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I have tested ADC.when I apply voltages more than 9.6 v it read 1024. so I think voltage reference of it's ADC is 9.6v .Any body did the same?

mohsenabutalebi wrote:I have tested ADC.when I apply voltages more than 9.6 v it read 1024. so I think voltage reference of it's ADC is 9.6v .Any body did the same?

Woohoo. Thats more than Espressif wrote in their datasheets.
Have a look here: http://bbs.espressif.com/viewtopic.php? ... 1545#p1545

All digital IO pins are protected from over-voltage with a snap-back circuit connected between the
pad and ground. The snap back voltage is typically about 6V, and the holding voltage is 5.8V. This
provides protection from over-voltages and ESD. The output devices are also protected from
reversed voltages with diodes.

found in "0B-ESP8266__Hardware_User_Guide__EN_v1.1.pdf"

Also there a topic about 3.9. ADC (Analog-to-digital Converter)

ESP8266EX is embedded with a 10-bit precision SARADC. Currently, TOUT (Pin6) is defined as ADC
interface..

The input voltage range is 0 to 1.0 V when TOUT is connected to external circuit.

mohsenabutalebi wrote:I have tested ADC.when I apply voltages more than 9.6 v it read 1024. so I think voltage reference of it's ADC is 9.6v .Any body did the same?

I assume you mean 0.96V, not 9.6V. It can very well the case. It's probably a multiple of some diode's bandgap voltage. It's very hard to make it exactly 1.0V.

I'm pretty sure you don't want to apply 9v to any pin unless you want to fry it.

Did you slowly ramp up the voltage using a high accuracy power source to come to that number? Can you please explain how you arrived at 9.6v.