Document
SNC558
Two Channel Direct Drive Speech Controller
1 INTRODUCTION
SNC558 is a two-channel voice synthesizer IC with PWM direct drive circuit. It built-in a 4-bit tiny controller with one 4-bit input port, two 4-bit output ports and three 4-bit I/O ports. By programming through the tiny controller in SNC558, user’s varied applications including voice section combination, key trigger arrangement, output control, and other logic functions can be easily implemented.
2 FEATURES
Single power supply 2.4V – 5.5V 20 seconds voice capacity are provided(@6KHZ sample rate) Built in a 4-bit tiny controller One 4-bit input port, two 4-bit output ports and three 4-bit I/O ports are provided 128*4 bits RAM are provided 64K*10 ROM size are provided for voice data and program Maximum 16k program ROM is provided Readable ROM code data IR carrier signal is provided Built in a high quality speech synthesizer Adaptive playing speed from 2.5k-20kHz is provided Two independent voice channels (Channel 1 + Channel 2→Buo1,Buo2) Built in a PWM Direct Drive circuit and a fixed current D/A output System clock : 2MHz Low Power Reset
Ver: 1.2
1
November 26, 2002
3 Block Diagram
SNC558
Two Channel Direct Drive Speech Controller
ROM
Program/Speech 64K×10 bits
Address Pointers/ STACK
Timing Generator
OSC
SRAM (128 nibbles)
Sampling Rate Counter × 2
PWM
Timer ALU
Voice
Synthesizer
D/A
IO1
IO2
IO3
IO4
IO5
IO6
4 PIN ASSIGNMENT
Symbol P13 ~ P10 P23 ~ P20 P33 ~ P30 P43 ~ P40 P53 ~ P50 P63 ~ P60
VDD GND RST OSC BUO1/VO BUO2
I/O Function Description I Bit3 ~ Bit0 of Input port 1
I/O Bit3 ~ Bit0 of I/O port 2 I/O Bit3 ~ Bit0 of I/O port 3 O Bit3 ~ Bit0 of Output port 4 O Bit3 ~ Bit0 of Output port 5 I/O Bit3 ~ Bit0 of I/O port 6 P Positive power supply P Negative power supply
I Reset pin (active high) O Oscillator / Crystal Out O Positive Output of PWM or DA output O Negative Output of PWM
Ver: 1.2
2
November 26, 2002
SNC558
Two Channel Direct Drive Speech Controller
5 FUNCTION DESCRIPTIONS
5.1. Oscillator
SNC558 accept RC type oscillator for system clock. The typical circuit diagram for oscillator is listed as follow.
OSC
VCC
r
RC Oscillator
5.2. ROM
SNC558 contains substantial 64K words (10-bit) internal ROM. Program, voices and other data are shared with this same 64K words ROM.
5.3. RAM
SNC558 contains 128 nibbles RAM. The 128 nibbles RAM are divided into eight pages (page 0 to page 7, 16 nibble RAM on each page). In our programming structure, users can easily define and locate RAM page in the program. For instance, users can use the instructions, PAGEn (n=0 to 7) to switch and indicate the RAM page. Besides, users can use direct mode, M0 ~ M15 in the data transfer type instructions, to access all 16 nibbles of each page.
5.4. Power Down Mode
“End” instruction will power down SNC558 and enable IC to consume fewer current for power saving. (<3uA @VDD=3V and <5uA @VDD=5V) Please be aware that when the power down mode is activated in SNC558, any valid da.