Enhanced-sensitivity controller simplifies touch-sensing design

Freescale’s MPR031 and MPR032 capacitive touch-sensor controllers simplify the design of a touch-sensitive interface.

With increased sensitivity and a specialised feature set, these controllers can be applied in a range of touch-sensing applications, including touch pads and switch replacements. Separate touch and release trip thresholds further simplify design by providing hysteresis and electrode independence.

The MPR03x devices control up to 3 touch pads with communications provided via I²C and an optional IRQ output to advise of electrode status changes. These controllers are optimised to manage two electrodes with interrupt functionality, or three electrodes with the interrupt disabled.

Proximity capacitive touch sensors offer significant advantages over mechanical buttons and switches: They are more convenient to use, have no moving parts to wear out, and can be easily integrated into intelligent systems.

 

FEATURES 1.71V to 2.75V operation 8µA supply current with two electrodes being monitored, a 64ms response time and IRQ enabled 3µA maximum shutdown current Continuous independent auto-calibration for each electrode input 2mm x 2mm x 0.65mm 8-lead DFN package Operating temperature range: -40°C to 85°C

APPLICATIONS Switch replacements Touch pads Remote controls Mobile devices Lighting controls

 

 

 

The KITMPR031EVM board is available to members of Future Electronics’ Board Club at: www.my-boardclub.com/manf-offers.htm Non-members can apply for membership at: www.my-boardclub.com/apply_2.htm Development boards and evaluation kits are free and available only to qualified Board Club members.

 

Freescale / MPR03x