US 12,170,518 B2
Ethernet fail-safe relay
Eskil Carl Fredrik Göth, Lund (SE); and Bror Mats Karlsson, Malmö (SE)
Assigned to SCHNEIDER ELECTRIC BUILDINGS AMERICAS, INC., Carrollton, TX (US)
Filed by SCHNEIDER ELECTRIC BUILDINGS AMERICAS, INC., Carrollton, TX (US)
Filed on Apr. 15, 2022, as Appl. No. 17/659,345.
Claims priority of provisional application 63/266,288, filed on Dec. 31, 2021.
Prior Publication US 2023/0216491 A1, Jul. 6, 2023
Int. Cl. H03K 17/687 (2006.01); H04L 49/40 (2022.01)
CPC H03K 17/6871 (2013.01) [H04L 49/40 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A passive Ethernet by-pass switch comprising:
a first connection configured to be coupled to a first Ethernet port;
a second connection configured to be coupled to a second Ethernet port; and
switching circuitry including at least one internal switch operable to allow network communication between the first connection, the second connection, and at least one Ethernet controller,
the at least one internal switch including a depletion mode transistor operable to bridge the first connection to the second connection to establish communication between the first connection and the second connection;
a watchdog circuit configured to receive a heartbeat signal from the at least one Ethernet controller or a microcontroller coupled to the at least one Ethernet controller and to provide a signal indicative of a presence or an absence of the heartbeat signal; and
a power monitoring circuit coupled to the switching circuitry and the watchdog circuit, the power monitoring circuit configured to operate the Ethernet by-pass switch to cease providing power to the depletion mode transistor.