Semiconductor devices - Semiconductor interface for human body communication - Part 4: Capsule endoscope

IEC 62779-4:2020 defines general requirements on the electrical performances of a semiconductor interface for capsule endoscope using galvanic coupling human body communication. It includes general and functional specifications of the interface. The semiconductor interface that is covered in this document is the interface to handle or deliver an electrical signal between the capsule endoscope inside the human body and the HBC modem in the receiving device outside the human body.
NOTE Additional information on capsule endoscope using the human body communication is provided in Annex A of this document.

Dispositifs à semiconducteurs - Interface à semiconducteurs pour les communications via le corps humain - Partie 4: Capsule endoscopique

L’IEC 62779-4:2020 définit des exigences générales concernant les performances électriques d’une interface à semiconducteurs pour la capsule endoscopique utilisant les communications via le corps humain par couplage galvanique. Elle inclut des spécifications générales et fonctionnelles de l'interface. L’interface à semiconducteurs couverte dans le présent document est l’interface de traitement ou de fourniture d’un signal électrique entre la capsule endoscopique à l’intérieur du corps humain et le modem HBC du dispositif récepteur à l'extérieur de ce même corps humain.
NOTE L’Annexe A fournit des informations complémentaires concernant la capsule endoscopique utilisant les communications via le corps humain.

General Information

Status
Published
Publication Date
06-Feb-2020
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
07-Feb-2020
Ref Project

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IEC 62779-4
Edition 1.0 2020-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Semiconductor interface for human body
communication –
Part 4: Capsule endoscope
Dispositifs à semiconducteurs – Interface à semiconducteurs
pour les communications via le corps humain –
Partie 4: Capsule endoscopique
IEC 62779-4:2020-02(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62779-4
Edition 1.0 2020-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Semiconductor interface for human body
communication –
Part 4: Capsule endoscope
Dispositifs à semiconducteurs – Interface à semiconducteurs
pour les communications via le corps humain –
Partie 4: Capsule endoscopique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.080.01 ISBN 978-2-8322-7804-8

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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62779-4:2020 © IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms, definitions and letter symbols ............................................................................... 6

3.1 General terms ......................................................................................................... 6

3.2 Rating and characteristics ....................................................................................... 8

3.2.1 Capsule endoscope characteristics .................................................................. 8

3.2.2 Receiving device characteristics ...................................................................... 8

3.2.3 Transfer characteristics ................................................................................... 8

3.3 Letter symbols ...................................................................................................... 10

4 General requirements .................................................................................................... 10

4.1 General specifications ........................................................................................... 10

4.1.1 General ......................................................................................................... 10

4.1.2 Function ........................................................................................................ 10

4.1.3 Implementation types ..................................................................................... 12

4.2 Constructional specifications ................................................................................. 12

4.3 Electrical specifications ......................................................................................... 12

4.3.1 General ......................................................................................................... 12

4.3.2 Power supply characteristics ......................................................................... 12

4.3.3 Power supply type ......................................................................................... 13

4.3.4 Dynamic characteristics of driver in capsule endoscope................................. 13

4.3.5 Dynamic characteristics of analog front end ................................................... 13

4.3.6 CDR circuit interface ...................................................................................... 14

4.3.7 Modem interface ............................................................................................ 14

4.3.8 Limiting values............................................................................................... 14

4.3.9 Temperatures ................................................................................................ 15

4.4 Operating specifications ........................................................................................ 15

4.4.1 Main application ............................................................................................ 15

4.4.2 Compatibility .................................................................................................. 15

Annex A (informative) General description of capsule endoscope using human body

communication ...................................................................................................................... 16

Figure 1 – Definition of cut-off frequency and bandwidth ......................................................... 9

Figure 2 – Typical example of semiconductor interface structure for capsule endoscope

using galvanic coupling human body communication............................................................. 11

Figure 3 – Typical example of data recovery circuit (DRC) .................................................... 12

Figure A.1 – Capsule endoscope application ......................................................................... 17

Table 1 – Letter symbols ....................................................................................................... 10

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IEC 62779-4:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
SEMICONDUCTOR INTERFACE FOR HUMAN BODY COMMUNICATION –
Part 4: Capsule endoscope
FOREWORD

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International Standard IEC 62779-4 has been prepared by IEC technical committee 47:

Semiconductor devices.
The text of this International Standard is based on the following documents:
FDIS Report on voting
47/2600/FDIS 47/2611/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.
---------------------- Page: 5 ----------------------
– 4 – IEC 62779-4:2020 © IEC 2020

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 62779 series, published under the general title Semiconductor

devices – Semiconductor interface for human body communication, can be found on the IEC

website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
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IEC 62779-4:2020 © IEC 2020 – 5 –
INTRODUCTION

IEC 62779-1, IEC 62779-2 and IEC 62779-3 define the general requirements, measurement

method and functional type of a semiconductor interface for human body communication.

They include the general and functional specifications of the interface, the electrical

performances of an electrode, and the operational conditions of the interface. However, an in-

body to on-body channel for a capsule endoscope using galvanic coupling human body

communication (HBC) is different from the channel that is described in IEC 62779-1,

IEC 62779-2 and IEC 62779-3 using capacitive coupling human body communication (i.e.

channel properties, such as signal loss and signal propagation mechanism, are different).

Therefore, the semiconductor interface covered by IEC 62779-1, IEC 62779-2 and

IEC 62779-3 cannot be used for the capsule endoscope using galvanic coupling human body

communication. A common interface for a capsule endoscope using human body

communication should be defined to secure communication compatibility between various

capsule endoscope devices and receiving devices that are implemented on or inside the

human body.
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– 6 – IEC 62779-4:2020 © IEC 2020
SEMICONDUCTOR DEVICES – SEMICONDUCTOR INTERFACE
FOR HUMAN BODY COMMUNICATION –
Part 4: Capsule endoscope
1 Scope

This part of IEC 62779 defines general requirements on the electrical performances of a

semiconductor interface for capsule endoscope using galvanic coupling human body

communication. It includes general and functional specifications of the interface. The

semiconductor interface that is covered in this document is the interface to handle or deliver

an electrical signal between the capsule endoscope inside the human body and the HBC

modem in the receiving device outside the human body.

NOTE Additional information on capsule endoscope using the human body communication is provided in Annex A.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their

content constitutes requirements of this document. For dated references, only the edition

cited applies. For undated references, the latest edition of the referenced document (including

any amendments) applies.

IEEE 802.15.6:2012, IEEE Standard for Local and Metropolitan area networks – Part 15.6:

Wireless Body Area Networks
3 Terms, definitions and letter symbols

For the purposes of this document, the following terms, definitions and letter symbols apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 General terms
3.1.1
transmitting electrode

golden physical structure that transmits an electrical signal from a capsule endoscope to the

human body while typically located inside the human body and adhering to the small bowel

Note 1 to entry: A transmitting electrode delivers an electrical signal to a non-metallic transmission channel, the

human body.
3.1.2
capsule endoscope

small round and tube-shaped fixture that contains a LED module, lens module, sensor PCB,

battery and power module
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IEC 62779-4:2020 © IEC 2020 – 7 –
3.1.3
image sensor

semiconductor device that converts the luminance of light in front of the image sensor to

electrical signal
3.1.4
driver

semiconductor device that delivers image data to the human body in the form of an electrical

signal

Note 1 to entry: The driver is located before the transmitting electrode and outputs the electrical signal with a pre-

limited current and pre-limited voltage.
3.1.5
galvanic coupling human body communication

human body communication method in which a receiver with two electrodes in-body or on-

body can sense the change of electrical current caused by a transmitter through a part of the

human body
3.1.6
capacitive coupling human body communication

human body communication method in which a receiver with an electrode on-body and a

ground off-body can sense the change of electrical potential caused by a transmitter with an

electrode on-body and a ground off-body
3.1.7
receiving electrode

physical metallic structure for receiving an electrical signal from the human body and

delivering the received signal to the analog front end

Note 1 to entry: A receiving electrode delivers an electrical signal from a non-metallic transmission channel, the

human body.
3.1.8
receiving device

electrical device for receiving image data transmitted from a capsule endoscope inside the

human body and storing the received image data in a storage device
Note 1 to entry: The storage device can be a flash memory or hard disk drive.
3.1.9
band-pass filter

semiconductor device or circuit component in an analog front end that eliminates low

frequency noise (i.e. noise from a power line or a fluorescent light) and high frequency noise

(i.e. noise from a radio or a TV broadcasting, a cellular phone) that overlap in a received

signal
3.1.10
analog to digital converter
ADC

semiconductor device or circuit component in an analog front end that converts filtered analog

data to digital data

Note 1 to entry: The converted digital data can be processed in the modem of the receiving device.

3.1.11
data recovery circuit
DRC

semiconductor device or circuit component in an analog front end that recovers a digital data

signal from a filtered signal in the receiving device

Note 1 to entry: The DRC can consist of a comparator and CDR circuit or ADC only.

---------------------- Page: 9 ----------------------
– 8 – IEC 62779-4:2020 © IEC 2020
3.2 Rating and characteristics
3.2.1 Capsule endoscope characteristics
3.2.1.1
single fault current between transmitting electrodes
SFC

maximum amount of short current between the electrodes of the capsule endoscope in the

capsule endoscope semiconductor interface
3.2.1.2
output impedance between transmitting electrodes

impedance seen from the human body into the transmitting electrodes on the capsule

endoscope in the capsule endoscope semiconductor interface

Note 1 to entry The output impedance depends on the output impedances of the driver.

3.2.2 Receiving device characteristics
3.2.2.1
input impedance of receiving electrode

impedance seen from the human body into the receiving electrode of the receiving device in a

capsule endoscope semiconductor interface

Note 1 to entry: The input impedance depends on the input impedances of a band-pass filter and signal amplifier

that are typically the very first stages of an analog front end.
3.2.3 Transfer characteristics
3.2.3.1
input sensitivity of receiving device

minimum signal requirement for the receiving device to recover the transmitted signal from the

capsule endoscope correctly

Note 1 to entry: For the definition of IS the required bit error rate should be satisfied between the capsule

endoscope and the receiving device.
Note 2 to entry: This note applies to the French language only.
3.2.3.2
dynamic range

ratio of a signal’s maximum to minimum voltage ratio at an input of a semiconductor interface

for capsule endoscope human body communication that can be tolerated without signal

distortion

Note 1 to entry: Dynamic range depends on a minimum drive level of a comparator and a signal gain of a signal

amplifier.
Note 2 to entry: This note applies to the French language only.
3.2.3.3
voltage gain

amplifying amount for the amplifier circuit or band-pass filter component in the analog front

end without being attenuated or removed intentionally
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IEC 62779-4:2020 © IEC 2020 – 9 –
3.2.3.4
lower cut-off frequency

lower frequency where a receiving signal is attenuated by 3 dB as passing through a band-

pass filter
SEE: Figure 1.
3.2.3.5
upper cut-off frequency

upper frequency where a receiving signal is attenuated by 3 dB as passing through a band-

pass filter
SEE: Figure 1.
3.2.3.6
bandwidth

frequency width starting from the lower cut-off frequency to upper cut-off frequency without

being attenuated or removed intentionally
Note 1 to entry: This note applies to the French language only.
SEE: Figure 1.
Key
BW f
Bandwidth Lower cut-off frequency
f Upper cut-off frequency
Figure 1 – Definition of cut-off frequency and bandwidth
3.2.3.7
propagation loss

amount of attenuation when a signal transmitted from the capsule endoscope passes through

the human body

Note 1 to entry: Typically propagation loss can be defined as the ratio of the transmitting voltage swing and

received voltage swing.
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– 10 – IEC 62779-4:2020 © IEC 2020
3.2.3.8
lock range
operating frequency range of the CDR where the CDR circuit can be locked
Note 1 to entry: This note applies to the French language only.
3.2.3.9
bit width of ADC
BIT
ADC

output resolution of the ADC which can determine the processing accuracy of the modem in

the receiving device
3.3 Letter symbols
Table 1 – Letter symbols
Name and designation Letter symbol
supply voltage V
operating current I
operating time t
OPC
single fault current between transmitting electrodes I
SFC
output impedance between transmitting electrodes Z
supply voltage V
operating current I
operating time t
OPR
input impedance between receiving electrodes Z
input sensitivity of receiving device IS
dynamic range DR
voltage gain G
lower cut-off frequency
upper cut-off frequency f
bandwidth BW
propagation loss P
lock range LR
bit width of ADC BIT
ADC
4 General requirements
4.1 General specifications
4.1.1 General

Clause 4 provides general specifications to specify the functional and external requirements

for a semiconductor interface for a capsule endoscope using human body communication.

4.1.2 Function
4.1.2.1 Category
If an interface has a functional or electrical category, it shall be stated.
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IEC 62779-4:2020 © IEC 2020 – 11 –
4.1.2.2 Functional description
A general description of the function performed by the interface shall be given.
4.1.2.3 Block diagram

The overall structure of the interface to realize the function shall be given. Details of the

structure shall be given using a block diagram. A semiconductor interface for capsule

endoscope using human body communication consists of a transmitting electrode and

receiving electrode, capsule endoscope (CE), and receiving device (RD). A controller (CTRL)

and driver (DRV) in the capsule endoscope convert the image data into an electrical signal

and send it to the transmitting electrode. The received electrical signal from the human body

is amplified by the signal amplifier (SA), filtered by the band-pass filter (BPF), and processed

by the data recovery circuit (DRC) in an analog front end (AFE). The AFE delivers the

processed data to the modem in the receiving device. (See an example in Figure 2 for more

details.)
Key
CE Capsule endoscope AFE Analog front end
DRV Driver BPF Band-pass filter
CTRL Controller DRC Data recovery circuit
RD Receiving device STG DEV Storage device
SA Signal amplifier TE Transmitting electrode
SB Small bowel RE Receiving electrode
IMGS Image sensor HB Human body
MOD Modem INB Inside of human body
OUTB Outside of human body

NOTE The order of the components in the interface can be changed if necessary, as long as the interface

satisfies the required performances.

Figure 2 – Typical example of semiconductor interface structure for capsule endoscope

using galvanic coupling human body communication

If applicable, control signals that are transmitted between the interface and an HBC modem

shall be defined in the block diagram.

The data recovery circuit (DRC) in the receiving device can be implemented using a

comparator and CDR or it can be implemented using an ADC only. (See an example
in Figure 3 for more details.)
---------------------- Page: 13 ----------------------
– 12 – IEC 62779-4:2020 © IEC 2020
Key
DRC Data recovery circuit CMP Comparator
CDRC Clock and data recovery circuit ADC Analog to digital converter
Figure 3 – Typical example of data recovery circuit (DRC)
4.1.3 Implementation types
4.1.3.1 Manufacturing and assembling technology

The manufacturing technologies for an electrode, for example metallic pattern, thin film, etc.,

an analog front end, for example semiconductor monolithic integrated circuit, thin-film

integrated circuit, hybrid integrated circuit, module, etc., and capsule, for example plastic,

metal, polymer tube, etc., shall be stated. Details of the semiconductor technologies shall be

included.

An assembling technology between the driver and the transmitting electrode, for example

modularization, integration, shall be stated.

An assembling technology between the receiving electrode and the analog front end, for

example modularization, integration, shall be stated.
4.1.3.2 Package technology

The package type, for example ceramic, plastic or glass, shall be given. The package size, for

example length of the capsule, diameter of capsule, should be given.

If applicable, the IEC and/or national reference number of the outline drawing shall be stated.

4.2 Constructional specifications

The physical specifications of an electrode, for example material, dimensions, location, shall

be given. The number of receiving electrodes should be given. The maximum attachable

distance between the receiving electrodes on the skin should be given.
4.3 Electrical specifications
4.3.1 General

The electrical specifications should be given over the specified range of an operating

temperature.
4.3.2 Power supply characteristics
The following characteristics shall be given:
a) supply voltage;
b) operating current.
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