| MIPS | average 25 MIPS, peak 40 MIPS |
| CPU | 32-bit RISC, speed 33MHz |
| Voltage | 2.7 - 5.5V |
| Memory | 8KB to 128KB EEPROM |
| Power dissipation | < 10mW (compatible with contact/less operation) |
| Clock speed | on-chip clock generation up to 50MHz,
external 1-5MHz used for I/O transmit/receive clock |
| Performance | 15µs for DES encryption/decryption,
< 500ms for 1024-bit RSA encryption/decryption |
| Cryptography | embedded library of specialized mathematical functions for implementing
cryptographic algorithms,
fast multiply - shift for high speed software cryptography |
| Internal details | 32-bit data paths, sixteen 32-bit registers + special-purpose registers
with various lengths,
two execution modes: Native & Java, native instructions are 1 - 4 bytes, two privilege levels: User & System |
The ST22 differs from the standard Java Card model in very few ways; the primary one is the presence of an on-chip clock.
It also comes with a comprehensive development environment containing SmartJ code generation tools (C, C++ and Java compilers and an assembler/linker), a SmartJ instruction set simulator, a cycle assurance simulator and C, C++, Java and assembler source level debuggers. Users can modify or add new OS functions, modify or change key upper-layer components such as the Loader or Virtual machine, download applications after initial card issuance, rapidly port the complete software onto a new component, tailor the cryptographic library to meet the user's exact needs, and still have room for specific hardware and software blocks to be plugged in.