Negative Voltage Generator and Current DAC Based Regulator For Flash Memory

This paper presents a negative voltage generator and regulator having configurable output from OV to -10V. The output magnitude of regulator is precisely controlled by 6-bit current based Digital to Analog converter (DAC). The output of regulator is used to bias the control gate of flash memory cells during sector erase operation. The negative charge pump is operating on analog supply of 3.3V and employs 7 stages to generate negative output of -10V at 200μA current load condition. The voltage regulator is operating on positive supply of 1.2V and output of negative charge pump acts as negative supply. The negative voltage generator and regulator is designed and simulated in 90nm triple well CMOS Technology to support the maximum capacitive load of entire sector up-to 250pF to 1nF.