioxide sensor, enabling determining the change of EMF from the benchmark
maintenance-free automation of air quality control level (∆EMF). In order to offset the effects of sensor
in buildings when connected with appliances such signal drift which are caused by environmental
as ventilation fans, air cleaning systems, etc.
temperature and air contaminants, the micro-
processor automatically renews the benchmark level
The microprocessor takes in the output voltage, or to the current EMF value whenever a lower CO2
electromotive force (EMF), from the TGS4160 sensor concentration than the current benchmark is
and outputs a signal which corresponds to a calculated. Using this method of automatic calibra-
concentration of CO2 in the environment. CO2 tion, very stable characteristics can be expected for
concentrations are calculated in the microprocessor the sensor, allowing for reliable monitoring of CO2
based on ∆EMF, which is the change in the value of levels and long term maintenance-free ventilation
EMF from the value in a normal clean environment. control.
The microprocessor also contains software to
compensate the sensor’s signal for changes in 1-2 High CO2 sensitivity and wide detectable range of
temperature and basic environmental factors.
1. Features
400~3000ppm
By programming the microprocessor to take into
consideration the unique performance characteristics
of the TGS4160, reliable readings of CO2 concen-
trations within a wide range (400~3000ppm) can be
1-1 Automatic calibration
The FIC98648 uses the concept of a benchmark value achieved, satisfying the requirements of building
of EMF in order to provide automatic calibration. The ventilation control applications.
Input port for +4.4V
X
OUT
1
2
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
DD
X-TAL
Input port for manual
benchmark reset
XIN
KEO
R92
R91
R90
R83
R82
R81
R80
R63
R62
R61
R60
R53
Input port for
microprocessor reset
Output port for benchmark
renewal status signal
RESET
R70
3
Input port for
test mode
Output port for CO
2
4
concentration signal
Output port for
bias signal
5
R71
Input port for +4.4V
Input port for +3.8V
V
AREF
6
GND
GND
Gas sensor signal
input port
AIN0
AIN1
AIN2
R43
7
Thermistor signal
input port
8
GND
GND
Input port for damper
control thresholds
9
Input port for setting
warm up period
Output port for green LED
10
Input port for setting
11 R50
12 R51
13 R52
Output port for red LED
benchmark renewal (V
L)
Input port for setting
benchmark renewal (TK)
Output port for malfunction signal
Output port for damper
control signal
Input port for automatic
benchmark reset (Tr)
14
VSS
GND
GND
Figure 1 - Pin arrangement for FIC98648
Revised 08/03
2
TECHNICAL INFORMATION FOR FIC98648
1-3 Two output signals
4-1 Pins for the initial setting of operational conditions
FIC98648 generates two separate output signals:
To optimize sensor performance, the following pins
a) For calculating CO2 concentrations, a pulse width are provided for setting operational conditions at the
modulated (PWM) signal is output.
time of power-on. No change can be made to
b) An On/Off signal is generated as a control signal operational conditions after the initial setting without
for devices such as ventilation fans, dampers, etc. powering off and then repowering the device.
Notes:
4-1-1 Input signal for setting the sensor’s initial warm-
1) The microprocessor is designed to assume the
up time (Pin No. 10)
highest value of EMF reading is representative of Initial warm-up time, which is necessary to stabilize
400ppm of CO2 (ambient air levels). As a result, an the sensor’s output signal after an unpowered period,
accurate reading cannot be expected if the sensor is is set by input of a signal to port R43 (see Table 2).
used in an environment where CO2 constantly exists No signal can be taken from the microprocessor’s
at higher concentrations than can be found in a output ports during initial warm-up time.
normal clean environment.
Signal Input
2) This device is not suitable for usage in life saving
equipment.
Setting
"H"
"L"
Initial warm-up
time (T1)
2. Basic Functions
30 minutes
120 minutes
2-1 Initial setting of operational conditions
Table 2 - Initial warm-up time setting (AM-4 default = "L")
In order to achieve optimal performance of the sensor,
manual preset of operational conditions is provided. 4-1-2 Input signals VL and TK for benchmark adjustment
(Pins No. 11 and 12)
The benchmark level is normally set at the lowest
2-2 Automatic operation
Once power is supplied, an initial warm-up timer is value of the sensor’s signal (Vg), which is considered
activated. When the initial warm-up time is finished, as 400ppm of CO2 (ambient levels). The benchmark
the microprocessor will automatically begin level Vg is renewed whenever a lower signal voltage
operation and commence generating the two output than the present benchmark level is read from the
signals mentioned above.
sensor (as described in Sec. 1-Automatic calibration).
If the benchmark level Vg is not renewed for a pre-
set period of time (TK), it is automatically adjusted
2-3 Line test
The microprocessor has the ability to perform a line upward by a pre-set voltage (VL) which corresponds
test for checking the functionality of the to an equivalent concentration of CO2. Table 3 shows
microprocessor and the surrounding circuits. This the user-determined settings for VL and TK which
allows users to eliminate tool testing which is can be selected by applying a signal to Ports R50 and
normally done on the production line after assembly. R51 respectively.
Terminal
Signal input
3. Pin Arrangement
Setting
Symbol
Pin No.
"H"
"L"
Benchmark
adjustment level
Pin arrangement of FIC98648 is shown in Figure 1.
4. Pin Functions
5ppm
20ppm
R50
R51
11
equivalent equivalent
(VL)
Benchmark
adjustment time
12
1 day
7 days
(TK)
The basic pin functions of FIC98648 are shown in
Table 1 (shown on Page 4).
Table 3 - Benchmark adjustment level and timer setting
(AM-4 default = 20ppm equiv. and 1 day)
Revised 08/03
3
TECHNICAL INFORMATION FOR FIC98648
Terminal
Category
Functions
Pin
No.
Name
Symbol
Power supply
Ground
VDD
VSS
28 Connect to +4.4V power supply
14 Connect to ground
Power
Connect to 3.8V power supply (Reference voltage for A/D
converter)
Reference voltage
Reset
VAREF
6
Microprocessor reset when "L" is input for one machine
cycle or longer
RESET
3
Microprocessor
control
Clock in
XIN
XOUT
R43
2
Connect to ceramic oscillator of 4.19MHz
(ports to internal clock circuit)
Clock out
1
Initial warm-up time
10
Benchmark adjustment
level (VL)
R50
11
Input optional "H" or "L" signal
See Sec. 4-1 - Pins for initial setting of operation conditions
Settings
Benchmark adjustment
time (TK)
R51
R52
12
Auto reset time
13
Input gas sensor signal (Vg)
See Sec. 4-2 - Gas sensor signal Vg input
Gas sensor signal (Vg)
AIN0
7
Analog signal
input
Thermistor signal (VT) for temperature compensation circuit
See Sec. 4-3 - Internal thermistor signal VT input
Thermistor signal (VT)
Control signal threshold
AIN1
AIN2
KEO
8
Calibration of CO2 levels for damper control
See Sec. 4-1-4 - Input signal for damper control
9
Manual benchmark
reset
Switch input
Signal output
27 See Sec. 4-5 - Manual benchmark reset signal input
Bias signal
R90
R60
24 See Sec. 4-4 - Bias signal output
Damper control signal
16 See Sec. 4-6-2 - Damper control signal output
CO2 concentration
signal
R91
25 See Sec. 4-6-1 - PWM signal output for CO2 concentration
Green LED
R63
R62
R70
R61
19 See Sec. 4-7 - LED display signal output
18 See Sec. 4-7 - LED display signal output
Red LED
Test mode (Input)
Malfunction (Output)
4
See Sec. 4-10 - Line test mode
17 See Sec. 4-8 - Malfunction signal output
Other
Benchmark renewal
status (Output)
R92
26 See Sec. 4-9 - Benchmark renewal status signal output
Table 1 - Pin functions of FIC98648
Revised 08/03
4
TECHNICAL INFORMATION FOR FIC98648
4-1-3 Input signal Tr for automatic benchmark reset (Pin output voltage is reversed, amplified and adjusted
No. 13)
(please refer to Figure 3, Sec. 4-4, and Sec. 5-1 for
Whenever the benchmark level Vg has only been details). The result of this process is a gas sensor signal
adjusted (Sec. 4-1-2) and has not been renewed (Sec. Vg with good resolution and which increases/
1-1) for a pre-set period of time (Tr), it should be auto- decreases as CO2 concentration increases/decreases.
matically reset at the current output signal in ambient This gas sensor signal Vg is input to port AIN0.
air. Table 4 shows the time intervals (Tr) which can
be pre-set by applying a signal to Port R52.
4-3 Internal thermistor signal VT input (Pin No. 8)
To compensate for the temperature dependency of
CO2 sensor, a signal from the sensor’s internal
thermistor (VT) is input to portAIN1. This thermistor
also monitors the sensor’s built-in heater from 30
minutes after powering and after. By detecting a
sharp drop in the sensor’s internal temperature
indicative of a broken heater, the thermistor can cause
a malfunction signal to be generated by the
microprocessor.
Signal Input
Setting
"H"
"L"
Auto reset time
(Tr)
7 days
30 days
Table 4 - Auto reset timer setting (AM-4 default = 7 days)
4-1-4 Input signal for damper control (Pin No. 9)
Concentration levels of CO2 at which the damper
control signals are activated are selected by inputting 4-4 Bias signal output (Pin No. 24)
a voltage signal to port AIN2. Sensor output voltage A PWM signal, of which the pulse width is variable,
is first AD converted within the microprocessor. The is output from port R90. To optimize the resolution
relationship between these AD converted values and of Vg readings, this signal is introduced to the
CO2 concentrations is shown in Table 5. Whenever a differential circuit after being converted to an analog
CO2 concentration exceeds the threshold level for voltage, and adjusts the benchmark level Vg to fall
opening the damper (Cd1), a low signal (L) is output between 25 and 51 counts at AD converted value, or
from port R60. Ahigh signal (H) is output for closing 0.38 ~ 0.75V at 3.8V full scale. The bias signal starts
the damper when the CO2 concentration drops from 128 counts (1.9V at 3.8V full scale) when the
beneath the Cd2 level. Figure 11 shows the circuit power is switched on, and reduces the count stepwise
for damper control signal threshold. Please note that along with the sensor’s initial action until Vg falls
a high signal (H) is designed to be output during the and then stabilizes at the above stated level.
sensor’s initial warm-up period and also whenever
the malfunction signal is activated.
4-5 Manual benchmark reset signal input (Pin No. 27)
The benchmark level can be reset manually at any
time by inputting an “L” pulse to port KEO. This
manual benchmark reset should be done in a clean
atmosphere where the CO2 concentration is about
400ppm (please refer to Sec. 5-6 - Benchmark reset
circuit).
Signal input
Cd1 (ppm)
Cd2 (ppm)
(AD converted: 0-255*)
0 - 48
49 - 96
800
720
800
1000
1500
2000
3000
97 - 144
145 - 192
193 - 255
1300
1800
2700
Note: If the benchmark level is manually reset under
a high CO2 concentration environment, the device’s
sensitivity would be decreased and calculated CO2
concentration values would be less than the actual
concentration.
Cd1: Threshold for OPEN signal
Cd2: Threshold for CLOSE signal
* 8-bit - Least significant byte=3.8V/256
Table 5 - Thresholds for damper OPEN/CLOSE signal
4-6 Sensor signal output
4-2 Gas sensor signal Vg input (Pin No. 7)
Since the raw sensor output voltage (EMF) actually
decreases as CO2 concentration increases, the sensor’s
4-6-1 PWM signal output for CO2 concentration (Pin No. 25)
A PWM signal is output from port R91 to show CO2
Revised 08/03
5
TECHNICAL INFORMATION FOR FIC98648
H
concentration readings. The pulse width against a
cycle corresponds to the CO2 concentration as shown
in Figure 2. This pulse width is then converted to an
analog output voltage between 0 ~ 3V by the circuit
(please refer to Sec. 5-4 - CO2 concentration circuit).
L
A
B
C
A: [(CO
B: C - [(CO
C: approx. 65msec.
2
concentration) / 3000] x C
Approx. 65 msec.
2
concentration) / 3000] x C
4-6-2 Damper control signal output (Pin No. 16)
The output from port R60 is set to “H” under normal
conditions in a clean environment, indicating that the
damper should be closed. When a CO2 reading
exceeds the preset level of the Open Damper
Threshold (Cd1) as shown in Table 2, an “L” signal is
output from port R60 as a signal for opening the
damper. When CO2 drops below the preset level of
the Close Damper Threshold (Cd2), the output from
port R60 returns to an “H” signal for closing a
damper. “H” is also output from port R60 during
initial warm-up time and whenever a malfunction
signal is output.
Figure 2 - PWM signal for CO2 concentration
4-8 Malfunction signal output (Pin No. 17)
An “H” signal is output from port R61 under normal
operation conditions. When a malfunction is detected on
the gas sensor’s heater and/or the benchmark level Vg,
an “L” signal is output from port R61. The following
conditions would generate a malfunction signal:
(a) Sensor heater breakage—when the thermistor’s
signal (VT) remains at a level equivalent to 50°C
or lower for over 10 seconds, the heater can be
considered to have malfunctioned. Monitoring of
this condition commences 30 minutes after
powering on.
(b) Benchmark level Vg malfunction—when the
benchmark level Vg (gas sensor’s signal) cannot
be adjusted in the range between 25 and 51 counts
at AD converted value within 10 minutes after
the adjustment is started, a malfunction is
considered to have occurred.
4-7 LED display signal output (Pin Nos. 18 & 19)
The following LED display signals are output from
port R62 (red LED) and port R63 (green LED):
4-7-1 Initial warm-up time
During the initial warm-up period (see Sec. 4-1-1),
an alternating H/L signal is output from port R63
every 0.5 seconds, causing the green LED to alternate
between on and off every 0.5 seconds. “L” is output
continuously from R62 during this period.
The relationship between signal output ports and
their output signals under malfunction mode can be
seen in Table 6.
4-7-2 Normal operation mode
When the CO2 concentration is lower than the preset
threshold level for the damper control (Cd1), “L” is
output from port R62 and “H” is output from the
R63, causing the green LED to be lit continuously.
Conversely, if the CO2 concentration is higher than
the preset threshold level for the damper control
(Cd1), “H” is output from port R62 and “L” is output
from port R63, causing the red LED to be lit
continuously.
Terminal
Signal
Indication
CO
2 concentration
signal (R91)
“L” signal
0ppm
Damper control
signal (R60)
“H” signal
Close
Alternate H/L signal
(0.5 sec./0.5 sec.)
Red LED (R62)
On/Off
Green LED (R63)
Bias signal (R90)
“L” signal
Off
Off
Hold the level
Table 6 - Malfunction signal
4-7-3 Malfunction mode
4-9 Benchmark renewal status signal output (Pin No. 26)
When the benchmark level has been renewed, an “L”
signal is output from port R92 for one second to
indicate the status. An “H” signal is normally output
from this port.
When a malfunction has been detected (see Sec. 4-8),
an alternating H/L signal is output from port R62
every 0.5 seconds, causing the red LED to alternate
between on and off every 0.5 seconds. “L” is output
continuously from R63 during this period.
Revised 08/03
6
TECHNICAL INFORMATION FOR FIC98648
4-10 Line test mode (Pin No. 4)
shown in Table 7. After powering on, signal outputs
A line test mode can be activated by the input of an change from Step 1 to Step 4 according to the table,
“L” signal to port R70 at the moment of power supply. with Steps 1-3 lasting 5 seconds each. Afterwards,
Operation of the microprocessor and the surrounding Step 4 outputs will be maintained continuously until
circuits will be tested according to the schedule the power is shut off.
Terminal
Symbol
Signal Output
Name
Pin No.
Step 1
Step 2
Step 3
Step 4
CO
2
concentration
signal
Cd1 (ppm)
Note *1
R91
R90
25
Cd1 (ppm)
255
Cd1 (ppm)
Cd1 (ppm)
Bias signal
24
0
128
128
Note *2
Green LED
Red LED
R63
R62
19
18
L
H
L
(Note 3)
(Note 4)
H
H
H
Damper control
signal
R60
R61
R92
16
17
26
H
H
H
L
L
L
(Note 5)
(Note 6)
H
H
H
H
Malfunction
Benchmark
renewal status
Notes:
(1) Please refer to Sec. 4-1-4 - Input signal for damper control
(2) Please refer to Sec. 4-4 - Bias signal output
(3) H or L, as input to Pin #10 for initial warmup setting - refer to Sec. 4-1-1
(4) H or L, as input to Pin #11 for benchmark adjustment - refer to Sec. 4-1-2
(5) H or L, as input to Pin #12 for benchmark adjustment - refer to Sec. 4-1-2
(6) H or L, as input to Pin #13 for benchmark reset - refer to Sec. 4-1-3
(7) Outputs shown are held until power is shut off
Table 7 - Line test mode
5. Electrical Circuit for FIC98648
and Figure 4 (Page 8) respectively. Please note the
following items:
The following peripheral circuits are suggested when a) +5.0V should be applied to Pin No. 6 for the heater
using the FIC98648 with the TGS4160 sensor.
of TGS4160.
b) +3.8V is the specified voltage to sensor pin No. 5
for the built-in thermistor which is connected in
series with an 8.2kΩ resistor. Output voltage across
the 8.2kΩ resistor is designed to be input to port
5-1 Circuit for driving sensor and for processing sensor signals
The block/circuit diagrams for driving the sensor and
processing its signals are shown in Figure 3 (below)
+3.8V
+5V
FIC98648
Heater
voltage
(VH)
Sensor
voltage
(EMF)
4.5 times
amplification
circuit
10 times
amplification
circuit
Thermistor
signal (VT)
Regulation
circuit
Buffer
circuit
+
+
Buffer
circuit
Bias signal (PWM signal)
Convert to DC
Figure 3 - Block diagram for driving sensor and processing sensor signal
Revised 08/03
7
TECHNICAL INFORMATION FOR FIC98648
FIC98648
AIN0
10k
7
10µ
104
220 k
+5V
+3. 8V
TLC271CP
8
22k
3
7
9
6
8
6
2
5
3
4
10
4
LM324N
SENSOR
103
30k
8
2
30k
1
AIN1
R90
100p
10k
8.2k
+4.4V
100k
10k
6
5
24
7
1M
1m
LM324N
47k
104
Figure 4 - Circuit for driving sensor and processing sensor signal
AIN1 (Pin No. 8) as a thermistor signal for the 5-2 Power supply circuit
temperature compensation circuit. As illustrated in Figure 5, the circuit is designed to
c) As a first stage, the sensor’s output (pin No. 3), be operated by +5V. The sensor’s heater, which
which is of very high impedance, should be requires a large current, is powered directly by +5V.
amplified by 4.5 times with a high impedance The microprocessor is powered by +4.4V (down-
(100MΩ or higher) operational amplifier, such as stream from a diode). A diode is connected between
Texas Instrument’s Model No. TLC271. This the power supply and the microprocessor to protect
amplified signal is designed to be further amplified the microprocessor from a surge current. Taking the
by ten times in the second stage. The output from saturation voltage of the operational amplifiers into
the amplifier is input into port AIN0 (Pin No. 7) consideration, the analog reference voltage (VAREF)
after being adjusted by a regulator (differential is set at +3.8V. Voltage is provided downstream from
circuit) with a bias signal.
another diode.
FIC98648
+5V
+4.4V
1SS176
28
VDD
+3.8
V
1SS176
6
VAREF
5V
µ
2. 2k
µ
103
104
220
220
6. 2V
14
VSS
Figure 5 - Power supply circuit
Revised 08/03
8
TECHNICAL INFORMATION FOR FIC98648
5-3 System reset circuit
+4.4V
Under normal operating conditions, an “H” signal is
continuously applied to the RESET port (Pin #3).
When an “L” signal is applied to the RESET port for
a period of one machine cycle or longer, the internal
logic circuit of FIC98648 and the micro-processor’s
program return to the same condition which exists
just after powering on the unit, effectively resetting
the system.
FIC98648
2SA1015Y
28
VDD
1k
104
3
RESET
4. 7 k
3.9k
103
14
VSS
To perform the above described system reset function
automatically, a circuit such as that shown in Figure
6 is suggested. This kind of automatic system reset
circuit is useful in circumstances such as just after
powering on, after a momentary power interruption,
at the moment of recovery after a sudden drop of
voltage, etc. The microprocessor’s program some-
times does not run correctly in these cases due to a
malfunction of the internal logic circuit in the
processor. Manual resets help to assure normal
operation of the microprocessor’s program.
Figure 6 - Reset circuit
DC. A delay of several seconds is anticipated in the
DC voltage concentration signal because a C-R
combination is used in the circuit. A 100Ω resistor is
connected in series to protect the external circuit from
excessive current.
5-5 Circuit for damper control signal
Figure 8 shows an example circuit in which an H/L
signal which is output from port R60 (Pin No. 16)
and converted to an On/Off signal for controlling
the opening/closing of a damper. A 100Ω resistor is
connected in series to protect the external circuit from
excessive current.
5-4 CO2 concentration signal circuit
Port 91 (Pin No. 25) outputs a PWM signal which
represents a CO2 concentration in the range between
400 and 3000ppm. Figure 7 illustrates a sample circuit
for converting a PWM signal to a linear output of 0~3V
1M
FIC98648
2
3
10k
Analog output (0~3V)
for CO concentration
1
25
R91
2
100
6.2V
1M
22k
LM 324N
10µ
Figure 7 - CO2 concentration signal circuit
10k
FIC98648
2SA1015Y
10k
16
R60
100
1k
Damper control signal
6. 2V
Figure 8 - Damper control circuit
Revised 08/03
9
TECHNICAL INFORMATION FOR FIC98648
5-6 Circuit for manual benchmark reset
A circuit designed to allow for manual benchmark
reset is shown in Figure 9.
+4.4V
FIC98648
10k
27
KEO
Figure 9 - Manual benchmark reset circuit
5-7 Circuit for clock signal generator
FIC98648
When a ceramic oscillator is connected with the
clock in and out ports, Xin and Xout (Pins No. 2
and 1 respectively), a clock signal is activated in
FIC98648 by a built-in clock signal generator. A
sample circuit for connecting such an oscillator is
shown in Figure 10. Murata Electronics model
CST4.19MGW is a well-matched ceramic oscillator
for FIC98648. Before using a different oscillator,
please consult with Figaro or the oscillator
manufacturer.
XIN
XOUT
2
1
CST4. 19MGW
Figure 10 - Clock signal generator circuit
+3. 8V
5-8 Circuit for damper control signal threshold
A recommended circuit design for setting the damper
control signal threshold can be seen in Figure 11.
1k
JP
JP
JP
JP
4. 3k
10k
FIC98648
5-9 Sample circuit of damper control with TGS4160 and
FIC98648
A sample application circuit for damper control when
using a TGS4160 CO2 sensor and a FIC98648
microprocessor is shown in Figure 12. Please refer to
Technical Information for AM-4 for details.
24k
100k
10k
9
AIN2
103
Figure 11 - Damper control signal threshold circuit
Revised 08/03
10
TECHNICAL INFORMATION FOR FIC98648
~
Figure 12 - Application circuit
Revised 08/03
11
TECHNICAL INFORMATION FOR FIC98648
6. Hardware Specifications
*8-bit successive approximate type A/D converter
with sample and hold
- 8 analog inputs
6-1 Features
*4-bit single chip microcomputer
*Instruction execution time: 1.0µs (at 8MHz)
*Low voltage operation: 2.2V (at 4.2MHz)
*Basic instructions: 92
- ROM table look-up instructions
- 5-bit to 8-bit data conversion instruction
*Subroutine nesting: 15 levels maximum
*6 interrupt sources (External: 2, Internal: 4)
- Conversion time: 24µs (at 8MHz)
*Serial Interface with 8-bit buffer
- Simultaneous transmission and reception
capability
- 8/4-bit transfer, external/internal clock, and
leading/trailing edge shift mode
*Zero-cross detector (and external interrupt handler)
*Pulse output
- All sources each have independent latches, and
multiple interrupt control is available
*I/O port (23 pins)
- Buzzer drive/Remocon carrier
*High current outputs
- LED direct drive capacity: typ. 20mA x 8 bits
(Ports R5, R6)
*Two 12-bit Timer/Counters
- Timer, event counter, and pulse width measure- *Reset function
ment mode
- Watchdog timer reset
*Interval Timer
*Hold function
*Emulation pod: BM47C443
- Battery/Capacitor back-up
6-2 DC characteristics (see Table 8)
Parameter Symbol
Pins
Conditions
Min.
Typ.
Max.
Unit
Hysteresis
voltage
VHS
Hysteresis input
-
-
0.7
-
V
I
I
IN1
IN2
RESET, HOLD
Open drain ports
Input
current
V
DD = 5.5V, VIN = 5.5V/0V
-
-
±2
µA
kΩ
Input
resistance
R
IN
RESET
-
100
220
450
Output
leakage
current
Open drain
output ports
I
LO
V
DD = 5.5 V, VOUT = 5.5 V
-
-
2
µA
V
V
DD = 4.5V, IOL = 1.6mA
-
-
-
-
0.4
0.1
Output low
voltage
Ports
R4, R7, R8, R9
V
OL
V
DD = 2.2V, IOL = 20µA
Output low
current
IOL
Ports R5, R6
VDD = 4.5V, VOL = 1.0V
7
20
-
mA
Supply
current
(NORMAL
operating
mode)
V
DD = 5.5V, fc = 4MHz
DD = 3.0V, fc = 4MHz
DD = 3.0V, fc = 400kHz
-
-
-
2
1
4
2
1
I
DD
-
V
mA
V
0.5
Supply
current
(HOLD
operating
mode)
I
DDH
-
VDD = 5.5V
-
0.5
10
µA
Table 8 - DC characteristics
(Vss = 0, Topr = -30~+70˚C)
Revised 08/03
12
TECHNICAL INFORMATION FOR FIC98648
6-3 A/D conversion characteristics (Table 9)
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Unit
Analog reference voltage
VAREF
(Mask option)
VDD - 1.5
-
VDD
V
Analog reference
voltage range
∆VAREF
VAREF - Vss
2.7
-
-
V
Analog input voltage
Analog supply current
Nonlinearity error
Zero point error
Full scale error
VAIN
IREF
-
-
Vss
-
0.5
-
VDD
1.0
±1
V
-
-
-
-
-
mA
VDD = 2.7 ~5.5V
VAREF = VDD ± 0.001V
Vss = 0.000V
-
±1
-
LSB
-
±1
Total error
-
±2
Table 9 - A/D conversion characteristics
(Topr = -30~+70˚C)
6-4 AC characteristics (Table 10)
Parameter
Symbol
Condition
Min.
1.0
1.9
3.2
60
Typ.
Max.
Unit
V
DD = 2.7~5.5V
DD = 2.2~5.5V
Instruction Cycle Time
-
20
µs
t
cy
V
in RC oscillation
V
V
V
V
DD≥2.7V
High level clock pulse width
Low level clock pulse width
t
WCH
For external
clock
(XIN input)
DD<2.7V
DD≥2.7V
DD<2.7V
120
60
-
-
ns
t
WCL
120
-
A/D Conversion Time
A/D Sampling Time
Shift data Hold Time
-
-
-
-
-
-
t
ADC
24t
cy
µs
-
t
AIN
2t
cy
-
ns
t
SDH
0.5tcy-300
Table 9 - A/D conversion characteristics
(Vss = 0, Topr = -30~+70˚C)
Revised 08/03
13
TECHNICAL INFORMATION FOR FIC98648
6-5 Dimensions
Dimensions of FIC98648 are shown in Figure 13.
28
15
1
14
26.1 Max.
25.6 ± 0.2
1.243 Typ
1.0±0.1
0.46±0.1
M
0.18
1.778
Figure 13 - Dimensions of FIC98648
convey any license under its patent rights, nor the
rights of others.
Figaro Engineering Inc. (Figaro) reserves the right to
make changes without notice to any products herein
to improve reliability, functioning or design.
Information contained in this document is believed
to be reliable. However, Figaro does not assume any
liability arising out of the application or use of any
product or circuit described herein; neither does it
Figaro's products are not authorized for use as critical
components in life support applications wherein a
failure or malfunction of the products may result in
injury or threat to life.
FIGARO GROUP
HEAD OFFICE
OVERSEAS
Figaro Engineering Inc.
1-5-11 Senba-nishi
Mino, Osaka 562 JAPAN
Tel.: (81) 72-728-2561
Fax: (81) 72-728-0467
email: figaro@figaro.co.jp
Figaro USA Inc.
3703 West Lake Ave. Suite 203
Glenview, IL 60025 USA
Tel.: (1) 847-832-1701
Fax.: (1) 847-832-1705
email: figarousa@figarosensor.com
Revised 08/03
14
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