relay coil voltage problem

[SnakeBite]

Hi,

i designing an battery operated product that has voltage range of 11-14.4V and i'm using a 12v coil relay. in the datasheet says the min coil voltage is 9.6V and the maximum voltage is 13.2V. what is the simplest way to lower the voltage to the coil voltage range of the relay?

here's the relay's datasheet 
http://www.mouser.com/ds/2/307/ly_dsheet_gwj002-e2-10-48034.pdf

i thought about using two diode in series but it's tricky to get exactly 1.2-1.4v voltage drop with 75mA.

thanks
Ido

[retrolefty]

Well if you look up the coil current then you could calculate a series resistor that drops 1.2 vdc when the battery is at 14.4 vdc.

[Fank1]

Personally I would not worry about it, but just put a 16 ohm resistor in series with the coil.
At 75 ma this will give you a 1.2 volt drop.

[Andreas]

Hello,

You are simply using the wrong relay.
There exist other 12V relays with 9-16 or even 9-18V operating range.
BTW. the upper voltage is usually for the upper operating temperature point.
If you dont need the whole temperature range you can usually allow for higher coil voltages.

With best regards

Andreas

[SnakeBite]

thanks guys 

[fcb]

I wouldn't sweat it, it's probably just spec'd at 13.2V to allow for indefinate on time at peak operating temperature.  If you plan on running the coil for along time, look up 'coil economizer' circuits.