MSP53C691

` Advanced, Catalog Speech Processor for High-Quality Sound, Capable of Unlimited Speech Duration Using External Memory
` Operates up to 12.32 MIPS
` Supports High-Quality Algorithms Such as MELP (1.0 Kbps 3.5 Kbps at 8 kHz), CELP (3.0 Kbps 11.2 kHz at 8 kHz Sampling Rate), ADPCM, Single Channel FM With CELP or MELP
` Speed and Pitch Shifting in MELP for Various Voice Effects
` Six Level Digital Gain Control
` 4 User Configurable I/O's
` Very Low-Power Operation, Ideal for Hand-Held Devices
` Low-Voltage Operation, Sustainable by Three (3) Batteries
` Three Reduced Power Standby Modes, Less Than 10 A in Deep-Sleep Mode
` Resistor-Trimmed Oscillator or 32.768-kHz Crystal Reference Oscillator
` Direct Speaker Drive (32 ) (PDM)
` Interrupt Driven, 4- or 8-Bit Parallel Data Transfer Protocol
`  Available in Die Form or 64-Pin PM Package

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, V_DD (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to 7 V
Supply current, I_DD (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 mA
Input voltage range, V_I (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to V_DD + 0.3 V
Output voltage range, V_O (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to V_DD + 0.3 V
Storage temperature range, T_A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 to 125

† Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTES:
1. Unless otherwise noted, all voltages are measured with respect to V_SS .
2. The total supply current includes the current out of all the I/O pins as well as the operating current of the device.

The MSP53C691 is a standard slave synthesizer from Texas Instruments that accepts compressed speech data from other microprocessors/microcontrollers and converts it to speech. This allows the TI MSP53C691 to be used with a master microprocessor/microcontroller in various speech-related products such as security systems, learning aids, games, and toys. High quality, low bit-rate coders, easy interface with the master microcontroller, digital gain control, low power sleep mode, and low voltage operation makes this MSP53C691 ideal for products requiring long duration speech, less development cycle times, and peripheral device control through the slave device.

This MSP53C691 supports several speech synthesis algorithms that permit tradeoffs to meet the price performance requirements of various markets. The MSP53C691 implements a unique feature of playing a single channel FM music along with CELP or MELP speech data concurrently. This feature allows the user to speak a certain phrase in MELP or CELP with single channel music in the background.

The MSP53C691 is optimized to support a 4-bit wide data transfer protocol. The device has two status bits andthree control bits that control the communication protocol between the master and the slave. The MSP53C691 also has 1 bit (command/data) which differentiates between a command or speech data feeding into the slave.

In 4-bit mode, various commands are sent to the slave during speech to perform various tasks.

The MSP53C691 also supports the 8-bit wide data transfer but the support for commands is disabled during speaking-a-phrase. When speaking-a-phrase in 8-bit mode is complete, the MSP53C691 switches back to the 4-bit mode to receive the next command. Switching between 4-bit mode or 8 bit mode is permitted between speech data files.