Miniaturized Surface Mount Hearing Aid

Project Title

Miniaturized Surface Mount Hearing Aid

Project Area of Specialization Electrical/Electronic EngineeringProject Summary

In this project we will be designing a

miniaturized pocket device for hearing

impaired patients. As each individual has

specific range of frequency at which their

hearing response is best. For a healthy person

this range is around 3000Hz- 4000Hz. This

means that when a tone of different frequencies

is heard by an individual with healthy hearing

response. The tone of frequency between

3000Hz – 4000Hz will be easily heard by the

person. The higher we go in frequency the poor

our hearing response becomes at higher

frequencies.

But in the case of hearing impaired patients,

their frequency range is not as same as of

healthy person. Their frequency range for

hearing depends on category of hearing loss

they have whether is mild, moderate, severe or

profound. In this project we will be converting

the frequency of speech signal into best audible

range of patient. The patient will be able to

control the volume of the hearing aid device as

well. A microcontroller will be used for filter

designing, gain controls and automatically

turning on and off the device by detecting the

sound through microphone. The patient will

put on a headphone and can hear the speech

signal clearly

Project Objectives

• Availability of hearing aids for patients at low cost.

• Initiative to make hearing aids in Pakistan.

• To make an easily operatable device.

Project Implementation Method

In this project, firstly some hearing tests have been conducted on patient suffering from severe

hearing loss. Then according to her hearing responses, simulations on Simulink software were

designed using heterodyning of audio frequencies and using bandpass filter and tested on patient.

Further, this project will be designed on hardware and will be tested on patient as well.

Benefits of the Project

The hearing aid devices available in today’s market like Phonak, Siemens, Oticon etc are

basically imported from countries like China, Germany and US. These hearing aids are very

expensive and it is not affordable by every patient suffering from hearing loss. Our project aims

to provide following benefits.

• Cost efficient as compared to hearing aids available in market.

• Helping the community suffering from hearing loss.

• It provides additional feature of sleep mode.

• Introducing the concept of manufacturing hearing aids in Pakistan.

Technical Details of Final Deliverable

This project has several parts, for the purpose of frequency conversion we will be using

concept of heterodyning of audio frequencies.

A local oscillator’s frequency will be

modulated with the input signal coming

through microphone. Local oscillator will have

adjustable frequency. This will resultantly

produce four frequencies, frequency of input

signal, frequency of local oscillator, sum of

these two frequencies and difference of these

two frequencies. Then a bandpass filter will

only pass difference of frequencies which will

be in audible range of patient. Further signal

will be converted in digital domain through

ADC and microcontroller will perform further

processing for filtering, gain adjustments and

automatic on/off control of the device. Then it

will be converted into analog domain through

DAC and will be passed to headphones. 

Final Deliverable of the Project Hardware SystemCore Industry MedicalOther Industries Health Core Technology OthersOther TechnologiesSustainable Development Goals Good Health and Well-Being for PeopleRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	45490
Microphones	Equipment	1	10000	10000
Headphones	Equipment	2	4500	9000
Arduino	Equipment	2	3000	6000
Rechargeable Lithium-ion battery	Equipment	4	2000	8000
Capacitors	Equipment	15	10	150
Resistors	Equipment	15	10	150
Op-amp	Equipment	5	30	150
Potentiometer	Equipment	2	20	40
Breadboard	Equipment	2	1000	2000
Miscellaneous	Miscellaneous	1	10000	10000