US 12,244,277 B2
Common mode transient suppression
Bruno Luis Uberti, Ciudad Autonoma de Buenos Aires (AR); Juan Guido Salaya Velazquez, Ciudad Autonoma de Buenos Aires (AR); and Alejandro Gabriel Milesi, Buenos Aires (AR)
Assigned to Allegro MicroSystems, LLC, Manchester, NH (US)
Filed by Allegro MicroSystems, LLC, Manchester, NH (US)
Filed on Mar. 4, 2022, as Appl. No. 17/653,487.
Prior Publication US 2023/0283250 A1, Sep. 7, 2023
Int. Cl. H03F 3/45 (2006.01); H03F 3/21 (2006.01)
CPC H03F 3/45071 (2013.01) [H03F 3/211 (2013.01); H03F 2200/432 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A signal isolator, comprising:
a first die comprising a transmit module, wherein the first die has a first voltage domain; and
a second die comprising a receive module including a receive amplifier configured to receive from the transmit module a transmit signal that includes a differential signal and a common mode current, wherein the second die has a second voltage domain, wherein the first and second die are separated by an isolation barrier, and wherein the receive amplifier comprises:
a differential amplifier to receive the differential input signal from the transmit module; and
a common mode module configured to sense the common mode current and sink or source the common mode current and minimize changes to an input impedance of the receive amplifier, wherein the common mode module comprises a class AB amplifier.