Provided are a thin circuit device with show-through of thin metal wires prevented and a method of manufacturing the circuit device. The computing device can establish a secure connection to the portable device and determine an application on the portable device. The electrostatic gun can have a high-voltage generator that generates a negative polarity voltage between about 0 KV and about 100 KV during application of the powder coating composition, and the electrostatic gun can have a round spray nozzle. The data carrying service remains connected via a connection during all of the testing operations provided by one or more of the test circuits which enables the device to automatically determine the identity of the data carrying service. or lower, and an organic solvent; drying the applied conductive paste; putting a tab electrode on the dried conductive paste; and soldering the tab electrode.