Allegro makes the UDN2891A-T that will source 500mA. http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?freeText=udn2981&langId=-1&storeId=10001&productId=1762681&search_type=jamecoall&catalogId=10001&ddkey=http:ParametricXmlView
The suffix 'A' (all devices) indicates an 18-lead plastic dual in-linepackage with copper lead frame for optimum power dissipation. Undernormal operating conditions, these devices will sustain 120 mA continuouslyfor each of the eight outputs at an ambient temperature of +50°C and a supplyof 15 V.
im looking for a source driver than drive 500mA per output channel.