1997 Apr 16

8

Philips Semiconductors

Product specification

8-bit microcontrollers with DTMF generator,

8 kbytes OTP and 128 bytes EEPROM

PCD3755A; PCD3755E;

PCD3755F

Fig.4 Block diagram of the frequency generator and melody output (P1.7/MDY) section.

handbook, full pagewidth

MLC416

HGF REGISTER

MELODY CONTROL

REGISTER

LGF REGISTER

INTERNAL BUS

8

8

8

8

SWITCHED

CAPACITOR

BANDGAP

VOLTAGE

REFERENCE

DIGITAL

SINE WAVE

SYNTHESIZER

DIGITAL

SINE WAVE

SYNTHESIZER

SWITCHED

CAPACITOR

LOW-PASS

FILTER

DAC

DAC

RC LOW-PASS

FILTER

TONE

PORT/MELODY

OUTPUT LOGIC

P1.7/

MDY

square wave