INTRODUCTION
SNC118 is a one-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 I/O ports.
By programming through the tiny controller in SNC118, user’s varied applications including voice section combination, key trigger arrangement, output control, and other logic functions can be easily implemented.

FEATURES
*Single power supply 2.4V – 5.1V
*52 seconds voice capacity are provided(@6KHZ sample rate)
*Built in a 4-bit tiny controller
*One 4-bit input port, two 4-bit I/O ports are provided
*64*4 bits RAM are provided
*160K*10 ROM size are provided for voice data and program
*Maximum 16k program ROM is provided
*Built in a high quality speech synthesizer
*Adaptive playing speed from 2.5k-20kHz is provided
*One voice channel
*Built in a PWM Direct Drive circuit and a fixed current D/A output
*System clock : 2MHz
*Low Power Reset  

SNC118 - One Channel Direct Drive Speech Controller

DESCRIPTION
The Hynix HY57V64420HG is a 67,108,864-bit CMOS Synchronous DRAM, ideally suited for the main memory applications which require large memory density and high bandwidth. HY57V64420HG is organized as 4banks of 4,194,304x4.
HY57V644020HG is offering fully synchronous operation referenced to a positive edge of the clock.
All inputs and outputs are synchronized with the rising edge of the clock input.
The data paths are internally pipelined to achieve very high bandwidth.
All input and output voltage levels are compatible with LVTTL.
Programmable options include the length of pipeline (Read latency of 2 or 3), the number of consecutive read or write cycles initiated by a single control command (Burst length of 1,2,4,8 or Full page), and the burst count sequence(sequential or interleave).
A burst of read or write cycles in progress can be terminated by a burst terminate command or can be interrupted and replaced by a new burst read or write command on any cycle.
(This pipelined design is not restricted by a `2N` rule.)

FEATURES
*Single 3.3±0.3V power supply
*All device pins are compatible with LVTTL interface
*JEDEC standard 400mil 54pin TSOP-II with 0.8mm of pin pitch
*All inputs and outputs referenced to positive edge of system clock
*Data mask function by DQM
*Internal four banks operation
*Auto refresh and self refresh
*4096 refresh cycles / 64ms
*Programmable Burst Length and Burst Type
-1, 2, 4, 8 or Full page for Sequential Burst
-1, 2, 4 or 8 for Interleave Burst
*Programmable CAS Latency ; 2, 3 Clocks

HY57V64420HGT-K
HY57V64420HGT-H
HY57V64420HGT-P
 

HY57V64420HG - 4 Banks x 4M x 4Bit Synchronous DRAM

DESCRIPTION
The MC74VHC244 is an advanced high speed CMOS octal bus buffer fabricated with silicon gate CMOS technology.
It achieves high speed operation similar to equivalent Bipolar Schottky TTL while maintaining CMOS low power dissipation.
The MC74VHC244 is a noninverting 3–state buffer, and has two active–low output enables.
This device is designed to be used with 3–state memory address drivers, etc.
The internal circuit is composed of three stages, including a buffer output which provides high noise immunity and stable output.
The inputs tolerate voltages up to 7V, allowing the interface of 5V systems to 3V systems.

Features
* High Speed: tPD = 3.9ns (Typ) at VCC = 5V
* Low Power Dissipation: ICC = 4mA (Max) at TA = 25°C
* High Noise Immunity: VNIH = VNIL = 28% VCC
* Power Down Protection Provided on Inputs
* Balanced Propagation Delays
* Designed for 2V to 5.5V Operating Range
* Low Noise: VOLP = 0.9V (Max)
* Pin and Function Compatible with Other Standard Logic Families
* Latchup Performance Exceeds 300mA
* ESD Performance: HBM > 2000V; Machine Model > 200V
* Chip Complexity: 136 FETs or 34 Equivalent Gates

MC74VHCXXXDW
MC74VHCXXXDT
MC74VHCXXXM  

MC74VHC244 - Octal Bus Buffer