US 12,136,878 B2
Regulator circuit and multi-stage amplifier circuit
Min-Hung Hu, New Taipei (TW)
Assigned to RICHTEK TECHNOLOGY CORPORATION, Zhubei (TW)
Filed by Richtek Technology Corporation, Zhubei (TW)
Filed on Sep. 21, 2022, as Appl. No. 17/933,877.
Claims priority of application No. 111100308 (TW), filed on Jan. 4, 2022.
Prior Publication US 2023/0216401 A1, Jul. 6, 2023
Int. Cl. H02M 3/155 (2006.01); H03F 3/16 (2006.01)
CPC H02M 3/155 (2013.01) [H03F 3/16 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A multi-stage amplifier circuit, comprising:
a front stage amplification circuit, which is configured to operably generate a front stage amplification signal according to a difference between a primary feedback signal and a primary reference signal;
at least one output adjustment circuit, which is configured to operably generate a driving signal according to the front stage amplification signal; and
at least one output transistor, which is under control by the driving signal to operably generate an output signal;
wherein the primary feedback signal is correlated with the output signal, and wherein a gate-source voltage of the at least one output transistor is determined by the driving signal, so as to determine an output current of the output signal;
wherein each of the at least one output adjustment circuit includes:
an adjustment transistor, which is biased by a differential current of the front stage amplification signal; and
an impedance adjustment circuit coupled to the adjustment transistor, wherein the impedance adjustment circuit includes:
an impedance adjustment device, which is biased by the differential current of the front stage amplification signal, wherein a resistance of the impedance adjustment device is determined by a difference between an adjustment feedback signal and an adjustment reference signal, wherein the adjustment feedback signal is correlated with the output signal;
wherein the driving signal is determined by a drain-source voltage of the adjustment transistor and a voltage across the impedance adjustment device, wherein the voltage across the impedance adjustment device is determined by a product of the resistance of the impedance adjustment device multiplied by the differential current of the front stage amplification signal.