1234 A B C D 4321 D C B A Title NumberRevisionSize A4 Date:1-May-2013 Sheet of File:D:?MQ?MQ?.ddbDrawn By: OUTA 1 INA- 2 INA+ 3 GND 4 INB+ 5 INB- 6 OUTB 7 VCC 8 U1 LM393 RE1 POT2 VCC 1 2 3 4 J1 CON4 VCC GND AOUT DOUT C1 0.1uF A 1 H 2 A 3 B 6 H 5 B 4 U2 MQ-X R1 5R1 VCC R2 1K VCC AOUT D1 LED DOUT VCC R3 4.7K AOUT DOUT