Dallas Semiconductor Introduces Battery-Backup Controller for Data Protection in Point-of-Sale Terminals
Dallas Semiconductor Corp. introduced the DS3600, a comprehensive secure battery-backup controller for data protection in point-of-sale terminals. First in a family of secure battery-management products, the DS3600 provides active tamper detection and rapid-erasure key memory. It supports FIPS-140 security levels 3 and 4, and meets the highest requirements of Common Criteria. The DS3600 is packaged in a CSBGA, a preferred choice for certification because no pins are exposed to the outside world so the package is resistant to tampering.
The memory architecture(1) on the DS3600 is innovative and unique to secure battery-backup controllers from Dallas Semiconductor. The DS3600's proprietary, on-chip nonvolatile SRAM is used for storage of encryption keys. This memory architecture constantly complements the SRAM cells to eliminate the possibility of memory imprinting due to oxide stresses. As a result, this technology prevents the passive detection of data remnants in stressed memory cells. When the DS3600 generates a tamper alarm, the entire 64-byte array is cleared within 100ns. This erasure of data is this fast because the memory's high-speed direct hardwired clearing function and on-chip power source ensure active erasure.
The DS3600 has tamper-detection inputs to interface with system voltages, resistive meshes, external sensors, and digital interlocks. Using a low-power operation, it also monitors those components continuously. The device monitors the integrated real-time-clock (RTC) crystal oscillator and will invoke a tamper response if the oscillator frequency falls outside the set threshold. The internal digital temperature sensor has a programmable rate-of-change detector that protects the DS3600's encryption key memory from thermal attacks. Competitive secure battery-backup products do not offer such thermal backup protection. The DS3600 constantly monitors primary power. In the event of a power failure, an external battery power source is automatically activated to keep the SRAM, RTC, and tamper detection circuitry alive.
Prior to the DS3600, numerous discrete components were required to perform all these same functions. Using the DS3600 enables the designer to minimize board space used to implement a security solution.
