Common mode feedback bias for low voltage opamps
AssigneeTexas Instruments Incorporated
InventorsJohn W. Fattaruso, Daramana G. Gata
Life of this patent
Estimating the term…
Abstract
The opamp with common mode feedback bias includes: a first differential pair M1 and M2 having first and second inputs; active load devices M3 and M4 coupled to the first differential pair M1 and M2; a common mode feedback circuit 20 coupled to the active load devices M3 and M4 for controlling the active load devices M3 and M4; a second differential pair M18 and M19 having a first input coupled to the first input of the first differential pair M1 and M2 and a second input coupled to the second input of the first differential pair M1 and M2; and current drivers M22 and M23 having control nodes coupled to the second differential pair M18 and M19 and outputs coupled to the active load devices M3 and M4.
Claims19
A circuit comprising:
- a first differential pair having first and second inputs;
- active load devices coupled to the first differential pair;
- a common mode feedback circuit coupled to the active load devices for controlling the active load devices;
- a second differential pair having a first input coupled to the first input of the first differential pair and a second input coupled to the second input of the first differential pair;
- and
- current drivers having control nodes coupled to the second differential pair and outputs coupled to the active load devices.
A circuit comprising:
- a first differential pair having first and second inputs;
- active load devices coupled to the first differential pair;
- a common mode feedback circuit coupled to the active load devices for controlling the active load devices;
- a second differential pair having a first input coupled to the first input of the first differential pair and a second input coupled to the second input of the first differential pair;
- current drivers having control nodes coupled to the second differential pair and outputs coupled to the active load devices;
- and
- a class A output stage coupled to the first differential pair and coupled to an input of the common mode feedback circuit.
Dependencies are inferred from the claim text.