Holtek Semiconductor HT37B50
the HT37B70/HT37B50/HT37B30 devices, although mentioned in this datasheet, have already been phased out and are presently no longer available.FEATURES
● Operating voltage: 2.4V~5.5V for HT37B50/30 3.0V~5.5V for HT37B90/70● Operating frequency: 12.8MHz
● Oscillation modes for the oscillator clock fOSC: crystal (12.8MHz) 1-pin RC oscillation typ. 12.8MHz
● Built-in 8-bit MCU (HT-8) with 640´8 or 1280´8 (HT37B90) bits RAM
● Built-in 64K´16-bits to 512K´16-bits ROM for program/data shared
● Two 8 bit timer and one 16 bit timer
● Watchdog timer
● Power-down and Wake-up features for power saving operation
● 16-bit table read instructions for any bank/page read
● Support 32 to 40 bidirectional I/O lines
● Integrated 2-ch stereo 16-bit DAC converter
● 12-level subroutine nesting
● Integrated power amplifier
● Integrated 8-channel 12-bit A/D converter
● 16 channel polyphonic synthesizer
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