Drinking driver detection circuit
Car drivers, motorcyclists despite prohibit drinking and driving, but also have occurred, in this case the circuit can be detected the odor of alcohol when. Issued a do not dri
Click here to download the full size of the above Circuit.
nk and drive the voice prompts sound immediately. When not detected the odor of alcohol, I wish you a safe journey home, the voice is raised. To warn drivers not to drink and drive, with a reminder. (1) to Tuen Mun Road and the principle of the circuit components shown in FIG 6H44. QM-NJ9 circuit is alcohol sensor. QM-NJ9 exposed to alcohol after the ignorant, the resistance value of A, B between the reduction potential of the point B rises, the more concentrated alcohol, the higher the B point potential. This signal voltage by a sensitivity adjustment potentiometer RP, sliding arm removed and added to the LM358 dual voltage comparator, feet, and the comparator, pin voltage reference by the crown, R sub- pressure decision that, feet the potential of the product is fixed at V-Vcc/(R3 + R4) a 1.47V. The two LM358 comparator input is connected to the anti- pick. According to the voltage comparator principle known: If, pin signal voltage is less than 1. 47V voltage, feet set, the comparator O pin output low, LED2 off, off. While the lower comparator output high Royal basis. LED3 (green) positive bias, light, and touch the hair of voice circuits TP-1106K Wei Ying foot end, the speaker issued a Y I wish you a safe journey home, said the driver to be wine. If, pin signal voltage is higher than 1. 47V, the next comparator pin output low, LED3 off, off. The comparator O pin output high, LEDZ (red) light, and trigger TI - 1106K feet TGl the end, the speaker BL issued a do not drink and drive, the warning that the drivers alcohol consumption exceeds the standard, should be mandatory stop driving. Island is QM-I.U9 filament FF current limiting resistor, both ends of the filament heating voltage stability (5 persons o- z) v, it will ensure that alcohol sensor with high sensitivity and stability work. Because alcohol sensors before work need to preheat 5-lOmin. Wait until the stability can be detected, and any time there is a two comparator output high, in order to prevent false triggering language tone circuit, so set up a manual switch S2. Just then detected at S2, immediately you can let go. VD1, VD2 buck diode tube. TP-1106K in order to ensure the right fit supply voltage (2.5 ~ 4.5V). Timing components hurricane, C adjustable voice circuits operating frequency, thus changing the sound tone.
characters left: