A mixed-mode ASIC for interface control of smart-card parcmeter

CIPAF is a microcontroller´s peripheral ASIC working on a two wires serial bus. It implements functions of the smart-card parcmeter PIAF, the first on-board car parcmeter. PIAF has a pocket calculator size, is battery powered and parking fees are charged on a smart card. CIPAF mainly controls LCD display, power supply batteries, ambient temperature measurement for accurate real-time clock generation and includes the low-power part of voltage elevators required for reading and writing into smart cards. It also generates a 1 MHz clock for the microcontroller. Size and cost reduction dictate the fewest external components possible which in turn impose to CIPAF using a new solution for ESD protection on its pins in contact with the smart card. The solution has been patented. A mixed-mode analog-digital implementation was the only way for meeting both low power consumption and high accuracy requirements.<>