US 12,113,524 B2
Active bootstrapping drivers
Edward Lee, Fullerton, CA (US); Michael Chapman, Long Beach, CA (US); Ravi Ananth, Laguna Niguel, CA (US); and Michael A de Rooij, Playa Vista, CA (US)
Assigned to Efficient Power Conversion Corporation, El Segundo, CA (US)
Filed by Efficient Power Conversion Corporation, El Segundo, CA (US)
Filed on Dec. 7, 2022, as Appl. No. 18/062,660.
Claims priority of provisional application 63/287,155, filed on Dec. 8, 2021.
Prior Publication US 2023/0179203 A1, Jun. 8, 2023
Int. Cl. H03K 17/687 (2006.01)
CPC H03K 17/6871 (2013.01) [H03K 2217/0063 (2013.01); H03K 2217/0072 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A bootstrapping gate driver for a high side FET having a drain terminal connected to a supply voltage, a source terminal connected to an output, and a gate terminal, the bootstrapping gate driver comprising:
an input for receiving a control signal; and
a bootstrap capacitor electrically connected between the supply voltage and ground when the control signal corresponds to a charging phase, thereby charging the capacitor, the capacitor being electrically connected to the gate terminal of the high side FET when the control signal corresponds to a driving stage;
an active charging circuit comprising: (i) a first charging FET, a diode or a diode-connected FET, and a second bootstrap capacitor for charging the first bootstrap capacitor up to the supply voltage without a diode voltage drop when the control signal corresponds to the driving stage; and (ii) a second charging FET to mitigate slow charging of the first bootstrap capacitor.