KT142C Chip – BUSY Pin Idle Voltage Only 0.2V? + Low Power Mode Configuration Guide

 🤖 AI Quick Insight

The BUSY pin on the KT142C chip enters a 2 μA ultra-low-power state about 5 seconds after becoming idle. At this point, the pin goes high-impedance, so a measured voltage of around 0.2 V is normal. If an external amplifier is connected, add a 10 K Ω or 22 K Ω pull-up resistor. Low-power behavior, trigger mode, and volume can be adjusted through the config.txt file.

📘 Overview

This document focuses on the BUSY pin behavior of the KT142C voice playback chip. The BUSY pin corresponds to pin 15 (PA12). During playback, it outputs low level (0 V); when idle, it should output 3.3 V.

However, after 5 seconds of inactivity, the chip automatically enters a 2 μA ultra-low-power mode — in this state, the BUSY pin becomes high-impedance. Consequently, the measured voltage drops to around 0.2 V, which is expected and not a fault.

When connecting to an external power amplifier, you should add a 10 K Ω or 22 K Ω pull-up resistor to ensure stable logic levels.

You can also customize the chip configuration by modifying the config.txt file when connecting the chip to a PC. This file allows you to adjust parameters such as:

Trigger method
Playback volume
BUSY pin polarity
Low-power mode enable/disable (controlled by the 6th parameter in the configuration file)

文章内容

🧩 Key Notes

  1. BUSY pin = PA12 = Pin 15
  2. When controlling an external amplifier:
  3. To disable low-power mode:

✅ Summary The KT142C's BUSY pin voltage of about 0.2 V when idle is normal, not a malfunction. This behavior results from the chip entering 2 μA ultra-low-power mode after 5 seconds of inactivity, during which the BUSY pin is high-impedance. To ensure compatibility with external circuits, add a pull-up resistor, or disable low-power mode through configuration.

文章内容

评论

发表评论

此博客中的热门博文

KT148A Voice Chip at Baidu Baike

图片
Voice Chip The KT148A Sound chip is developed by Shenzhen Qingyue Electronics Co., Ltd. and is widely used in security, transportation, and other fields. The KT148A is a 32-bit DSP voice chip in a standard SOP8 package. It features a built-in 420KByte voice storage space, supporting a maximum voice length of 420 seconds, multi-segment voice playback, direct driving of a 0.5W speaker, and user-replaceable voice content. Chinese Name: KT148A Sound Chip Developer: Shenzhen Qingyue Electronics Co., Ltd. Type: Voice Chip Applications: Security, transportation, and related fields 1. Product Overview The KT148A is a 32-bit DSP sound chip in a standard SOP8 package. It has a built-in 420KByte voice storage space, supporting up to 420 seconds of audio, multi-segment playback, direct driving of a 0.5W speaker, and allows users to replace voice content. 2. Product Advantages Cost Reduction & Reprogrammability: Improved manufacturing processes lower costs while allowing repeated firmware upd...
阅读全文

KT148A Voice Chip Issue: Difficult to Play with Code Sending - Normal Playback After Grounding Pin 4, What’s the Reason?

图片
Problem Description: Hello, we’ve encountered an issue and would appreciate your support: With the KT148A chip, after powering on, sending the code rarely triggers playback. However, if we use tweezers to briefly short Pin 4 (PB0) to ground and then send the code again, playback works normally. What could be causing this? Based on the observed behavior, it’s highly likely an issue with the timing of one-wire communication,  particularly with the start signal, which may be too short.  Let’s analyze this in detail and review the KT148A schematic as follows: 1. Pin 4 (PB0) of the Chip: PB0 is a test pin with the default factory function of triggering wake-up and playback when grounded. 2. Customer Description: When the customer uses tweezers to short PB0 (Pin 4) to ground, it follows this principle. The shorting action actually performs two operations: Action 1: The KT148A detects a falling edge signal, wakes up, exits low-power mode, and enters full-speed operation. Action 2: Th...
阅读全文

KT1025A Dual-Mode Bluetooth Audio Chip Layout Description and Design Precautions

图片
  1. Brief Overview 1. First, please refer to the provided BT201 test DEMO module as the standard. 2. If using the chip independently without testing the BT201 module and directly proceeding to layout, background noise is highly likely if experience is limited. Therefore, always compare with the manufacturer’s test board first. 3. The BT201 solution does not include FM functionality. Please note this. The FM circuit should be left floating without hesitation 2. Precautions 1. Background noise or interference is common in Bluetooth audio products. Do not be careless during layout. 2. If you have not worked on audio products before, study online resources thoroughly. Assuming things casually will naturally lead to noise issues. 3. The core principle is to separate analog ground and digital ground. If unclear, consult an experienced engineer. 4. Ensure a clean power supply. Use an LDO whenever possible instead of a DC-DC converter. 5. Bluetooth operates at high-frequency RF and radiat...
阅读全文