Embedded electronic fuses

A system, comprising:

• a read amplifier having a first input, a second input, a first output, and a second output, the read amplifier comprising:
• a first inverter having an input and an output, wherein the output of the first inverter is coupled to the first output of the read amplifier;
• and
• a second inverter having an input and an output, wherein the output of the second inverter is coupled to the second output of the read amplifier and the input of the first inverter, and the input of the second inverter is coupled to the output of the first inverter;
• one or more first fuses coupled to the first input of the read amplifier;
• one or more second fuses coupled to the second input of the read amplifier;
• a first switch;
• a second switch, wherein the first switch and the second switch are coupled in series between a bus and the read amplifier;
• and
• a voltage detection circuit having an input and an output, wherein the input of the voltage detection circuit is coupled between the first switch and the second switch, and the output of the voltage detection circuit is coupled to a control input of the first switch.

A method for reading a bit stored in electronic fuses, the electronic fuses comprising one or more first fuses and one or more second fuses, the method comprising:

• detecting a voltage between a first switch and a second switch is above a threshold, wherein the first switch and the second switch are coupled in series between a bus and a read amplifier;
• turning on the first switch is response to detecting the voltage between the first switch and the second switch is above the threshold;
• receiving a signal indicating a read operation of a read circuit for another bit is done;
• turning on the second switch in response to receiving the signal;
• sensing a resistance difference between the one or more first fuses and the one or more second fuses using the read amplifier, the read amplifier including a first inverter and a second inverter that are cross coupled;
• latching a logic value at an output of the first inverter to obtain a first latched logic value;
• latching a logic value at an output of the second inverter to obtain a second latched logic value, wherein the first latched logic value and the second latched logic value are complementary;
• and
• outputting at least one of the first latched logic value and the second latched logic value.

A method for reading a bit stored in electronic fuses, the electronic fuses comprising one or more first fuses and one or more second fuses, the method comprising:

• detecting a voltage on a supply rail is above a threshold;
• turning on a switch is response to detecting the voltage on the supply rail is above the threshold, wherein the switch is coupled between the supply rail and a read amplifier;
• sensing a resistance difference between the one or more first fuses and the one or more second fuses using the read amplifier, the read amplifier including a first inverter and a second inverter that are cross coupled;
• latching a logic value at an output of the first inverter to obtain a first latched logic value;
• latching a logic value at an output of the second inverter to obtain a second latched logic value, wherein the first latched logic value and the second latched logic value are complementary;
• and
• outputting at least one of the first latched logic value and the second latched logic value.