US 2006/0085702 A1 · Integrated circuit fuses having corresponding storage circuitry

Abstract

Storage circuitry (66) may be used to store the values of fuses (77) so that storage circuitry (66) can be read instead of fuses (77). By accessing the fuse values from storage circuitry (66) rather than from fuses (77), there will be no sense current to fuses (77) that may cause marginal fuse blowage for fuses that have not yet been blown. This helps to prevent the situation in which an unblown fuse is erroneously read as having been blown. The use of storage circuitry (66) thus significantly improves the reliability of fuse module (20). For some embodiments, selection storage circuitry (64) may be used to determine whether storage circuitry (66) may be read or whether one of fuses (77) must be read in order to retrieve the desired current fuse value. The fuse value stored in storage circuitry (66) can also be used as direct hardware signals (80).

Claims35

Dependent claims

A method for accessing a fuse having corresponding storage circuitry and corresponding selection storage circuitry, comprising:

requesting a read to the fuse;
and
based on the corresponding selection storage circuitry, selectively sensing the fuse to provide a read value in response to the read request;
if the corresponding selection storage circuitry has a first value, reading the corresponding storage circuitry to provide the read value in response to the read request;
and
if the corresponding selection storage circuitry has a second value, sensing the fuse to obtain a sensed fuse value, storing the sensed fuse value into the corresponding storage circuitry, and using the sensed fuse value to provide the read value in response to the read request.

3 more elements

An apparatus, comprising:

at least one on-demand-stored fuse;
at least one automatically-stored fuse;
storage circuitry having a first storage location corresponding to the at least one on-demand-stored fuse and a second storage location corresponding to the at least one automatically-stored fuse;
control circuitry, coupled to the at least one on-demand-stored fuse, the at least one automatically-stored fuse, and the storage circuitry, which stores a sensed value of the at least one automatically-stored fuse into the first storage location in response to at least one of a reset or a power-up event and which stores a sensed value of the at least one on-demand-stored fuse into the second storage location only in response to a read request to the at least one on-demand-stored fuse;
selection storage circuitry corresponding to each of the first storage location and second storage location of the storage circuitry;
and
selection circuitry, coupled to the storage circuitry and selection storage circuitry, which determines, based on the selection storage circuitry, whether, in response to a read access to one of the at least one on-demand-stored fuse or the at least one automatically-stored fuse, the storage circuitry is accessed or the one of the at least one on-demand-stored fuse or the at least one automatically-stored fuse is sensed to provide a read value in response to the read access.

4 more elements

An apparatus, comprising:

at least one on-demand-stored fuse;
at least one automatically-stored fuse;
storage circuitry having a first storage location corresponding to the at least one on-demand-stored fuse and a second storage location corresponding to the at least one automatically-stored fuse;
control circuitry, coupled to the at least one on-demand-stored fuse, the at least one automatically-stored fuse, and the storage circuitry, which stores a sensed value of the at least one automatically-stored fuse into the first storage location in response to at least one of a reset or a power-up event and which stores a sensed value of the at least one on-demand-stored fuse into the second storage location prior to a read request to the at least one on-demand-stored fuse;
selection storage circuitry corresponding to each of the first storage location and second storage location of the storage circuitry;
and
selection circuitry, coupled to the storage circuitry and selection storage circuitry, which determines, based on the selection storage circuitry, whether, in response to a read access to one of the at least one on-demand-stored fuse or the at least one automatically-stored fuse, the storage circuitry is accessed or the one of the at least one on-demand-stored fuse or the at least one automatically-stored fuse is sensed to provide a read value in response to the read access.

4 more elements

Dependencies are inferred from the claim text.

Integrated circuit fuses having corresponding storage circuitry

Life of this patent

Integrated circuit fuses having corresponding storage circuitry

Life of this patent

Abstract

Claims35