how power nokia 3310 without battery i.e directly with dc supply.

Impedance of supply? The phone starts to transmit aftert teh splash screen. If the voltage drops then, it'll cut out.

what should I do now I am using bench power supply which is using LM317 and can give 1A of power.

What voltage do you have it set to?

3.6V may be a little low - I'm unsure when it cuts out. I'd try 4V. If you have a scope, look at the voltage while starting. Does it drop?

hey dude its works as u said I have now connected a 3300uf and now mobile has become switch on and it works fine. an I have to increase voltage to 4V also.

do u know upto how much voltage we can give to the mobile what's its max rating.

Thanks for your help.

:)

The battery will run from 3.3 - 4.2V or so. I would be surprised if it stopped working before 5V or so, but to be safe, you should not exceed 4.2V.

I have a 'USB charger' for this, which consists only of a 1.8 ohm resistor wired to a plug. Works well.

This is one of two things:

1) Either the phone thinks the battery is dead as others have mentioned. You need to get your voltage in the correct range.

or

2) The phone is expecting a "smart battery" whereby it sends a digital signal to it and expects back some sort of message. In that case, your supply will never work because it won't ack the message. I've seen this happen on some phones. Don't know about this model.

James.

I'd keep the supply at 3.6V. If my memory is ok, the capacitor you fitted fixed it as the phone pulls intermittent 2A+ current bursts. If the batt voltage dips by >200mV during a burst the phone will shutdown.

Look at the supply with a cro (phone on etc). Look at the v-drop pulses, maybe add more smaller caps in //

nikhilele scrobe on the papyrus:

A quick look at the Nokia website might help you. It shows that the

3310 can be used with either the ACP-7 (3.7V) or the ACP-8 (5.3V) chargers. The Nokia in-car charger is 5.1V. Take your pick.

--
John B

now when we are using such a big value of capacitor then it can harm voltage regulator at start up due to surge current required by capacitor to charge it.

It should not harm a LM317 based supply, it should current limit properly.