Abstract: In one embodiment, a waveform generating device includes a first DA converter converting input data, a controller outputting a first signal having a command value based on the input data, and a second signal having a command value differing by a constant value from the first signal, a second DA converter converting the first signal, a third DA converter converting the second signal, and a combiner combining the output of the first DA converter, the output of the second DA converter, and the output of the third DA converter. When a value of a predetermined first high-order bit of the input data is inverted, the controller changes the command value of the first signal such that a value of the first high-order bit or a second high-order bit different from the first high-order bit is inverted.

Abstract: In one embodiment, a waveform generating device includes a first DA converter converting input data, a controller outputting a first signal having a command value based on the input data, and a second signal having a command value differing by a constant value from the first signal, a second DA converter converting the first signal, a third DA converter converting the second signal, and a combiner combining the output of the first DA converter, the output of the second DA converter, and the output of the third DA converter. When a value of a predetermined first high-order bit of the input data is inverted, the controller changes the command value of the first signal such that a value of the first high-order bit or a second high-order bit different from the first high-order bit is inverted.

Abstract: The charged particle beam writing apparatus includes a position deflection control circuit. First digital data that is to be used for circuit diagnosis is transmitted from the position deflection control circuit to the DAC amplifier unit at the same rate as a rate of writing on a product reticle and stored in a first maintenance memory. Second digital data is output from a digital section included in the DAC amplifier unit in response to the first digital data and stored in a second maintenance memory. A maintenance clock generator generates a clock signal and reads the first digital data stored in the first maintenance memory and the second digital data stored in the second maintenance memory. The first digital data thus read is compared with the second digital data thus read for each bit to diagnose the digital section.

Abstract: The charged particle beam writing apparatus includes a position deflection control circuit. First digital data that is to be used for circuit diagnosis is transmitted from the position deflection control circuit to the DAC amplifier unit at the same rate as a rate of writing on a product reticle and stored in a first maintenance memory. Second digital data is output from a digital section included in the DAC amplifier unit in response to the first digital data and stored in a second maintenance memory. A maintenance clock generator generates a clock signal and reads the first digital data stored in the first maintenance memory and the second digital data stored in the second maintenance memory. The first digital data thus read is compared with the second digital data thus read for each bit to diagnose the digital section.