Based on type, the market has been divided into thick-film resistor
, thin-film resistor, current-sensing resistor, and others.
Available SMD solutions include thick-film resistors
in [D.sup.2]PAK casings (Figure 4) or a combination of series / parallel circuits with SMD carbon film MELF resistors.
RPC Series anti-surge, thick-film resistors
are surface mount replacements for wirewound and axial-leaded film products.
Since I wanted to create a striking example, I had accumulated the costs of embedding high Dk planar capacitance materials and ceramic thick-film resistors
. This created a very expensive board, which is what I intended to underscore my point.
The reason is that their geometric variations cannot be smoothed by laser trimming (they are buried) to the tight tolerances of 0.5 to 1 percent required of analog circuitry -- the great advantage of surface thick-film resistors
. Nonetheless, careful process control (primarily thickness) has enabled these materials to be used successfully in 5 to 10 percent tolerance applications.