Voltage regulator circuit
View Patent ↗A voltage regulator circuit has a standby amplifier with an output coupled to a gate of an output transistor. An active amplifier has an output coupled to the gate of the output transistor and to a gate of a replica follower transistor. A voltage regulated output is coupled to a source of the output transistor.
1. A voltage regulator circuit, comprising:
a standby amplifier having an output coupled to a gate of an output transistor;
an active amplifier having an output coupled to the gate of the output transistor and to a gate of a replica follower transistor; and
a voltage regulated output coupled to a source of the output transistor.
2. The circuit of claim 1 , further including a chip enable signal coupled to the gate of the output amplifier.
3. The circuit of claim 2 , further including a capacitor between the chip enable signal and the gate of the output transistor.
4. The circuit of claim 1 , wherein the replica follower transistor is significantly smaller than the output transistor.
5. The circuit of claim 1 , wherein the active amplifier is an open loop control amplifier.
6. The circuit of claim 5 , wherein a positive input of the active amplifier is coupled to a reference voltage and a negative input is coupled to a replica follower circuit.
7. The circuit of claim 6 , wherein a positive input of the standby amplifier is coupled to the reference voltage and a negative input coupled to a output circuit.
8. A voltage regulator circuit, comprising:
a closed loop amplifier having an output coupled to a gate of an output transistor;
an open control amplifier having an output coupled to the gate of the output transistor and a gate of a replica follower transistor; and
a voltage regulated output coupled to a source of the output transistor.
9. The circuit of claim 8 , wherein an external voltage is coupled to a drain of the output transistor and a pair of resistors is coupled in series between the source of the output transistor and a ground.
10. The circuit of claim 9 , further including a chip enable signal coupled to the gate of the output transistor.
11. The circuit of claim 10 , further including a capacitor coupled between the chip enable signal and the gate of the output transistor.
12. The circuit of claim 8 , wherein an external voltage is coupled to a drain of the replica follower transistor and a pair of resistors is coupled in series between the source of the replica follower transistor and a ground.
13. The circuit of claim 12 , wherein a negative input of the open control amplifier is coupled to a node between the pair of resistors.
14. The circuit of claim 13 , wherein a positive input of the open control amplifier is coupled to a reference voltage.
15. A voltage regulator circuit comprising:
an amplifier having an output coupled to a gate of an output transistor;
a chip enable signal directly electrically connected to a capacitor, the capacitor directly electrically connected to the gate of the output transistor; and
a voltage regulated output coupled to a source of the output transistor.
16. The circuit of claim 15 , wherein the amplifier includes a standby amplifier and an active amplifier, wherein an output of the active amplifier is coupled to the gate of a replica follower transistor and the gate of the output transistor.
17. The circuit of claim 16 , wherein the output transistor is larger than the replica follower transistor.
18. The circuit of claim 15 , further including a reference voltage coupled to an input of the amplifier.
19. The circuit of claim 18 , wherein a second input of the amplifier is coupled to a node between a pair of resistors coupled between a source of the output transistor and a ground.