Laser Virtual Keyboard HT32F2755 Characteristics ® 32-bit ARM Cortex™-M3 Processor Core – up to 72MHz Operation Frequency 128KB Integrated Flash Memory Up to 64KB Integrated SRAM High Speed CMOS Sensor Interface 2 ADC, SPI, I C, GPIO and PDMA Bluetooth interface connected to Smart Phone / Pad Standard QWERTY-keyboard Rechargeable battery using Mini-USB connector Easy-to-use and portable Keyboard Projector CMOS Sensor Application Areas Smart Phone Pad Portable Power Block Diagram Analog Inputs 4 ~ 16MHz 32.768KHz 12‐bit ADC 8 Channels (OPA/CMP) 8MHz HSI HSE Backup Domain 32KHz LSI LSE RTC SPI x 2 / I2C x 2 USART x 2 SPI / I2C / USART Device ISO 7816‐3 x 1 Smart Card CortexTM‐M3 USB 2.0 FS x 1 USB Host HT32F1755/65 MT6573 HT32F2755* CSIF* x 1 CMOS Sensor Flash Memory 128 KB 72 MHz VDD I/O LDO POR WDT LVD BOD 3‐Phase Motor Control Timer x 1 Capture & Compare SRAM 32/64 KB 3‐Phase Brushless Motor PWM Timer x 2 General Purpose Timer x 2 ARM is a registered trademark of ARM Limited in the EU and other countries. Cortex is a trademark of ARM Limited in the EU and other countries.