Revised 10/12
2
TECHNICAL INFORMATION FOR CDM4160
1. Basic Information
1-1 Features
* High selectivity to CO
2
* Long life
* Maintenance free
* Pre-calibrated
* Low cost
* Wide detection range
* Excellent durability
1-2 Applications
* Indoor air quality control in offices, homes,
and factories
* CO
2
monitors
* Agricultural applications
1-3 Specifications
The specifications of CDM4160 are contained
in Table 1. Depending on the customer's
target concentration range, Figaro offers three
versions of this module as indicated in Table 1.
Customized modules are available according to
special requests from customers. Please consult
with Figaro.
1-4 Dimensions (see Fig. 1 below)
Fig. 1 - CDM4160 dimensions
Table 2 - CDM4160 pin designations of CN1
NOTE:
CN1 should be MB5P-90S, mfg. by JST.
Recommended receptacle for connector: 05JQ-BT, mfg. by JST.
u/m: mm
2. Structure and Functions
2-1 Solid electrolyte CO
2
sensor TGS4160
The sensor changes its output voltage in response to
exposure to CO
2
gas. The sensor should not be directly
connected with low-input impedance equipment. To
read sensor output, amplified voltage (CP4) should be
used. Please refer to “TGS4160 Technical Information”
for details as to the characteristics of the sensor.
2-2 Sensor's output signal voltage (CP4)
The sensor’s output can be read as an amplified
voltage
(as taken from the differential amplifier).
Voltage should be read from this pin.
2-3 Microprocessor
The microcomputer takes data and renews it once per
second. The processor calculates CO
2
concentrations
based on the difference between current sensor
output and a baseline value (which represents the
sensor output value in fresh air).
2-4 Thermistor signal output voltage (CP3)
The thermistor’s output signal voltage, which is
used for compensation of the sensor’s temperature
dependency, can be read at this pin.
2-5 Concentration setting for control signal (JP1, JP2)
Concentrations utilized for control signals (i.e. the
control concentration
) can be changed by modifying
the settings of JP1 and JP2 as shown in Table 3. The
module is pre-set at Mode I before shipment.
2-6 Baseline reset switch (SW1)
The baseline value may be manually reset using this
switch. When this switch is pushed, the sensor’s
output at that moment is memorized as 400ppm of
CO
2
(the baseline value in fresh air). When the switch
SW1
LED1
LED2
LED3
JP2
JP1
JP3
CN1
12345
45
Gas sensor
TGS4160
3
ø3
26 Max
t=1.6(mm)
4.5 Max
3
19
2.5
0.64
7
Microprocessor
60
CP3
CP4
Pin No.
Name
Description
1
V
IN
Power supply unit
2
V
CONC
CO
2
concentration output
3
CTRL
Control signal output
4
TRBL
Trouble signal output
5
GND
Common ground
