voltage regualtor

I Just purchased this http://www.pololu.com/catalog/product/2111 It says it can out put 7 amps at 5 volts. I have it running off of a 12 volt lead-acid battery rated at 12 amps an hour. I connected this to a load of 250 mA and the output voltage is 4.5 volts some of my devices are not working correctly, What can I do about this?

Just a thought, did you try jumping the VIN (+12 volts) into the ENABLE pin and measure the output, bypassing the pullup resistor and see if it makes a difference? If not, you may have a defective board (polulu is good about exchanges).

arduinopi: I Just purchased this http://www.pololu.com/catalog/product/2111 It says it can out put 7 amps at 5 volts. I have it running off of a 12 volt lead-acid battery rated at 12 amps an hour. I connected this to a load of 250 mA and the output voltage is 4.5 volts some of my devices are not working correctly, What can I do about this?

Battery capacity is usually measured in Amp-hours (Amps times hours) not Amps per hour. Is your battery actually producing 12V? What is the input Voltage at the regulator?