The SM1125 series is a multi-melody IC fabricated in NPC’s Molybdenum-gate CMOS process for use in mobile telecommunications equipment. A maximum of 16 melodies can be stored in programmable ROM. The series supports external reference clock input versions and built-in RC oscillator versions, which are set by master-slice option (RC oscillator versions require an external resistor and capacitor). The series supports 12 selectable clock frequencies (fixed for all melodies): external clock input versions support 32.768 kHz, 37.5 kHz, 38.4 kHz and 48.0 kHz systems; built-in oscillator versions support 38.4 kHz, 32.768 kHz, 37.5 kHz and 48.0 kHz. The series supports 2-pin serial data melody selection and 1-pin melody playback control. The series has a power save function, external clock input versions clock gate in no-play modes, built-in RC oscillator versions oscillator stopped in no-play modes. The series uses an 8-pin plastic VSOP package and Molybdenum-gate CMOS process.
The SM1125 series are melody ICs fabricated in Nippon Precision Circuits' Molybdenum-gate CMOS process, designed for use in mobile telecommunications equipment. The devices can store a maximum of 16 melodies with up to 512 steps in programmable ROM. They are available in two versions: external reference clock input and built-in RC oscillator, with selectable clock frequencies ranging from 32.768 kHz to 48.0 kHz.
| Maximum melody selections | 16 |
|---|---|
| Maximum program steps | 512 |
| Supply voltage range (External clock) | 1.5 to 3.6 V |
| Supply voltage range (Built-in RC) | 2.0 to 3.6 V |
| Operating temperature range | -20 to 70 °C |
| Storage temperature range | -40 to 125 °C |
| Package type | 8-pin VSOP |
The external clock input versions operate at 12 selectable frequencies: 32.768/65.536/131.072 kHz, 37.5/75.0/150.0 kHz, 38.4/76.8/153.6 kHz, and 48.0/96.0/192.0 kHz.
Built-in RC oscillator versions operate at 32.768 kHz, 37.5 kHz, 38.4 kHz (standard), and 48.0 kHz.
Playback is controlled by the ST pin; when ST is HIGH, the melody plays repeatedly, and when ST goes LOW, playback stops immediately.