Ultra-miniature volume controls, trimmers, and switches
Resistance Technology is the worlds largest manufacturer of custom hearing aid volume
controls, trimmers, and switches. RTI has produced over 50 million various types of
hearing aid components over the last 19 years. As an innovator, RTI is proactive and
partners with our customers to improve the next-generation hearing instruments by using
cutting-edge technologies and automation.
Meeting Market demands for smaller components
With the advent of CIC (Completely-In-the-Canal) hearing devices, hearing instrument
manufacturers have pushed the physical size requirement to new dimensions, driving
component sizes to the ultra-miniature stage. A typical CIC hearing aid has an elliptical
shaped faceplate that is approximately .250" to .500" and has an overall length
of approximately .500" to .750". RTI has a full line of components to make your
hearing aid assembly process easier and more reliable.
Custom engineering
Our in-house design, automation, and robotic manufacturing means rapid prototyping and
precision manufacturing at lower costs to our customers. RTI's vertical integration
includes injection insert molding, metal stamping, and robotics workcells valued at over
one million dollars per cell for precision assembling and testing. Our
proprietary-designed volume control and trimmer-resistive elements are fabricated and
laser trimmed in our microelectronics hybrid facility. Our Class 10,000 clean room
environment ensures our goal of zero defects.
Custom engineering parameters
RTI components are designed to be accurate and durable, meaning that the operation life
can be greater than 15,000 rotational cycles at maximum electrical rating and temperature
ranging from -25 degrees C to +55 degrees C. RTI's unique double-ball wiper design and
metallurgy improves performance for the new hearing instruments. Some of the volume
control models have exchangeable knobs to help match the needs of the customer who may
have numerous hearing aid styles. The following are some typical engineering
specifications used in designing our volume controls and trimmers: Operational torque,
Stop guide torque, Rotational angle, Potentiometer terminals, Wiper, Knob, Base, Resistor
substrate, Resistor element, Potentiometer, Overall resistance, Wattage rating, and
Contact resistance.
