27929 Parallax Inc, 27929 Datasheet - Page 2

• Manufacturer Part Number: 27929
• Description: Flow Sensors CO2 Gas Sensor Module
• Manufacturer: Parallax Inc

Specifications of 27929

• Supply Voltage: 6.5 V to 12 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Connecting and Testing
The 4-pin SIP header on the Gas Sensor Module makes it easy to connect to a breadboard or SIP socket.
The four connections are defined in the table below. Connection to a microcontroller, such as the BASIC
Stamp
detecting the alarm signal and another output for controlling the internal heater.
Pin Definitions and Ratings
Copyright © Parallax Inc.
®
* The CNTL line is internally pulled down to 0V via a 150 kΩ resistor.
NOTE: Sensor may rattle if shaken – this is normal.
TP1
TP2
TP3
TP4
module or Propeller chip, is pretty straight forward and requires two I/O pins; one input for
Pin
E1
E2
E3
E4
Test Point 1+
Test Point 3+
Test Point 2-
Test Point 4-
Name
CNTL
GND
ALM
VIN
Heat switch input from microcontroller, active HIGH
Alarm output to host microcontroller, active HIGH
Input voltage
Ground, connects to common ground
Buffered output of sensor (buffer/amplifier)
Ground, connects to common ground
Trip Level voltage set by potentiometer (R3)
Ground, connects to common ground
CO2 Gas Sensor Module (#27929)
Function
v1.0 2/25/2010 Page 2 of 4
+6.5 – 12VDC
0V – 12VDC
0V – 3.35V
0V – 3.3V
0V / 3.3V
Level
0V
0V
0V