The smart card and the IRD voltage respectively have 3V 5 v±10%, namely 2.7 V to 5.5 v.gsm smart card also 5V, but the handset internal other parts are 3V, therefore and the smart card has an extra voltage conversion component.
Card internal operation in addition to hardware and its software, usually requires a kernel cos (Chip operatingsystem) to provide services, that is, the smart card operating system, often called the chip operating system Cos,cos generally have their own security system, Its safety performance is usually the important technical index to measure the Cos. Cos function includes: transmission management, file management, security system, command interpretation.
The smart card internal software system architecture is as follows: hardware (hardware) →cos→ap (Application)
Some COS can provide services in the Java language, producing a branch called Java Card. Visa International has therefore used the Java language to develop the visa Openplatform card, later renamed Global Platform. The MasterCard International organization supports another Multos (Multti keyboard-based System) platform. Whether global platform or Multos, application service providers can develop new application units (applets) on both platforms to run specific functions without having to go through the mask development process, significantly reducing the cost and time of development.