Apparatus and method for automated testing of a progammable analog gain stage
AssigneeAdvanced Micro Devices, Inc.
InventorJeffrey Max Blumenthal
Life of this patent
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Abstract
A Built-In Self-Test (BIST) circuit and test method are employed for automated testing of a programmable analog gain stage. The BIST circuit and operating method advantageously use the natural redundancy of a multiple-channel circuit for detecting circuit faults. More specifically, the BIST circuit utilizes the natural redundancy of the identical signal paths for multiple-channel, such as stereo, audio operation. A left channel and a right channel ideally function identically so that a fault in one channel of the left channel and the right channel signal paths is detected by mutually comparing the operation of the two channels.
Claims27
A Built-In Self-Test circuit for testing an analog gain stage in a multiple-channel system, the Built-In Self-Test circuit comprising:
- a plurality of output voltage amplifiers;
- a plurality of programmable attenuator networks, ones of the plurality of programmable attenuator networks having an output terminal coupled to an input terminal of ones of the output voltage amplifiers;
- and
- a comparator having a plurality of input terminals, ones of the plurality of input terminals being coupled to output terminals of ones of the plurality of output voltage amplifiers so that the comparator mutually compares the operation of the plurality of output voltage amplifiers.
A Built-In Self-Test circuit for testing an analog gain stage in a multiple-channel system, the Built-In Self-Test circuit comprising:
- a first channel including:
- a first output voltage amplifier having an input terminal and an output terminal;
- and
- a first programmable attenuator network having an input terminal for receiving an input voltage, an input terminal for receiving a gain control signal, and an output terminal coupled to the input terminal of the first output voltage amplifier;
- a second channel including:
- a second output voltage amplifier having an input terminal and an output terminal;
- and
- a second programmable attenuator network having an input terminal for receiving an input voltage, an input terminal for receiving a gain control signal, and an output terminal coupled to the input terminal of the second output voltage amplifier;
- and
- a comparator having an input terminal coupled to the output terminal of the first output voltage amplifier and an input terminal coupled to the output terminal of the second output voltage amplifier so that the comparator mutually compares the operation of the first channel and the second channel.
A Built-In Self-Test circuit for testing an analog gain stage in a multiple-channel system, the Built-In Self-Test circuit comprising:
- a first channel programmable attenuator network having a first input terminal for receiving a reference voltage, a second input terminal for receiving an input signal voltage, a control terminal for receiving a gain signal, and an output terminal coupled to an input terminal of a first channel output voltage amplifier;
- a first channel comparator having a first input terminal coupled to receive a signal selected from an output voltage of the first channel output voltage amplifier and the input signal voltage, a second input terminal coupled to receive a signal selected from an output voltage of a second channel output voltage amplifier and the reference voltage;
- a second channel programmable attenuator network having a first input terminal for receiving a reference voltage, a second input terminal for receiving an input signal voltage, a control terminal for receiving a gain signal, and an output terminal coupled to an input terminal of the second channel output voltage amplifier;
- and
- a second channel comparator having a first input terminal coupled to receive a signal selected from an output voltage of the second channel output voltage amplifier and the input signal voltage, a second input terminal coupled to receive a signal selected from an output voltage of the first channel output voltage amplifier and the reference voltage.
A method of operating a Built-In Self-Test circuit for testing an analog gain stage in a multiple-channel system, the method comprising:
- for a first analog gain stage channel and a second analog gain stage channel:
- applying an input signal voltage across a programmable attenuator network;
- selecting an attenuation value for attenuating the input signal voltage;
- controlling the programmable attenuator network to attenuate the input signal voltage by the selected attenuation value;
- and
- applying the attenuated input signal voltage to the analog gain stage under test to generate an output voltage;
- and
- comparing the output voltage of the first analog gain stage channel to the output voltage of the second analog gain stage channel.
A method of providing a Built-In Self-Test circuit for testing an analog gain stage in a multiple-channel system, the method comprising:
- providing a first channel programmable attenuator network having a first input terminal for receiving a reference voltage, a second input terminal for receiving an input signal voltage, a control terminal for receiving a gain signal, and an output terminal coupled to an input terminal of a first channel analog gain stage;
- providing a first channel comparator having a first input terminal coupled to receive a signal selected from an output voltage of the first channel analog gain stage and the input signal voltage, a second input terminal coupled to receive a signal selected from an output voltage of a second channel analog gain stage and the reference voltage;
- providing a second channel programmable attenuator network having a first input terminal for receiving a reference voltage, a second input terminal for receiving an input signal voltage, a control terminal for receiving a gain signal, and an output terminal coupled to an input terminal of the second channel analog gain stage;
- and
- providing a second channel comparator having a first input terminal coupled to receive a signal selected from an output voltage of the second channel analog gain stage and the input signal voltage, a second input terminal coupled to receive a signal selected from an output voltage of the first channel analog gain stage and the reference voltage.
Dependencies are inferred from the claim text.