Power Up / Power Down Circuit
Using an MOS voltage
reference
Using a bandgap
voltage reference
The cells pictured above are temperature insensitive Power Up/Power Down circuits.
Design Specifications:
- The inputs to the cell are only VDD and VSS
- The output is less than 0.7V if 0.7V < VDD < 4.1V +/- 0.25V and is more than VDD-0.2V if VDD > 4.1V +/- 0.25V
- A small hysteresis (100-200mV) is included in the cell
The cells were designed using a 0.6 micron, double metal, single poly process.