A voltage down converter with submicroampere standby current for low-power static RAMs

A submicroampere standby current voltage downconverter (VDC) for high-density, low-power static RAMs is described. The current consumption of the VDC in standby mode can be decreased by using a novel low-current and temperature-independent current source circuit. The total current is less than 0.5 mu A at external voltage ranging from 3 to 5 V and at temperatures ranging from -20 to 80 degrees C. The voltage-follower circuits for standby and operation modes are stable despite the low current consumption in the standby mode. The phase margin of the voltage follower for standby mode is 50 degrees , and that for operation mode is 90 degrees . This indicates that the VDC is a promising circuit for battery-backup and high-density static RAMs.<>