46-nA High-PSR CMOS Buffered Voltage Reference With 1.2–5 V and −40 ◦C to 125 ◦C Operating Range

A nanopower, buffered CMOS voltage reference designed to operate across the entire industrial temperature range (from $- 40~^{\circ }$ C to $125~^{\circ }$ C) and with an input voltage range from 1.2 to 5 V (automotive applications) is presented. The solution provides 390 mV at $20~^{\circ }$ C and is implemented in a standard BCD technology featuring 160-nm CMOS devices. It is characterized by an average temperature coefficient of 200 ppm/°C, a line sensitivity (LS) of 0.138%/V, and a power supply rejection of −83 dB at 100 Hz. In addition, the circuit occupies a die area of 0.146 mm2 (with the reference circuit alone covering 0.043 mm2) and maintains a highly stable current consumption of around 45 nA across various process and input voltage conditions (25 nA for the reference circuit alone) while providing a maximum output current of $630~\mu $ A with a load regulation of 0.016 mV/ $\mu $ A.