Semtech SX863 Capacitive Touch Controller
Semtech SX863 Capacitive Touch Controller is a fully-integrated 8-channel solution for capacitive touch buttons and sliders in proximity detection applications with up to 10cm of proximity detection. THE SX863 features dedicated capacitive sense inputs in addition to eight general-purpose I/O ports (GPIO). Each GPIO is typically configured as an LED driver with an independent PWM source for enhanced lighting control such as intensity and fading. The SX8638 includes a capacitive 10-bit ADC analog interface with automatic compensation of up to 100pF. The high-resolution capacitive sensing supports a wide variety of touchpad sizes/shapes. It allows capacitive buttons to be created using thick overlay materials (up to 5mm) for a highly robust and ESD immune system design.
Integrated firmware and multi-time programmable memory provide flexibility to modify key firmware parameters (gain, threshold, scan period, auto offset compensation) in the field without the need for firmware development. The Semtech SX863 Capacitive Touch Controller supports the 400kHz I2C serial bus data protocol and includes a field-programmable slave address. The tiny 4mm x 4mm footprint makes it an ideal solution for portable, battery-powered applications where power and density are at a premium.
Features
- Complete eight-sensor capacitive touch controller for buttons and sliders
- Pre-configured for two buttons and a slider
- 8x LED drivers with individual intensity, fading control, and Autolight Mode
- 256 steps PWM linear and logarithmic control
- Proximity sensing up to several centimeters
- High-resolution capacitive sensing
- Up to 100pF of offset capacitance compensation at full sensitivity
- Capable of sensing through overlay materials up to 5mm thick
- Optimized for portable applications, extremely low power
- 8µA typical in Sleep Mode
- 80µA typical in Doze Mode (195ms scanning period)
- 175µA typical in Active Mode (30ms scanning period)
- 15ms to 1500ms programmable scanning periods
- Auto offset compensation
- Eliminates false triggers due to environmental factors (temperature, humidity)
- Initiated on power-up and configurable intervals
- Multi-time in-field programmable firmware parameters for flexibility with on-chip user-programmable memory for fast, self-contained start-up
- "Smart" wake-up sequence for easy activation from doze
- No external components per sensor input
- Internal clock requires no external components
- Differential sensor sampling for reduced EMI
- 400KHz fast-mode I2C interface with interrupt
- -40°C to +85°C operating temperature range
- Lead-free, MLPQ-UT28 package
Applications
- Notebooks, netbooks, and portable/handheld computers
- Cell phones and PDAs
- Consumer products
- Instrumentation
- Automotive
- Mechanical button replacement
Videos
Application Circuit
Publicado: 2016-07-20
| Actualizado: 2022-03-11