Application of KT148A Voice Chip in Smart Infusion Monitoring Systems

Introduction: When Medical Devices Meet Intelligent Voice Prompts

In modern medical environments, infusion therapy is a common treatment method. However, traditional infusion monitoring primarily relies on medical staff's regular rounds or family members' watch, which is not only inefficient but also poses safety risks. In recent years, with the development of IoT and smart hardware technologies, smart infusion monitoring systems have emerged. These systems typically use sensors to monitor infusion progress in real-time and provide alerts when intervention is needed.

Traditional infusion alarms mostly use buzzers to emit simple alerts. While they serve a reminder function, the amount of information they convey is limited and cannot clearly express specific situations. The introduction of the KT148A voice chip has completely changed this landscape—it replaces monotonous beeps with clear, informative voice prompts, significantly improving user experience and safety.

Technical Analysis of KT148A Voice Chip

Basic Chip Characteristics

KT148A is a 32-bit DSP voice chip in a standard SOP8 package with the following outstanding features:

• Large built-in storage: 420KByte voice storage space, supporting up to 420 seconds of voice duration
• High-quality output: 16-bit PWM output, can directly drive 8 ohm/0.5W speakers
• Flexible control: Supports one-wire serial port control, up to 224 voice addresses
• Low power design: Standby power consumption less than 25μA, ultra-low power mode only 1.7μA
• User programmable: Users can replace voice content themselves via serial port without special programming tools

Core Technical Parameters

Communication Protocol Advantages

KT148A uses a one-wire serial communication protocol, requiring only a single data line to achieve complete control functions:

• 6ms start signal + 8-bit data format
• Pulse width encoding (200us:600us represents 1, 600us:200us represents 0)
• Supports multiple functions such as volume adjustment, combination playback, and loop playback

Implementation in Smart Infusion Monitoring Systems

System Architecture Design

The smart infusion monitoring system consists of the following core components:

1. Drip sensor: Monitors infusion speed and working status in real time
2. Main controller: Processes sensor data and makes judgments
3. KT148A voice module: Receives instructions and plays corresponding voice prompts
4. Wireless communication module (optional): Sends alarm information to the nurse station

Voice Prompt Scenario Design

Based on KT148A's multi-voice segment特性, we designed rich voice prompts for the infusion monitoring system:

// Voice address definition
#define VOICE_MEDICINE_EMPTY   0x01  // "Medicine used up, please add in time"
#define VOICE_ADDITIVE_EMPTY   0x02  // "Additive used up, please add in time"
#define VOICE_QUALITY_CHECKED  0x03  // "Quality inspection completed, start dispensing"
#define VOICE_STOP_MEDICINE    0x04  // "Turn off dispensing machine"
#define VOICE_FLOW_TOO_FAST    0x05  // "Flow rate too fast, please adjust"
#define VOICE_FLOW_TOO_SLOW    0x06  // "Flow rate too slow, please check"
#define VOICE_NEARLY_EMPTY     0x07  // "Infusion nearly completed"
#define VOICE_BUBBLE_DETECTED  0x08  // "Bubble detected, please handle"

// Combination playback example: First play near-completion prompt, then play specific operation guide
void play_nearly_empty_warning(void)
{
    oneline_send_one_data(0xF3);    // Combination playback instruction
    udelay(20000);
    oneline_send_one_data(VOICE_NEARLY_EMPTY);
    udelay(20000);
    oneline_send_one_data(VOICE_PREPARE_CHANGE);
}

Hardware Connection Design

KT148A's connection with the main controller is extremely simple:

Main controller IO ----[1K resistor]---- KT148A PIN3(ONELINE) Main controller IO ----[10K pull-up]--- KT148A PIN2(BUSY) Speaker positive ---- KT148A PIN5(SPK1) Speaker negative ---- KT148A PIN6(SPK2)

Low Power Optimization Strategy

Considering the high requirements of medical devices for battery life, we fully utilize KT148A's low-power characteristics:

// Enter ultra-low power mode when system is idle
void enter_ultra_low_power(void)
{
    oneline_send_one_data(0xF0);  // Enter ultra-low power mode (1.7μA)
}

// Wake up chip
void wake_up_chip(void)
{
    IO1_LOW();    // Pull data line low for 10ms to wake up chip
    udelay(10000);
    IO1_HIGH();   // Release data line
    udelay(30000); // Wait for chip initialization
}

Practical Application Effects and Value

User Experience Improvement

1. Clear information delivery: Compared to traditional buzzers, voice prompts can clearly express problem types and solutions
2. Multi-language support: Can record different language versions according to regional needs
3. Adjustable volume: 15-level volume adjustment to adapt to different environmental needs

Medical Safety Enhancement

1. Timely warning: Abnormal droplets, infusion completion and other situations can get timely reminders
2. Reduce human error: Clear voice instructions reduce the probability of operation errors
3. Reduce medical pressure: Automated prompts reduce the burden of medical staff rounds

Cost-Benefit Analysis

• Hardware cost: KT148A chip itself is low cost, SOP8 package saves PCB space
• Development cost: One-wire serial control greatly simplifies software development difficulty
• Maintenance cost: Voice content can be updated via serial port at any time without replacing hardware

Development Considerations

Voice File Production Suggestions

1. Sampling rate selection: Recommended to use 16KHz sampling rate, balancing sound quality and storage space
2. File optimization: Remove silent parts at the beginning and end of audio to reduce unnecessary storage occupation
3. Format conversion: Use official tools to convert WAV/MP3 to F1A format

Power Design Key Points

1. Lithium battery power supply: Directly connect to PIN8(VBAT), PIN7(VDDIO) needs to be connected to 104 capacitor to ground
2. Dry battery power supply: When voltage is lower than 3.6V, short PIN7 and PIN8
3. Filter capacitor: The power input must add sufficient capacity filter capacitor

Common Problem Handling

1. Download mode entry: Pull PIN5 low during power-on to enter voice download mode
2. Insufficient volume: Check whether the power supply voltage is sufficient, higher voltage can provide greater output power
3. Communication failure: Use logic analyzer to check whether the one-wire serial timing meets requirements

Conclusion

The application of KT148A voice chip in smart infusion monitoring systems fully demonstrates its advantages as a low-cost, high-performance voice solution. By upgrading simple beep alarms to rich voice prompts, it not only improves the product's user experience but more importantly enhances medical safety and reliability.

With the continuous development of medical device intelligence, voice chips like KT148A that are easy to integrate and feature-rich will play important roles in more medical scenarios, contributing technical strength to the digital transformation of the medical industry.

Developers interested in KT148A voice chip are welcome to contact us for complete technical information and development support.

Note: The medical device applications involved in this article need to comply with relevant medical device regulations. Corresponding certification and compliance should be noted in actual product development.