C8051F700 Enables Robust, Cost-Effective Capacitive Touch Sensing

The C8051F7XX device families are fully integrated, mixed-signal, system-on-a-chip MCUs.

Features

• High-speed pipelined 8051-compatible microcontroller core (up to 25 MIPS)
  
• In-system, full-speed, non-intrusive debug interface (on-chip)
  
• 10-bit 500 ksps Single-ended ADC
  
• Precision calibrated 24.5 MHz internal oscillator 16 kB of on-chip Flash memory
  
• 512 bytes of on-chip RAM
  
• Implemented SMBus/I2C, UART, and SPI serial interfaces
  
• Four general-purpose 16-bit timers
  
• Capacitive Sense interface with 32 input channels
  
• Programmable Counter/Timer Array (PCA)
  
•  On-chip internal voltage reference
  
• On-chip Watchdog timer
  
• On-chip Power-On Reset and Supply Monitor
  
• On-chip Voltage Comparator
  
• 54 general purpose I/O

With on-chip power-on reset, VDD monitor, watchdog timer, and clock oscillator, the C8051F70x/71x devices are truly stand-alone, system-on-a-chip solutions. The Flash memory can be reprogrammed even in-circuit, providing non-volatile data storage, and also allowing field upgrades of the 8051 firmware. User software has complete control of all peripherals, and may individually shut down any or all peripherals for power savings.

The C8051F70x/71x processors include Silicon Labs’ 2-Wire C2 Debug and Programming interface, which allows non-intrusive (uses no on-chip resources), full speed, in-circuit debugging using the production MCU installed in the final application. This debug logic supports inspection of memory, viewing and modification of special function registers, setting breakpoints, single stepping, and run and halt commands. All analog and digital peripherals are fully functional while debugging using C2. The two C2 interface pins can be shared with user functions, allowing in-system debugging without occupying package pins.

Each device is specified for 1.8–3.6 V operation over the industrial temperature range (–45 to +85 °C). An internal LDO is used to supply the processor core voltage at 1.8 V. The Port I/O and RST pins are tolerant of input signals up to 2 V above the VDD supply.

Applications

• Instrumentation panels
  
• Touch panels
  
•  Industrial interface Security
  
•  Residential HVAC
  
• Home appliances
  
• Toys
  
• Keyboards
  
• Fax/printer/scanner front panels