US 2026/0074609 A1 · NON-ISOLATED DC-DC CONVERTER WITH POWER-SWITCH SHORT CIRCUIT DETECTION

Abstract

A non-isolated DC-DC converter detects short circuits of its switching devices to avoid faulty and unsafe operating conditions. The converter includes a transformer and switching circuitry that includes upper switches and middle switches of a primary-side inverter and lower switches of a secondary-side rectifier. Short-circuit detection circuitry has (1) a resistive divider to establish normal values of a primary-side test node and a secondary-side test node in a non-short-circuit condition during pre-operation with all the switches in an OFF condition, and (2) sensing circuitry operative during the pre-operation of the converter to detect abnormal values of the primary-side and secondary-side test nodes indicative of an abnormal short circuit of the upper, middle or lower switches.

Claims11

Dependent claims

A non-isolated DC-DC converter, comprising:

a transformer having a primary winding and a secondary winding;
switching circuitry including upper switches and middle switches of a primary-side inverter and lower switches of a secondary-side rectifier, the primary-side inverter having a primary-side test node between the upper and middle switches and being directly connected to the secondary-side rectifier to provide the converter output current as the sum of primary current and secondary current during ON intervals of a switching cycle;
and
short-circuit detection circuitry including (1) a resistive divider to establish normal values of the primary-side test node and a secondary-side test node in a non-short-circuit condition during pre-operation of the converter with all the switches in an OFF condition, and (2) sensing circuitry operative during the pre-operation of the converter to detect abnormal values of the primary-side and secondary-side test nodes indicative of an abnormal short circuit of the upper, middle or lower switches.

1 more element

A method of testing a non-isolated DC-DC converter for the presence of a short circuit in any of upper, middle and lower switches thereof, comprising:

incorporating a resistive divider to establish normal values of a primary-side test node and a secondary-side test node in a non-short-circuit condition during pre-operation of the converter with all the switches in an OFF condition;
and
operating sensing circuitry during the pre-operation of the converter to detect abnormal values of the primary-side and secondary-side test nodes indicative of an abnormal short circuit of the upper, middle or lower switches.

Dependencies are inferred from the claim text.

Non-isolated dc-dc converter with power-switch short circuit detection

Life of this patent

Non-isolated dc-dc converter with power-switch short circuit detection

Life of this patent

Abstract

Claims11