ISD1720PY Multi-Message Voice Record/Playback DIP-28 (ISD1720PY IC)
The ISD1720PY is a high-quality, fully integrated single-chip voice recording and playback device. Part of the ISD1700 series, it is designed for applications where high-quality sound and a robust feature set are required. Housed in a 28-pin DIP package, it features the patented ChipCorder technology, which stores audio in a non-volatile multi-level storage array, allowing for natural-sounding voice and audio reproduction without the need for complex digital-to-analog conversion.
This IC is a popular choice for building voice announcement systems, interactive toys, and alarm systems. It supports both standalone operation (using simple push-button controls) and a SPI (Serial Peripheral Interface) mode for more advanced control via a microcontroller like an Arduino or ATmega.
Key Features
- Adjustable Duration: Provides 12 to 36 seconds of recording time, depending on the chosen sampling frequency (4kHz to 12kHz).
- Dual Operating Modes: Can function in Standalone mode via tactile buttons or SPI mode for sophisticated microcontroller interfacing.
- Non-Volatile Storage: Audio is retained for up to 100 years typical without power, with a life cycle of 100,000 record cycles.
- Integrated Driver: Features a direct speaker drive (PWM) and a separate analog output for external amplification.
- Audio Inputs: Supports both Microphone (with automatic gain control) and Analogue Line-In inputs.
- vAlert Feature: Includes a specialized "voice alert" function to indicate the presence of new recorded messages.
- Wide Voltage Range: Operates reliably on a single supply from 2.4V to 5.5V.
Specifications
- IC Type: Voice Record/Playback
- Sampling Frequency: 4kHz to 12kHz (External resistor controlled)
- Record Time: 20 seconds (at standard 8kHz sampling)
- Flash Memory: Non-volatile multi-level storage
- Output Power: 0.5W into 8 ohms (Direct drive)
- Interface: Push-button or SPI (4-wire)
- Package Type: PDIP-28
- Operating Temperature: 0 to 70 degrees Celsius
Pinout Configuration (28-Pin DIP)
- Pin 1 (VCCD): Digital Power Supply
- Pin 2 (VSSD): Digital Ground
- Pin 3 (VCCA): Analog Power Supply
- Pin 4 (VSSA): Analog Ground
- Pin 5 (SP+): Speaker Output Positive
- Pin 6 (SP-): Speaker Output Negative
- Pin 8 (MIC+): Microphone Input Positive
- Pin 9 (MIC-): Microphone Input Negative
- Pin 10 (ANA IN): Analog Line Input
- Pin 12 (AGC): Automatic Gain Control (Capacitor connection)
- Pin 13 (Analogue Out): Current Output for external amp
- Pin 14 (ROSC): Sampling Frequency adjustment resistor
- Pin 23 (SPI Port): Includes MOSI, MISO, SCLK, and SS/ for MCU control
- Pins 24-28 (Control): Push-button inputs (REC, PLAY, ERASE, FWD, VOL)
