Hi can I know why my grove sound sensor didnt give 1023 value once I play around with the potentiometer. but when i try with other type of sound sensor it works.
The microphone amplifier on the Grove Sound Shield is a LM358. If you consult the LM358 data sheet you will see that the output voltage does not go to the supply voltage, it is not a "rail to rail op amp". See page 4, the Output Voltage−High Limit section of the specifications. With a 5V supply the high output voltage limit is (typically) 3.5V (716 ADC counts).
another one is arduino sound module with lm393 as its amplifier.
The LM393 is not, strictly speaking, an amplifier, it is an op amp voltage comparator. Its output is a digital (0 or 1 [0 or 1023]) signal.
So what is the difference between these lm393 and lm 2904(i saw from grove sound sensor)? Can both work on my project (sound decibel meter)? is it lm393 for digital signal while 2904 for analog signal?
A LM393 is a dual voltage comparator. Its output is digital so if input to an Uno AD converter will read 0 or 1023, nothing in between. The LM2904 (LM358) is an amplifier. If input to an Uno AD converter it will read from near 0 to around 716 with analog values between.
I would assume that a decibel meter would need an analog sensor so the one with the LM2904 (LM358) could work, but the digital (on-off) LM393 will not.
Yes.
1 Like
alright , now much clear. I did referred to one author on the decibel meter project (IoT Based Decibelmeter with Sound Sensor & ESP8266 ). However, I think this approach is good and simple way to get the final reading by just mapping the analog signal. I really appreciate if other idea or tutorial can be share with me.
Is this a tutorial?
Answer no.
So do not post in the tutorials section.
Post moved here.
Hello ground. Is this section you mean it? what about if I try with esp32 , the max values of analog can obtain is about 2867 right?
Is there any analog sound sensor that have 'rail to rail' amplifier like I can have a full range of analog and no limitation?
What about sparkfun sound sensor with LMV324, can it give 5v for output voltage if 5v was supplied?
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.