Identification of pin-open faults by measuring current or voltage change resulting from temperature change
AssigneeHewlett-Packard Company
InventorsJohn M. Heumann, Ronald J. Peiffer
Life of this patent
Estimating the term…
Abstract
A method and apparatus for determining whether semiconductor components are electrically connected to a printed circuit board. A voltage (or current) is connected to two traces leading to connections to a semiconductor component to be tested. The initial current (or voltage) is measured at an initial temperature. Then, the temperature of the semiconductor is changed. Current (or voltage) is measured again after the temperature change. A change in current (or voltage) indicates that the semiconductor component is electrically connected to the trace.
Claims28
An apparatus for determining the quality of the mounting of a semiconductor device in a circuit board by verifying electrical continuity between first and second conductive paths and the semiconductor device, at least one additional conductive device connected between the first and second conductive paths, the semiconductor device having first and second contacts, the first contact associated with the first conductive path and the second contact associated with the second conductive path, the apparatus comprising:
- a voltage source, electrically connected to the first and second conductive paths;
- a current monitor, connected to monitor the current through the conducting paths and the at least one additional conductive device;
- and
- means for changing the temperature of the semiconductor devices,
- wherein a change in current through the first and second conducting paths monitored before and after the temperature change indicates electrical continuity through the semiconductor device.
An apparatus for determining the quality of the mounting of a semiconductor device in a circuit board by verifying electrical continuity between first and second conductive paths and the semiconductor device, at least one additional conductive device connected between the first and second conductive paths, the semiconductor device having first and second contacts, the first contact associated with the first conductive path and the second contact associated with the second conductive path, the apparatus comprising:
- a current source, electrically connected to the first and second conductive paths, the current flowing through the at least one additional conductive device;
- a voltage monitor, connected to monitor voltage between the first and second conductive paths;
- and
- means for changing the temperature of the semiconductor device,
- wherein a change in voltage between the first and second conductive paths monitored before and after the temperature change indicates electrical continuity through the semiconductor device.
A method for determining the quality of the mounting of a semiconductor device in a circuit board by verifying electrical continuity between first and second conductive paths and the semiconductor device, at least one additional conductive device connected between the first and second conductive paths, the semiconductor device having first and second contacts, the first contact associated with the first conductive path and the second contact associated with the second conductive path, the method comprising the steps of:
- connecting a voltage source between the first and second conductive paths;
- monitoring the current through the first and second conductive paths and the at least one additional conductive device;
- and
- changing the temperature of the semiconductor device,
- wherein a change in current through the first and second conductive paths monitored before and after the temperature change indicates electrical continuity through the semiconductor device.
A method for determining the quality of the mounting of a semiconductor device in a circuit board by verifying electrical continuity between first and second conductive paths and the semiconductor device, at least one additional conductive device connected between the first and second conductive paths, the semiconductor device having first and second contacts, the first contact associated with the first conductive path and the second contact associated with the second conductive path, the method comprising the steps of:
- connecting a current source between the first and second conductive paths, the current flowing through the at least one additional conductive device;
- monitoring the voltage between the first and second conductive paths;
- and
- changing the temperature of the semiconductor device,
- wherein a change in voltage between the first and second conductive paths monitored before and after the temperature change indicates electrical continuity through the semiconductor device.
An apparatus for determining the quality of the mounting of a semiconductor device in a circuit board by detecting an open circuit between first and second conductive paths and the semiconductor device intended to be connected between the first and second conductive paths, at least one additional conductive device connected between the first and second conductive paths, the apparatus comprising:
- a voltage source, electrically connected to the first and second conductive paths;
- a current monitor, connected to monitor the current through the first and second conducting paths;
- and
- means for changing the temperature of the semiconductor device,
- wherein an absence of change in current through the first and second conductive paths monitored before and after the temperature change indicates an open circuit between the first and second conductive paths and the semiconductor device.
An apparatus for determining the quality of the mounting of a semiconductor device in a circuit board by detecting an open circuit between first and second conductive paths and the semiconductor device intended to be connected between the first and second conductive paths, at least one additional conductive device connected between the first and second conductive paths, the apparatus comprising:
- a current source, electrically connected to the first and second conductive paths;
- a voltage monitor, connected to monitor the voltage between the first and second conducting paths;
- and
- means for changing the temperature of the semiconductor device,
- wherein an absence of change in voltage between the first and second conductive paths monitored before and after the temperature change indicates an open circuit between the first and second conductive paths and the semiconductor device.
A method for determining the quality of the mounting of a semiconductor device in a circuit board by detecting an open circuit between first and second conductive paths and the semiconductor device intended to be connected between the first and second conductive paths, at least one additional conductive device connected between the first and second conductive paths, the method comprising the following steps:
- connecting a voltage source between the first and second conductive paths;
- monitoring the current through the conductive paths;
- and changing the temperature of the semiconductor device,
- wherein an absence of change in current through the first and second conductive paths monitored before and after the temperature change indicates an open circuit between the first and second conductive paths and the semiconductor device.
A method for determining the quality of the mounting of a semiconductor device in a circuit board by detecting an open circuit between first and second conductive paths and the semiconductor device intended to be connected between the first and second conductive paths, at least one additional conductive device connected between the first and second conductive paths, the method comprising the following steps:
- connecting a current source between the first and second conductive paths;
- monitoring the voltage between the first and second conductive paths;
- and
- changing the temperature of the semiconductor device,
- wherein an absence of change in voltage between the first and second conductive paths monitored before and after the temperature change indicates an open circuit between the first and second conductive paths and the semiconductor device.
Dependencies are inferred from the claim text.