An electronic circuit may include an integrated current-source with an output terminal that may couple to the output of a power converter to draw current from the power converter. Therefore, uniformity of a deposited film is improved, compared with the conventional lateral flow ALD apparatus in which a supplied source gas and reaction gas constantly flow in only one direction on the substrate. The inner housing has a hollow cylindrical body extending longitudinally between a lower guide plate and an upper guide band. An optical control signal comprising data that are based on the nonlinear characteristic is transmitted to the optical transmitter.