Providing designers with a surface-mount option for higher power circuit designs, resistor manufacturer Stackpole Electronics Inc. recently introduced a molded surface-mount metal oxide resistor technology that features resistance values from 3 KΩ to 1 MΩ, in power ratings up to 3 W. Designated the SMX Series, these resistors are expected to find acceptance in a range of automotive, computer, power supply, telecommunication, industrial and instrumentation applications. These rugged power resistors are direct replacements for axial-leaded resistors. The SMX Series is available with resistance values from 3 KΩ to 1 MΩ in tolerances of ±5%, with a temperature coefficient of resistance (TCR) of ±200 ppm/°C. The operating temperature is specified from -50°C to 150°C, and the maximum pulse voltage is 800 V.
The SMX Series also employs a unique J-lead termination, which provides excellent thermal coefficient of expansion (TCE) ratio matching. This can reduce thermal stresses that often cause surface-mount components to crack or the solder joints to fail. This also will aid transitions from through-hole to surface-mount components in circuit board designs.
With samples available, typical pricing for an SMX resistor is $0.25 each in production quantities. Allow lead times of six weeks.