The series of devices are Flash Memory A/D type 8-bit high performance RISC architecture microcontrollers, designed for applications that interface directly to analog signals.

For memory features, the Flash Memory offers users the convenience of multi-programming features. Other memory includes an area of RAM Data Memory as well as an area of true EEPROM memory for storage of non-volatile data such as serial numbers, calibration data etc. By using the In Application Programming technology, user have a convenient means to directly store their measured data in the Flash Program Memory as well as having the ability to easily update their application programs.

Analog features include a multi-channel 10/12-bit A/D converter and an integrated temperature sensor circuitry. Multiple and extremely flexible Timer Modules provide timing, pulse generation and PWM generation functions. Communication with the outside world is catered for by including fully integrated SPI, I²C and UART interface functions, three popular interfaces which provide designers with a means of easy communication with external peripheral hardware. Protective features such as an internal Watchdog Timer, Low Voltage Reset and Low Voltage Detector coupled with excellent noise immunity and ESD protection ensure that reliable operation is maintained in hostile electrical environments.;

A full choice of external, internal high and low speed oscillators is provided including three fully integrated system oscillators which require no external components for their implementation. The ability to operate and switch dynamically between a range of operating modes using different clock sources gives users the ability to optimise microcontroller operation and minimise power consumption.

The inclusion of flexible I/O programming features, 16-bit Cyclic Redundancy Check function and Time Base funcitons along with many other features ensure that the devices will find excellent use in applications such as electronic metering, environmental monitoring in addition to many others.

CPU Features

• Operating voltage
  • MIRC
    • fSYS =64kHz: 1.8V~5.5V
    • fSYS =128kHz: 1.8V~5.5V
    • fSYS =256kHz: 1.8V~5.5V
    • fSYS =512kHz: 1.8V~5.5V
  • HXT
    • fSYS =1MHz: 2.2V~5.5V
    • fSYS =2MHz: 2.2V~5.5V
    • fSYS =4MHz: 2.2V~5.5V
    • fSYS =8MHz: 2.2V~5.5V
    • fSYS =12MHz: 2.7V~5.5V
    • fSYS =16MHz: 3.6V~5.5V
  • HIRC
    • fSYS =2MHz: 1.8V~5.5V
    • fSYS =4MHz: 1.8V~5.5V
    • fSYS =8MHz: 2.2V~5.5V
• Up to 0.25μs instruction cycle with 16MHz system clock at VDD =5V
• Power down and wake-up functions to reduce power consumption
• Low current consumption
  • Under 0.5μA @ 3V current of SLEEP mode, Time Base on and LIRC on
  • Operating current consumption: 350μA @ fSYS =4MHz/3V, HXT on
  • Operating current consumption: 3.8μA @ fSYS =32.768kHz/3V
• Oscillator types
  • External High Speed Crystal – HXT
  • Internal High Speed 2/4/8MHz RC – HIRC
  • Internal Middle Speed 64/128/256/512kHz RC – MIRC
  • External Low Speed 32.768kHz Crystal – LXT
  • Internal Low Speed 32.768kHz RC – LIRC
• Multi-mode operation: FAST, SLOW, IDLE and SLEEP
• Fully integrated internal oscillators require no external components
• All instructions executed in 1~3 instruction cycles
• Table read instructions
• 115 powerful instructions
• 8-level subroutine nesting
• Bit manipulation instruction

Peripheral Features

• Flash Program Memory: 2K×16~8K×16
• Data Memory: 128×8~512×8
• True EEPROM Memory: 128×8~256×8
• In Application Programming function – IAP
• Watchdog Timer function
• Up to 30 bidirectional I/O lines
• Programmable I/O source current for LED driver applications
• Two external interrupt lines shared with I/O pins
• Multiple Timer Modules for time measurement, input capture, compare match output, PWM output function or single pulse output function
• Universal Serial Interface Module – USIM for SPI, I²C or UART communication
• Up to 8 channel 10/12-bit resolution A/D converter
• Temperature Sensor with internal reference voltage
• Integrated 16-bit Cyclic Redundancy Check function – CRC
• Software controlled 4-SCOM line LCD driver with 1/2 bias – Only HT66L2540A/2550A
• Dual Time Base functions for generation of fixed time interrupt signals
• Low voltage reset function
• Low voltage detect function
• Wide range of available package types

Specification:

• max. frequency: 16MHz
• VDD: 1.8V~5.5V
• program memory: 8Kx16
• data memory: 512x8
• data EEPROM: 256x8
• stack: 8
• I/O: 30
• timer: 16-bit PTM×2, 16-bit STMx1
• ADC: 10/12-bitx8
• interface: UART/SPI/I²C×1
• case: 28SSOP