RTS8505C

The RTS8505C  is a caller  ID  integrated chip with call waiting  function. An 8-bit microprocessor (6502) has been built  in  the  chip and  it  provides  a  complete  solution  for  the  service of  caller  identification,  especially  for  caller identification on call waiting. The RTS8505C provides all  the  features and  functions offered by  the  former series product RTS8503C, including FSK demodulation, DTMF generation, Ring detection, Power Management and Low battery  indication. In addition,  a highperformance CPE Alerting Tone  (CAS)  detection  is  also performed  in  this single chip. Basically, the chip's CAS performance  is compliant  to  the SR-TSV-0002476  specification. With 32K  ROM,  it can help  the designer easily and  flexibly  to achieve  their desired  features. Up  to 3 sets of additional  I/O  ports  are provided  for  the designer  to  connect  more peripherals  or  other  specified external  circuits.  Up  to  16-degree contrast levels are supported to adjust the LCD contrast. Moreover, the operating voltage is enhanced  to 2.8 Volt for the low power operation. For their applications, it provides a one-chip solution for the adjunct boxes,  feature phones, and other communication systems.