Temperature compensated RC oscillator for signal conditioning ASIC using source bulk voltage of MOSFET

An oscillator circuit comprising:

• a first current source;
• and
• a comparing circuit coupled to the first current source;
• the comparing circuit comprising an NMOS device and second current source coupled to the NMOS device;
• and resistance coupled between the source and the bulk of the NMOS device, the bulk of the NMOS device is coupled to ground, wherein the second current source injects compensation current into the resistance, wherein the second current source is generated based on a reference bias current, which is constant over temperature to the first order and a reference voltage is generated that is also constant over temperature to the first order.

An oscillator circuit comprising:

• a first current source;
• and
• a comparing circuit coupled to the first current source;
• the comparing circuit comprising an NMOS device and second current source coupled to the NMOS device;
• and resistance coupled between the source and the bulk of the NMOS device, the bulk of the NMOS device is coupled to ground, wherein the second current source injects compensation current into the resistance, which includes a PMOS device coupled to the NMOS device;
• and an inverter, wherein the PMOS device, NMOS device and the inverter form a closed loop, wherein the PMOS device allows the oscillator circuit to operate at a higher frequency with lower power consumption and the PMOS device causes the NMOS device to behave more like a switch.