A Low-Power Supply-Independent Analog Clock Frequency Divider for About 100 Division Factor

This paper presents an Analog Clock Frequency Divider (CFD) implemented in 0.35 μm technology, designed for ultra low-power operation in automotive applications during idlemode. The proposed CFD is designed with a double capacitive system and a comparator to achieve a division factor of about 100. The methodology has been validated through simulations and experimental measurements. The fabricated device achieves a measured division factor of 88. The device operates with an average power consumption of 96 nW at a 3V supply, with 62 nW consumed by the comparator and 34 nW by the capacitive system. The total area occupied by the frequency divider is 7000 μm2, with 4800 μm2 dedicated to capacitors. Experimental results show a total variation of 2% over a temperature range from - 40°C to 100°C.