US 12,261,429 B2 · Short detection circuit

Abstract

A short detection circuit includes a first transistor, a switched load circuit, a second transistor, a switched capacitor circuit, and a comparator. The first transistor is configured to conduct a load current. The switched load circuit is coupled to the first transistor. The switched load circuit is configured to switchably draw a test current. The second transistor is coupled to the first transistor. The second transistor is configured to conduct a sense current. The sense current includes first and second portions that are respectively representative of the load current and the test current. The switched capacitor circuit is coupled to the second transistor. The switched capacitor circuit is configured to generate a short detection voltage representative of the second portion. The comparator has a first comparator input coupled to the switched capacitor circuit. The comparator is configured to compare the short detection voltage to a short threshold voltage.

Claims21

Dependent claims

A short detection circuit, comprising:

a first transistor having a first current terminal, second current terminal, and a first control terminal;
a first resistor coupled between the second current terminal and a ground terminal;
a second transistor having a third current terminal, a fourth current terminal, and a second control terminal, in which:
the third current terminal is coupled to the first current terminal;
and
the second control terminal is coupled to the first control terminal;
a current source having a current output and a current input, in which the current input is coupled to the fourth current terminal;
a second resistor coupled between the current output and the ground terminal;
a switched capacitor circuit coupled between the current output and the ground terminal;
and
a comparator having a comparator output, a first comparator input, and a second comparator input, in which:
the first comparator input is coupled to the switched capacitor circuit;
and
the second comparator input is coupled to a reference voltage terminal.

11 more elements

A short detection circuit, comprising:

a first transistor configured to conduct a load current;
a switched load circuit coupled to the first transistor, the switched load circuit configured to switchably draw a test current;
a second transistor coupled to the first transistor, the second transistor configured to conduct a sense current, in which the sense current includes first and second portions, the first portion is representative of the load current, and the second portion is representative of the test current;
a switched capacitor circuit coupled to the second transistor, the switched capacitor circuit configured to generate a short detection voltage representative of the second portion;
and
a comparator having an output, a first comparator input, and a second comparator input, in which the first comparator input is coupled to the switched capacitor circuit, and the comparator is configured to compare the short detection voltage to a short threshold voltage.

3 more elements

A system, comprising:

a power terminal;
a load terminal;
and
an electronic fuse (EFUSE) circuit including:
a first transistor configured to conduct a load current from the power terminal to the load terminal;
a switched load circuit coupled to the first transistor, the switched load circuit configured to switchably draw a test current;
a second transistor coupled to the first transistor, the second transistor configured to conduct a sense current, in which the sense current includes first and second portions, the first portion is representative of the load current, and the second portion is representative of the test current;
a switched capacitor circuit coupled to the second transistor, the switched capacitor circuit configured to generate a short detection voltage representative of the second portion;
and
a comparator having an output, a first comparator input, and a second comparator input, in which the first comparator input is coupled to the switched capacitor circuit, and the comparator is configured to compare the short detection voltage to a short threshold voltage.

7 more elements

Dependencies are inferred from the claim text.

Short detection circuit

Life of this patent

Short detection circuit

Life of this patent

Abstract

Claims21