PRODUCT INFORMATION

EM1820 - Evaluation Module for TGS1820
Description:
This module facilitates evaluation of the characteristics ofthe acetone gas sensor TGS1820.*1The sensor sensitivity (⊿VOUT) is obtained by calculating
the difference between the voltage output in a clean
atmosphere and the voltage output in gas. *2*1 Please refer to Product Information for TGS1820 forsensor characteristics.
*2 This module will output the response of the TGS1820
sensor as a voltage change. Temperature compensation
for sensor output is not a feature provided by this module.

Dimensions:

Circuit Diagram:

IC3

VR14VH
monitor

CP5RL

5IC1

VOUT2(hold)

CP4Sensor
TGS1820

VR2JP5JP4JP33

VOUT1GNDJP1

Pin Connections:
JP2GS1CP2CP11CN1

5CP5CP4Gas sensor socket
1 2 3 4 5
2.50.64(TGS1820)

0.64

3.3 1.6

u/m:mm3.0max

11.6

D/A
converter

VSS
IC2

D1

LED(Green)

Microcomputer

CP368.0

LED(Orange)

2.3V(Lo:2.0V)

-RS

2

VDD

CP3SW1VIN

CP2+EM1820

DC/DC
converter

JP6CN1
1Switch39.0

D3CP1(+5V)* The sensor is to be put in the sensor socket as shownin the above photo.
* Suggested female connectors mating to the 5 pinconnector (JST MB5P-90S):
JST XHP-5P or JST 05JQ-BTPin No.

Name

Description

1VIN

2

VOUT1

Output voltage(VRL)(continuous)

3

VOUT2

Output voltage(VRL)
Hold value*4

VH monitor

Sensor applied voltage(VH)
Monitor

5

GND

GroundInput voltage

4.9~5.1V DC* Hold Value: Under Hi/Lo drive mode, sensor output voltage istaken at 20 seconds after pressing the switch, just before sensor
applied voltage switches from Lo to Hi, and kept as a ‘hold value’.
This value is updated every time the switch is pressed.

The sensor’s sensitivity (⊿VOUT) is calculated fromthe output in a clean atmosphere (VOUT [Air]) and theoutput in gas (VOUT [Gas]) using the following formula:⊿VOUT =VOUT[Gas] – VOUT[Air]PRODUCT INFORMATION

Driving Conditions:
Setting by driving conditions (Jumper pin connections)
Drive mode

JP1

JP2

JP3

JP4

JP5

〇 : Connected－ : No connection
Continuousdrive mode

JP6Continuousdrive mode

Remarks
Initial factory setting

2.3VOptional driving condition for evaluation purpose.
VH warranty for TGS1820 sensor is
Please note that the productextended to sensor performances in continuous drive mode only.

Hi/Lo drive
mode

Note: Please do not change jumper pin positions except for JP4 and JP5.

Continuous
Continuous
drive drive
modemode (Default factory setting)

Hi/Lodrive
Hi/Lodrive
modemode (Optional setting)
Switch ON

2.3V

2.3V

VH

VH

20sec.

Exposureto gas

2.0V

LED(Orange) Illumination

Hi/Lo drive mode
Switch ON

20sec.

Sensor Operation Mode

10sec

5sec

BlinkingONSampling pointSensor Operation Mode

* The green LED lights when the correct input voltage VIN is2.3Vapplied.

* The green LED lights when the correct input voltage VIN isapplied.

to gas* Constant heater voltage (VH) at 2.3V
is applied to the sensor.

* The Hi voltage at 2.3V is applied to the sensor until a buttonon this module is pushed to switch to the Lo voltage only oncefor 20 seconds. After switching to the Lo voltage, an orange
LED will blink 3 times within the first 10 seconds just before
the time to gas exposure, when the orange LED is on.

ExposureVH

2.0V

Initial Factory Settings and Sensor Applied Voltage
10sec

5sec

Sampling point* A load resistor (RL) is set at 10 Ω with factory
setting of ajumper pin to JP1.
BlinkingONLED(Orange) Illumination* Factory setting of the sensor applied voltage is 2.3V. It canbe changed by adjusting a variable resistor VR1.

* Expose the sensor to test gas during 5 seconds when theorange LED is on. Then measure the sensor output voltage
at the moment just before switching back to the Hi voltage.
The Hi/Lo drive mode is an optional sensor driving condition
offered for evaluation purpose.
This sensor drive mode may bring higher selectivity to acetone
than using continuous drive mode, depending on design andapplication of a complete instrument incorporating this sensor.

Specifications:
Item

Specification

Model No.

EM1820

Product Name

Evaluation module forTGS1820

Applicable sensor

TGS1820

Operating conditions

0~50˚C (no condensation)

Output voltage (VOUT)

0~2.5V

Initial Factory Settings and Sensor Applied Voltage* A load resistor (RL) is set at 10 Ω with factory setting of ajumper pin to JP1.
* For Hi/Lo drive mode, factory settings of the Hi voltage is 2.3V,
and 2.0V for the Lo voltage.
They can be changed by adjusting variable resistors;
VR1 for Hi voltage, and VR2 for Lo voltage.

NOTE:
Please do not adjust VR1 or VR2 unless necessary.

FIGARO ENGINEERING INC.
1-5-11 Senba-nishi
Mino, Osaka 562-8505 JAPAN
Phone: (81)-727-28-2045
URL：www.figaro.co.jp/en/

REV: 07/23