Quick SMD resistor questions

[spooney]

Does 101 stand for 100 ohms? And what is the difference between thick and thin film smd resistors?I believe i'm lookin for something in the 1/8th watt range. They are gate resistors for the power supply fets in a memphis 16-PB1KD.

[Eva]

Yes, 101 stands for 100 ohms. The last digit is the number of zeroes to add to the right.

Thick-film and thin-film are two different resistor manufacturing processes. You can search google for further explanation.

[hermanv]

101 almost always means 100 Ohms.
102 = 1K
103 = 10K
etc.


Courtesy of Bourns Resistors:

Thin Film Vs. Thick Film
The basic distinction between thick film and thin film is the method of deposition of the metallization. In thick film, specially formulated pastes are applied and fired onto a substrate. The pastes are usually applied with a silk screen method and the substrate is of 96% alumina ceramic. In thin film, a layer of metallization is puttered onto a substrate and then a pattern is etched into the previously applied metal layer, the substrates are often 99.5% alumina ceramic, silicon, or glass.

Thick film is an additive process where layers of termination and resistor material are added to the substrate, while thin film is a subtractive process where the unwanted material is etched away in a succession of selective photoetching processes. The use of photolithographic processes to form thin film patterns produce much finer lines and traces than thick film processes.

Thin film is very appropriate for high density and high frequency applications. Thick and thin film technologies are well suited for low to medium volume custom circuits. Thick film has the advantages of lower cost (both of tooling up new designs and of production runs), of being able to handle more power, and of being able to service a higher range of ohmic values. Thin film has the advantages of tighter absolute and ratio tolerances and more environmentally stable components with lower noise and tighter TCR than thick film.

Thin film technology is used wherever precision resistors are needed. Differential Op-amp Input Differential Op Amps are needed in electrically dirty environments to reject noise transients that are picked up by wires. The differential Op Amps subtracts the noise out of the two signal wires. Thin film tracking capabilities are needed in these circuits to ensure that the input resistors do not affect the contents of the incoming signal.

ps. For Audiophiles bulk foil surface mount are the best if by no means the cheapest.

[Perry Babin]

You can use either type of resistor.

The wattage is generally determined by the size. Use dial calipers to measure the resistor. The most common sizes are 0805 (0.080" x 0.050") and 1206 (0.120" x 0.060").