ISD1420PI Voice Record/Playback IC Equivalent & Substitute Parts

Part Overview

The ISD1420PI is a ChipCorder® voice record/playback integrated circuit manufactured by Nuvoton Technology Corporation, designed for multiple-message voice recording and playback applications with a 20-second duration capacity. This device features pushbutton interface control, analog microphone input, and PWM speaker output with automatic gain control.

The ISD1420PI is classified as obsolete. Identifying equivalent and substitute parts is necessary to support legacy system maintenance, design updates, and procurement continuity where original components are no longer readily available or production has been discontinued.

Substiute Parts

ISD1420PI

Nuvoton Technology CorporationIn Stock: 1128ISD1420PI Datasheet

Current PartRFQ

ISD1730PY

Nuvoton Technology CorporationIn Stock: 15823ISD1730PY Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ISD1420PI is determined by compatibility across the following critical parameters:

Package and Mounting Compatibility: Both the main part and substitute must use 28-DIP through-hole packaging to ensure direct PCB compatibility without layout modifications.

Functional Interface: The substitute must support pushbutton control interface and maintain analog microphone input capability for signal acquisition.

Output Signal Compatibility: The substitute must provide PWM speaker output or equivalent analog output for audio playback.

Messaging Capability: The substitute must support multiple independent messages, consistent with the original design requirement.

Oscillator Architecture: Internal oscillator type ensures self-contained operation without external timing components.

Automatic Gain Control: This feature must be present in the substitute to maintain consistent audio input levels across varying microphone signal strengths.

Electrical Operating Range: Supply voltage and temperature operating ranges must encompass or exceed the original specifications to ensure functional compatibility in existing applications.

Regulatory Compliance: RoHS and REACH status are evaluated for new designs and system updates requiring modern compliance standards.

Parameter Comparison

Engineering Selection Recommendations

For Legacy System Maintenance: The ISD1420PI remains the direct functional equivalent for existing designs where the 20-second duration and 6.4kHz sampling frequency are specified requirements. Continued sourcing of the ISD1420PI is viable given current inventory availability of 1058 units.

For Design Updates and New Implementations: The ISD1730PY is the active production substitute from Nuvoton Technology Corporation within the ChipCorder® series. This device maintains identical 28-DIP package compatibility and core functional interfaces (pushbutton, microphone input, PWM speaker output) while offering extended capabilities.

Compliance Considerations: The ISD1730PY achieves ROHS3 compliance, making it suitable for applications subject to modern regulatory requirements. The ISD1420PI remains RoHS non-compliant and is appropriate only for legacy system support where compliance exemptions apply.

Operational Range Trade-offs: The ISD1730PY operates across 0°C ~ 70°C, which is narrower than the ISD1420PI's -40°C ~ 85°C range. Applications requiring extended low-temperature operation below 0°C must retain the ISD1420PI or evaluate alternative solutions outside this product family.

Enhanced Features: The ISD1730PY includes volume control in addition to automatic gain control, and supports SPI interface alongside pushbutton control, providing greater design flexibility for new implementations.

Frequently Asked Questions (FAQ)

Q: Can the ISD1730PY directly replace the ISD1420PI in existing PCB designs?

A: Yes, from a physical and electrical interface perspective. Both devices use identical 28-DIP through-hole packaging. The ISD1730PY maintains pushbutton interface control, analog microphone input, and PWM speaker output compatibility. However, verify that your application's operating temperature range does not require operation below 0°C, as the ISD1730PY's minimum operating temperature is 0°C versus the ISD1420PI's -40°C.

Q: What are the key functional differences between these parts?

A: The ISD1730PY extends recording/playback duration to 60 seconds (versus 20 seconds), supports adjustable sampling frequency from 4 ~ 12kHz (versus fixed 6.4kHz), includes volume control capability, and adds SPI interface support. The ISD1420PI provides a narrower operating temperature range of -40°C ~ 85°C.

Q: Are there any supply voltage compatibility issues?

A: The ISD1730PY accepts a wider supply voltage range of 2.4 V ~ 5.5 V compared to the ISD1420PI's 4.5 V ~ 5.5 V. This means the ISD1730PY can operate at lower supply voltages. If your design supplies exactly 4.5 V ~ 5.5 V, both devices are compatible. For supplies below 4.5 V, only the ISD1730PY is suitable.

Q: Does the ISD1730PY require different PCB layout or component support?

A: No. Both devices use the same 28-DIP package footprint and require identical through-hole mounting. No layout modifications are necessary for physical substitution.

Q: Which part should I select for a new design?

A: The ISD1730PY is the recommended choice for new designs. It is in active production status, achieves ROHS3 compliance, and provides extended functionality including variable sampling frequency and volume control. The ISD1420PI should be reserved for legacy system maintenance only.

Q: What is the impact of the different sampling frequencies?

A: The ISD1420PI operates at a fixed 6.4kHz sampling frequency with a 2.6kHz filter pass band. The ISD1730PY supports 4 ~ 12kHz sampling frequency selection. If your application requires the specific 6.4kHz sampling characteristic, verify that the ISD1730PY's adjustable range includes this frequency and that audio quality meets your requirements at this setting.