Helo,
My name is Thomas. I’m writing because I have seen on product list a gas sensor MQ7. I would like to make a CO detector using MQ7. Could You tell me if my connections are good? And is it dummy if I use pins number 2,4,6 for VCC or pins 1,3,5? (connect them conversely - at my wire).
But I have another one: I have read in datasheet that the MQ7 need two kind of heather voltage (V and 1,4V), so can I just connect heather pin (pin 4 in my wire) to VDC = 5V? Or I should connect it somewhere where I could change the voltage (for exaple using PWM from microprocessor) ?
I don’t know where you see 1.4V. You should be able to connect Vc and Vh if you keep the voltage below 5V. I have connected them and seen it responding to gases. It certainly doesn’t break it.