A neuron circuit can switch between two functions: as an input neuron circuit, and as a hidden neuron circuit. An error circuit can switch between two functions: as a hidden error circuit, and as an output neuron circuit. A switching circuit is configured to be capable of changing the connections between the neuron circuit, a synapse circuit, and the error circuit. The synapse circuit includes an analog memory that stores data that corresponds to the connection strength between the input neuron circuit and the hidden neuron circuit or between the hidden neuron circuit and the output neuron circuit, a writing circuit that changes the data in the analog memory, and a weighting circuit that weights an input signal in reaction to the data of the analog memory and outputs the weighted output signal. The analog memory includes a transistor comprising an oxide semiconductor with extremely low off-state current.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A module comprising: a first circuit; a second circuit; and a third circuit; wherein the first circuit comprises a first function of amplifying a first signal and outputting the amplified first signal to the second circuit, and a second function of converting the first signal from current to voltage, amplifying the converted first signal and outputting the amplified first signal to another module; wherein the second circuit comprises a first multiplier circuit configured to change data corresponding to a connection strength between the first circuits, an analog memory configured to store the changed data, and a second multiplier circuit configured to output a second signal corresponding to the amplified first signal that has been weighted in accordance with the changed data; wherein the third circuit is configured to convert the second signal from current to voltage and output the converted second signal to an outside; and wherein the analog memory comprises a transistor comprising an oxide semiconductor in a channel formation region. 2. The module according to claim 1, wherein the first circuit is a neuron circuit. 3. The module according to claim 1, wherein the second circuit is a synapse circuit. 4. The module according to claim 1, wherein the third circuit is an error circuit. 5. An electronic device comprising the module according to claim 1, further comprising: an encoder configured to encode video data; wherein the video data comprises first video data and second video data; and wherein the module compares the first video data and the second video data when the first video data and the second video data are input to the module, and obtains a motion vector from the first video data to the second video data when the first video data and the second video data match. 6. A module comprising: a neuron circuit; a synapse circuit; and an error circuit; wherein the synapse circuit comprises a first multiplier circuit configured to change data corresponding to a connection strength between the neuron circuits, an analog memory configured to store the changed data, and a second multiplier circuit configured to output a second signal corresponding to the amplified first signal that has been weighted in accordance with the changed data, and wherein the analog memory comprises a transistor comprising an oxide semiconductor in a channel formation region. 7. The module according to claim 6, wherein the neuron circuit comprises a first selector circuit configured to select whether the neuron circuit functions as an input neuron circuit or as a hidden neuron circuit, and wherein the neuron circuit is configured to amplify an input signal and output the amplified input signal to the synapse circuit when the neuron circuit functions as the input neuron circuit, and wherein the neuron circuit is configured to convert the input signal from current to voltage and amplify the converted input signal and output the amplified input signal to another synapse circuit when the neuron circuit functions as the hidden neuron circuit. 8. The module according to claim 6, wherein the error circuit comprises a second selector circuit configured to select whether the error circuit functions as an output neuron circuit or as a hidden error circuit, wherein the error circuit is configured to convert the current output from the synapse circuit to voltage and output the converted voltage to another module when the error circuit functions as the output neuron circuit, and wherein the error circuit is configured to multiply a derivative of the converted voltage and a difference signal between an instructor signal and a reference signal when the error circuit functions as the hidden error circuit.