OVERVIEW

The SM1350 series are single-chip high tone quality melody ICs, fabricated using NPC’s Molybdenumgate CMOS process. Melodies are selected in serial or binary (parallel) mode, up to a maximum of 16 melody blocks. There are 4 sound generators incorporated to produce 4 kinds of output tone controlled by 16-tone data, making these ICs ideal for mechanical clocks and similar applications where high tone quality output is demanded.

FEATURES

■ Basic Functions

• 4.0 MHz oscillator frequency

• Power-save function

- Oscillator stopped when no output

- S0 to S3, MODE, LH pull-up resistors open

• BTL or A-class outputs

• Chattering prevention circuit (STN, STOP, S0 to S3)

• 10-bit D/A converter

■ Sound Generator Functions

• DWS (dual wave synthesis) sound generators

• 4 simultaneous sounds for 4 tones

• G2 to F#7 note range

• 16-tone programmable

■ Melody Functions

• Up to 16 programmable melodies (singly or in medleys)

• 1024-step length (notes, rests, jumps, end codes)

• Level hold/one-shot melody modes

• Serial/binary (parallel) select modes

• 4.8 to 605.6 tempo range in 127 steps

• 12 rhythm values

• Ties and slurs programmable

■ Control Signal Outputs

• BUSYN signal LOW during melody output

• CT signal output for external control

■ 2.4 to 5.5 V supply voltage

■ Package

• 24-pin SSOP (SM1350×××)

■ Molybdenum-gate CMOS