M491B

M491B SINGLE-CHIP VOLTAGE SYNTHESIS TUNING SYSTEM WITH 1 ANALOG CONTROL . . . . . . . . . . . . . . . 16-STATION MEMORY - 7-SEGMENT LED DISPLAY VOLTAGE SYNTHESIZER : 13 BITS 4-BAND PRESET CAPABILITY NON-VOLATILE MEMORY : 304 BITS - 16 WORDS OF 19 BITS FOR TUNING VOLTAGE (13 bits) - BAND (2 bits) - FINE DETUNING (4 bits) - 104 MODIFY CYCLES PER WORD - MIN 10 YEARS DATA RETENTION PCM REMOTE CONTROL RECEIVER : DECODES SIGNAL TRANSMITTED BY M708 VOLUME D/A : 6-BIT RESOLUTION / 8kHz MEMORY SKIP FUNCTION AUTOMATIC SEARCH WITH DIGITAL AFT CONTROL FINE DETUNING D/A ACTING ON AFT DISCRIMINATOR (16 steps) WITH SEPARATE STORAGE FOR EACH MEMORY POSITION. ALTERNATIVELY IT CAN BE USED TO CONTROL BRIGHTNESS OR COLOUR SATURATION MANUAL SEARCH WITH DIGITAL AFT CONTROL MANUAL SEARCH WITH LINEAR AFT SWEEP SEARCH DISPLAY OUTPUT SUPPLY VOLTAGES : VDD = + 5V, VPP = + 25V FOR THE MEMORY CLOCK OSCILLATOR : 445 TO 510kHz INTEGRATED DIGITAL POWER ON RESET (no external initialization circuitry required) tion with the transmitter M708. The highly reliable transmission code ensures error-free signal detection even in presence of high noise conditions. Search of the station is possible in automatic or manual modes. The circuit can operate with a Digital or Linear AFT control. The Digital AFT mode is necessary for automatic search and requires an external circuit (TDA4433 or equivalent, e.g. dual comparator plus TV station detector) to convert the AFC-S-curve into an Up/Down command. Fine tuning (detuni...