Topics: Power supply, Resistor, Gramophone record Pages: 11 (1628 words) Published: February 27, 2013

Single-Chip Voice Recording & Playback Device for Single 20 to 30 Second Message Features
• Single-chip, high quality voice recording & playback solution

- No external ICs required - Minimum external components
• Non-volatile Flash memory technology

- No battery backup required - 100K record cycles (typical) - 100-year message retention (typical) • Single message of 20 to 30 seconds, with external resistor selection

• User-friendly, easy-to-use operation - Programming & development systems not required - Level-activated recording & edge-activated playback switches • Low power consumption - Operating current: 25 mA (typical, no load) - Standby current: 1uA (typical, no load) • Automatic power-down feature for longer battery life • Chip enable pin for simple message expansion • Single 5 V power supply 6

General Description
The APR9301 de vice offers true single-chip solid-state storage capability and requires no software or microcontroller support. It provides high-quality recording and playback with a single 20- to 30-second message. It is ideal for portable voice recorders, toys, and many other consumer and industrial applications. APLUS integrated analog/multi-level storage technology is implemented in advanced Flash non-volatile memory cells, each of which can typically store more than 256 voltage levels. The APR9301 -V2 stores and reproduces voice signals in their natural forms, eliminating the distortion that is often introduced by encoding and compression. The device combines a small size with low power consumption, nonvolatility, and ease-of-use for a cost effective solution to voice recording and playback. .

Page 1

Functional Block Diagram
Figure 2 shows the functional block diagram for the APR9301-V2


Figure 2 APR9301 -V2 Functional Block Diagram

Power Supplies OscR

Internal O scillator



S w itched C apacitor Filter

S am ple & H old C ircuit

AnaOut MicIn MicRef

A nalog W rite & R ead C ircuits

S w itched C apacitor Filter

N on-Volatile A nalog Storage M em ory A rray



A utom atic G ain C ontrol (A G C )

Device Control

/RecL /PlayE


Sample Application
Figure 3 shows the diagram for a single, 20-second message recording and playback application using theAPR9301 device. When pins are connected as shown in this example, the operating modes are as follows: Record Mode (Level-Activated) A single voice message of up to 20 seconds can be recorded. The /LED pin will go low during the actual recording process to provide a visual indication if an LED light is connected to this pin. The chip is in record mode as long as the /RecL pin stays low (level-activated). If the message lasts longer than 20 seconds, recording will terminate automatically after the last available memory cell is written. If the message is shorter than 20 seconds, the recording operation will stop when the the /RecL pin goes high. The speaker driver is automatically tristated during the recording operation. Messages of up to 30 seconds can be recorded by using different OscR resistor values (see Table 1).

Playback Mode (Edge-Activated) Playback always starts from the beginning of the message. The chip is in playback mode after the /PlayE pin pulses low (edge-activated). Playback will stop immediately when the /PlayE pin pulses low a second time. If the newly recorded message is shorter than the previously recorded message, the remaining portion of the previous message will not be played after the new message is played back. The input preamplifier, AGC, and main amplifier circuits are disabled during playback. Standby Mode (/CE = "0") The chip will automatically return to the standby state after recording or playback operation is completed. Power Down Mode (/CE = "1") The chip is always in standby state. No recording or playback is allowed. Current...
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