Version: 00.02
Date: August 12, 2002
DocId: MC45_HD_01_V00.02a
Status:
PRELIMINARY
General notes
With respect to any damages arising in connection with the described product or this document,
Siemens shall be liable according to the General Conditions on which the delivery of the described
product and this document are based.
This product is not intended for use in life support appliances, devices or systems where a malfunction
of the product can reasonably be expected to result in personal injury. Siemens AG customers using or
selling this product for use in such applications do so at their own risk and agree to fully indemnify
Siemens for any damages resulting from illegal use or resale.
Applications incorporating the described product must be designed to be in accordance with the
technical specifications provided in these guidelines. Failure to comply with any of the required
procedures can result in malfunctions or serious discrepancies in results.
Furthermore, all safety instructions regarding the use of mobile technical systems, including GSM
products, which also apply to cellular phones must be followed.
Handheld applications such as mobile phones or PDAs incorporating the described product must be in
accordance with the guidelines for human exposure to radio frequency energy. The Specific Absorption
Rate (SAR) of the application must be evaluated and approved to be compliant with national and
international safety standards or directives.
Subject to change without notice at any time.
Copyright notice
Copying of this document and giving it to others and the use or communication of the contents thereof,
are forbidden without express authority. Offenders are liable to the payment of damages. All rights
reserved in the event of grant of a patent or the registration of a utility model or design.
Table 33: Voiceband transmit path: Corrected input voltage (peak to peak).
6.6 86 Updated Table 34: Air Interface
8 89 Added ordering information for VOTRONIC handset
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1 Introduction
This document describes the hardware interface of the Siemens MC45 module that connects
to the cellular device application and the air interface. As MC45 is intended to integrate with
a wide range of application platforms, all functional components are described in great detail.
So this guide covers all information you need to design and set up cellular applications
incorporating the MC45 module. It helps you quickly retrieve interface specifications,
electrical and mechanical details and, last but not least, information on the requirements to
be considered for integrating further components.
1.1 Related documents
[1] MC45 AT Command Set for Version 00.02
[2] MC45 GPRS Startup User's Guide (in preparation)
[3] MC45 Remote-SAT User's Guide, as of Version 00.02 (in preparation)
[4] DSB45 Support Box - Evaluation Kit for Siemens Cellular Engines
[5] Application Note 16: Upgrading MC45 Firmware (in preparation)
[6] Application Note 14: Audio and Battery Parameter Download
[7] MC45 Multiplexer User's Guide, as of Version 00.02 (in preparation)
Prior to using the MC45 engines be sure to carefully read and understand the latest product
information provided in the Release Notes (not available for release 00.02.)
To visit the Siemens Website you can use the following link:
http://www.siemens.com/wm
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1.2 Terms and abbreviations
Abbreviation Description
ADC Analog-to-Digital Converter
AFC Automatic Frequency Control
AGC Automatic Gain Control
ARFCN Absolute Radio Frequency Channel Number
ARP Antenna Reference Point
ASIC Application Specific Integrated Circuit
B Thermistor Constant
B2B Board-to-board connector
BER Bit Error Rate
BTS Base Transceiver Station
CB or CBM Cell Broadcast Message
CE Conformité Européene (European Conformity)
CHAP Challenge Handshake Authentication Protocol
CPU Central Processing Unit
CS Coding Scheme
CSD Circuit Switched Data
CTS Clear to Send
DAC Digital-to-Analog Converter
DAI Digital Audio Interface
dBm0 Digital level, 3.14dBm0 corresponds to full scale, see ITU G.711, A-law
DCE Data Communication Equipment (typically modems, e.g. Siemens GSM engine)
DCS 1800 Digital Cellular System, also referred to as PCN
DRX Discontinuous Reception
DSB Development Support Box
DSP Digital Signal Processor
DSR Data Set Ready
DTE Data Terminal Equipment (typically computer, terminal, printer or, for example, GSM
application)
DTR Data Terminal Ready
DTX Discontinuous Transmission
EFR Enhanced Full Rate
EGSM Enhanced GSM
EMC Electromagnetic Compatibility
ESD Electrostatic Discharge
ETS European Telecommunication Standard
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Abbreviation Description
FDMA Frequency Division Multiple Access
FR Full Rate
GMSK Gaussian Minimum Shift Keying
GPRS General Packet Radio Service
GSM Global Standard for Mobile Communications
HiZ High Impedance
HR Half Rate
I/O Input/Output
IC Integrated Circuit
IMEI International Mobile Equipment Identity
ISO International Standards Organization
ITU International Telecommunications Union
kbps kbits per second
LED Light Emitting Diode
Li-Ion Lithium-Ion
Mbps Mbits per second
MMI Man Machine Interface
MO Mobile Originated
MS Mobile Station (GSM engine), also referred to as TE
MSISDN Mobile Station International ISDN number
MT Mobile Terminated
NTC Negative Temperature Coefficient
PA Power Amplifier
PAP Password Authentication Protocol
PBCCH Packet Switched Broadcast Control Channel
PCB Printed Circuit Board
PCL Power Control Level
PCM Pulse Code Modulation
PCN Personal Communications Network, also referred to as DCS 1800
PCS Personal Communication System, also referred to as GSM 1900
PDU Protocol Data Unit
PLL Phase Locked Loop
PPP Point-to-point protocol
PSU Power Supply Unit
R&TTE Radio and Telecommunication Terminal Equipment
RAM Random Access Memory
RF Radio Frequency
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Abbreviation Description
RMS Root Mean Square (value)
ROM Read-only Memory
RTC Real Time Clock
Rx Receive Direction
SAR Specific Absorption Rate
SELV Safety Extra Low Voltage
SIM Subscriber Identification Module
SMS Short Message Service
SRAM Static Random Access Memory
TA Terminal adapter (e.g. GSM engine)
TDMA Time Division Multiple Access
TE Terminal Equipment, also referred to as DTE
Tx Transmit Direction
UART Universal asynchronous receiver-transmitter
URC Unsolicited Result Code
USSD Unstructured Supplementary Service Data
VSWR Voltage Standing Wave Ratio
Phonebook abbreviations
FD SIM fixdialling phonebook
LD SIM last dialling phonebook (list of numbers most recently dialled)
MC Mobile Equipment list of unanswered MT calls (missed calls)
ME Mobile Equipment phonebook
ON Own numbers (MSISDNs) stored on SIM or ME
RC Mobile Equipment list of received calls
SM SIM phonebook
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1.3 Type approval
MC45 is designed to comply with the directives and standards listed below. Please note that
the product is still in a pre-release state and, therefore, type approval and testing procedures
have not yet been completed.
European Directives
99/05/EC Directive of the European Parliament and of the council of 9 March
1999 on radio equipment and telecommunications terminal
equipment and the mutual recognition of their conformity, in short
referred to as R&TTE Directive 1999/5/EC
89/336/EC Directive on electromagnetic compatibility
73/23/EC Directive on electrical equipment designed for use within certain
voltage limits (Low Voltage Directive)
North American Approval
FCC US Equipment Authorization
UL Product Safety Certification
Standards of type approval
ETS 300 607-1 Digital cellular telecommunications system (Phase 2);
Mobile Station (MS) conformance specification;
(equal GSM 11.10-1=>equal 3GPP51.010-1)
ETSI EN 301 511 V7.0.1 (2000-12) Candidate Harmonized European Standard
(Telecommunications series) Global System for Mobile
communications (GSM); Harmonized standard for mobile stations in
the GSM 900 and DCS 1800 bands covering essential requirements
under article 3.2 of the R&TTE directive (1999/5/EC) (GSM 13.11
version 7.0.1 Release 1998)
ETSI EN 301 489-7 V1.1.1 (2000-09) Candidate Harmonized European Standard
(Telecommunications series) Electro Magnetic Compatibility and
Radio spectrum Matters (ERM); Electro Magnetic Compatibility
(EMC) standard for radio equipment and services; Part 7: Specific
conditions for mobile and portable radio and ancillary equipment of
digital cellular radio telecommunications systems (GSM and DCS)
EN 60 950 Safety of information technology equipment (2000)
UL 60 950 Safety requirements
CFR Title 47 Code of Federal Regulations, Part 2 and Part 15
(Telecommunications, PCS)
Requirements of quality
IEC 60068 Environmental testing
DIN EN 60529 IP codes
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SAR requirements specific to handheld mobiles
Mobile phones, PDAs or other handheld transmitters and receivers incorporating a GSM
module must be in accordance with the guidelines for human exposure to radio frequency
energy. This requires the Specific Absorption Rate (SAR) of handheld MC45 based
applications to be evaluated and approved for compliance with national and/or international
regulations.
Since the SAR value varies significantly with the individual product design manufacturers are
advised to submit their product for approval if designed for handheld operation. For
European and US markets the relevant directives are mentioned below. It is the
responsibility of the manufacturer of the final product to verify whether or not further
standards, recommendations of directives are in force outside these areas.
Products intended for sale on US markets
ES 59005/ANSI C95.1 Considerations for evaluation of human exposure to
Electromagnetic Fields (EMFs) from Mobile Telecommunication
Equipment (MTE) in the frequency range 30MHz-6GHz
Products intended for sale on European markets
EN 50360 Product standard to demonstrate the compliance of mobile phones
with the basic restrictions related to human exposure to
electromagnetic fields (300 MHz - 3 GHz)
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1.4 Safety precautions
The following safety precautions must be observed during all phases of the operation,
usage, service or repair of any cellular terminal or mobile incorporating MC45. Manufacturers
of the cellular terminal are advised to convey the following safety information to users and
operating personnel and to incorporate these guidelines into all manuals supplied with the
product. Failure to comply with these precautions violates safety standards of design,
manufacture and intended use of the product. Siemens AG assumes no liability for customer
failure to comply with these precautions.
When in a hospital or other health care facility, observe the restrictions on the
use of mobiles. Switch the cellular terminal or mobile off, if instructed to do so
by the guidelines posted in sensitive areas. Medical equipment may be
sensitive to RF energy.
The operation of cardiac pacemakers, other implanted medical equipment
and hearing aids can be affected by interference from cellular terminals or
mobiles placed close to the device. If in doubt about potential danger, contact
the physician or the manufacturer of the device to verify that the equipment is
properly shielded. Pacemaker patients are advised to keep their hand-held
mobile away from the pacemaker, while it is on.
Switch off the cellular terminal or mobile before boarding an aircraft. Make
sure it cannot be switched on inadvertently. The operation of wireless
appliances in an aircraft is forbidden to prevent interference with
communications systems. Failure to observe these instructions may lead to
the suspension or denial of cellular services to the offender, legal action, or
both.
Do not operate the cellular terminal or mobile in the presence of flammable
gases or fumes. Switch off the cellular terminal when you are near petrol
stations, fuel depots, chemical plants or where blasting operations are in
progress. Operation of any electrical equipment in potentially explosive
atmospheres can constitute a safety hazard.
Your cellular terminal or mobile receives and transmits radio frequency
energy while switched on. Remember that interference can occur if it is used
close to TV sets, radios, computers or inadequately shielded equipment.
Follow any special regulations and always switch off the cellular terminal or
mobile wherever forbidden, or when you suspect that it may cause
interference or danger.
Road safety comes first! Do not use a hand-held cellular terminal or mobile
when driving a vehicle, unless it is securely mounted in a holder for handsfree
operation. Before making a call with a hand-held terminal or mobile, park the
vehicle.
Handsfree devices must be installed by qualified personnel. Faulty installation
or operation can constitute a safety hazard.
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IMPORTANT!
SOS
Compliance with FCC guidelines
Cellular terminals or mobiles operate using radio signals and cellular
networks cannot be guaranteed to connect in all conditions. Therefore, you
should never rely solely upon any wireless device for essential
communications, for example emergency calls.
Remember, in order to make or receive calls, the cellular terminal or mobile
must be switched on and in a service area with adequate cellular signal
strength.
Some networks do not allow for emergency calls if certain network services
or phone features are in use (e.g. lock functions, fixed dialling etc.). You may
need to deactivate those features before you can make an emergency call.
Some networks require that a valid SIM card be properly inserted in the
cellular terminal or mobile.
Fix-mount and mobile devices incorporating MC45 modules must be designed to maintain a
minimum separation distance of 20 cm between the antenna and the end user to satisfy RF
exposure requirements for mobile transmitting devices.
For portable devices incorporating MC45 modules the manufacturer of the final device is
responsible to perform SAR measurements.
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2 Product concept
Designed for use on any GSM network in the world, Siemens MC45 is a tri-band GSM/GPRS
engine that works on the three frequencies GSM 900 MHz, GSM 1800 MHz and GSM
1900 MHz. MC45 features GPRS multislot class 10 and supports the GPRS coding schemes
CS-1, CS-2, CS-3 and CS-4.
To save space on the application platform, MC45 comes as an extremely slim and compact
module. This makes it ideally suited for a broad range of mobile computing devices, such as
laptops, notebooks, multimedia appliances, and particularly offers easy integration with
PDAs, pocket organizers or miniature mobile phones.
The tiny MC45 module incorporates all you need to create high-performance GSM/GPRS
solutions: baseband processor, power supply ASIC, complete radio frequency circuit
including a power amplifier and antenna interface. The power amplifier is directly fed from
the supply voltage BATT+. The MC45 software is residing in a flash memory device. An
additional SRAM enables MC45 to meet the demanding requirements of GPRS connectivity.
The physical interface to the cellular application is made through a board-to-board
connector. It consists of 50 pins, required for controlling the unit, transferring data and audio
signals and providing power supply lines.
MC45 comprises two serial (RS-232) interfaces giving you maximum flexibility for easy
integration with the Man-Machine Interface (MMI).
An extremely versatile audio concept offers various audio interfaces, each available on the
board-to-board connector: a digital audio interface (DAI) and two analog audio interfaces.
This allows you to connect up to three audio devices in any combination, all at the same
time. Using AT commands you can easily switch back and forth and select different audio
modes.
The external dual-band or triple-band antenna can be connected optionally to a connector on
the top side or to a pad on the bottom side.
For battery powered applications, MC45 features a charging control which can be used to
charge a Li-Ion battery. The charging circuit must be implemented outside the module on the
application platform.
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2.1 MC45 key features at a glance
Table 1: MC45 key features
Feature Implementation
Power supply Single supply voltage 3.3V – 4.5V
GSM class Small MS
Frequency bands
Transmit power
GPRS connectivity
Temperature range
Temperature control
and auto switch-off
DATA GPRS:
CSD:
WAP:
· Tri-band EGSM 900, GSM 1800, GSM 1900
· Compliant to GSM Phase 2/2+
· Class 4 (2W) at EGSM900
· Class 1 (1W) at GSM1800 and GSM 1900
· GPRS multi-slot class 10
· GPRS mobile station class B
· Normal operation: -20°C to +55°C
· Restricted operation: -25°C to -20°C and +55°C to +70°C
· Constant temperature control prevents damage from the module when
the specified temperature is exceeded.
· GPRS data downlink transfer: max. 85.6 kbps (see Table 2)
· GPRS data uplink transfer: max. 21.4 kbps (see Table 2)
· Coding scheme: CS-1, CS-2, CS-3 and CS-4
· MC45 supports the two protocols PAP (Password Authentication
Protocol) and CHAP (Challenge Handshake Authentication Protocol)
commonly used for PPP connections.
· Support of Packet Switched Broadcast Control Channel (PBCCH) allows
you to benefit from enhanced GPRS performance when offered by the
network operators.
SIM Application Toolkit Supports SAT class 3, GSM 11.14 Release 98
Real time clock Implemented
Timer function Programmable via AT command
Physical characteristics Size: 53 +0.2 x 34 +0.2 x 3.5+0.3 mm
Firmware upgrade Firmware upgradable over serial interface and SIM interface
Evaluation kit The DSB45 Support Box is an evaluation kit designed to test and type
Supported phonebook types: SM, FD, LD, MC, RC, ON, ME
Weight: 10g
approve Siemens cellular engines and provide a sample configuration for
application engineering. See Chapter 8 for ordering information.
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Table 2: Coding schemes and maximum net data rates over air interface
Coding scheme 1 Timeslot 2 Timeslots 4 Timeslots
CS-1: 9.05 kbps 18.1 kbps 36.2 kbps
CS-2: 13.4 kbps 26.8 kbps 53.6 kbps
CS-3: 15.6 kbps 31.2 kbps 62.4 kbps
CS-4: 21.4 kbps 42.8 kbps 85.6 kbps
Please note that the values stated above are maximum ratings which, in practice, are influenced by a
great variety of factors, primarily, for example, traffic variations and network coverage.
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2.2 Circuit concept
Figure 1 shows a block diagram of the MC45 module and illustrates the major functional
components:
· GSM / GPRS baseband processor
· Power supply ASIC
· Flash
· SRAM
· GSM RF section incl. transceiver and RF power amplifier
MC45 is equipped with a 50-pin 0.5mm pitch board-to-board connector that connects to the
cellular application platform. The host interface incorporates several sub-interfaces
described in the following chapters:
· Power supply and charging control (see Chapters 3.2 and 3.3)
· Dual serial interface (see Chapter 3.5)
· Two analog audio interfaces and a digital audio interface (see Chapter 3.6)
· SIM interface (see Chapter 3.7)
Electrical and mechanical characteristics of the board-to-board connector are specified in
Chapter 5.3. Ordering information for mating connectors and cables are included.
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3.1 Operating modes
The table below briefly summarizes the various operating modes referred to in the following
chapters.
Table 3: Overview of operating modes
Mode Function
Normal operation
GSM / GPRS SLEEP Various powersave modes set with AT+CFUN
command.
Software is active to minimum extent. If the module was
registered to the GSM network in IDLE mode, it is
registered and paging with the BTS in SLEEP mode,
too. Power saving can be chosen at different levels: The
NON-CYCLIC SLEEP mode (AT+CFUN=0) disables the
AT interface. The CYCLIC SLEEP modes AT+CFUN=5,
6, 7 and 8 alternatingly activate and deactivate the AT
interfaces to allow permanent access to all AT
commands.
GSM IDLE Software is active. Once registered to the GSM network,
paging with BTS is carried out. The module is ready to
send and receive.
GSM TALK Connection between two subscribers is in progress.
Power consumption depends on network coverage
individual settings, such as DTX off/on, FR/EFR/HR,
hopping sequences, antenna.
GPRS IDLE Module is ready for GPRS data transfer, but no data is
currently sent or received. Power consumption depends
on network settings and GPRS configuration (e.g.
multislot settings).
GPRS DATA GPRS data transfer in progress. Power consumption
depends on network settings (e.g. power control level),
uplink / downlink data rates and GPRS configuration
(e.g. used multislot settings).
POWER DOWN Normal shutdown after sending the AT^SMSO command.
The Power Supply ASIC (PSU-ASIC) disconnects the supply voltage from the
baseband part of the circuit. Only a voltage regulator in the PSU-ASIC is active
for powering the RTC. Software is not active. The RS-232 interfaces are not
accessible.
Operating voltage (connected to BATT+) remains applied.
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Mode Function
Alarm mode Restricted operation launched by RTC alert function while the module is in
POWER DOWN mode. Module will not be registered to GSM network. Limited
number of AT commands is accessible.
If application is battery powered: No charging functionality in Alarm mode.
Charge-only mode Limited operation for battery powered applications. Enables charging while
module is detached from GSM network. Limited number of AT commands is
accessible. There are several ways to launch Charge-only mode:
· From POWER DOWN mode: Connect charger to the POWER pin of MC45
when engine was powered down by AT^SMSO.
· From Normal mode: Connect charger to the POWER pin of MC45, then
enter AT^SMSO.
Charge mode
during normal
operation
Normal operation (SLEEP, IDLE, TALK, GPRS IDLE, GPRS DATA) and
charging running in parallel. Charge mode changes to Charge-only mode when
the module is powered down before charging has been completed.
See Table 10 and Table 12 for the various options of waking up MC45 and proceeding from one mode
to another.
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3.2 Power supply
The power supply of MC45 has to be a single voltage source of V
= 3.3V...4.5V. It must
BATT+
be able to provide sufficient current in a transmit burst which typically rises to 2A. Beyond
that, the power supply must be able to account for increased current consumption if the
module is exposed to inappropriate conditions, for example antenna mismatch. For further
details see Chapters 3.2.2 and 6.4.1.
All the key functions for supplying power to the device are handled by an ASIC power
supply. The ASIC provides the following features:
· Stabilizes the supply voltages for the GSM baseband using low drop linear voltage
regulators.
· Controls the module's power up and s procedures.
A watchdog logic implemented in the baseband processor periodically sends signals to
the ASIC, allowing it to maintain the supply voltage for all digital MC45 components.
Whenever the watchdog pulses fail to arrive constantly, the module is turned off.
· Delivers, across the VDD pin, a regulated voltage of 2.9V. The output voltage VDD may
be used to supply, for example, an external LED or a level shifter. However, the external
circuitry must not cause any spikes or glitches on voltage VDD. This voltage is not
available in POWER DOWN mode. Therefore, the VDD pin can be used to indicate
whether or not MC45 is in POWER DOWN mode.
· Includes a switch to provide power to the SIM interface.
The RF power amplifier is driven directly from BATT+.
3.2.1 Power supply pins on the board-to-board connector
Five BATT+ pins of the board-to-board connector are dedicated to connect the supply
voltage, five GND pins are recommended for grounding. The POWER and CHARGE pins
serve as control signals for charging a Li-Ion battery. VDDLP can be used to back up the
RTC.
Table 4: Power supply pins of board-to-board connector
Signal name I/O Description Parameter
BATT+ I/O Positive operating voltage
GND - Ground 0 V
POWER I This line signalizes to the
processor that the charger
is connected.
CHARGE O Control signal for external
charging transistor
VDDLP I/O Can be used to back up the
RTC when V
applied.
See Chapter 3.4
BATT+
is not
3.3 V...4.5 V, I
The minimum operating voltage must not fall
below 3.3 V, not even in case of voltage drop.
U
UIN = 2.0 V...5.5 V
Ri = 1kW
I
in,max
OUT,max
= 30µA
< V
£ 2 A during transmit burst
typ
BATT+
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3.2.2 Minimizing power losses
When designing the power supply for your application please pay specific attention to power
losses. Ensure that the input voltage V
even in a transmit burst where current consumption can rise to peaks of 2A. It should be
noted that MC45 switches off when exceeding these limits. Any voltage drops that may occur
in a transmit burst should not exceed 400mV. For further details see Chapter 6.4.
The best approach to reducing voltage drops is to use a board-to-board connection as
recommended, and a low impedance power source. The resistance of the power supply lines
on the host board and of a battery pack should also be considered.
Note: If the application design requires an adapter cable between both board-to-board
connectors, use a flex cable as short as possible in order to minimize power
losses.
Example: If the length of the flex cable reaches the maximum length of 200mm, this
connection may cause, for example, a resistance of 50m! in the BATT+ line and
50m! in the GND line. As a result, a 2A transmit burst would add up to a total
voltage drop of 200mV. Plus, if a battery pack is involved, further losses may
occur due to the resistance across the battery lines and the internal resistance of
the battery.
never drops below 3.3 V on the MC45 board, not
BATT+
BATT+
min. 3.3V
Transmit
burst 2A
Figure 2: Power supply limits during transmit burst
Transmit
burst 2A
max. 400mV
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3.2.3 Charging control
MC45 integrates a charging management for Li-Ion batteries. You can skip this chapter if
charging is not your concern, or if you are not using the implemented charging algorithm.
MC45 has no on-board charging circuit. To benefit from the implemented charging
management you are required to install a charging circuit within your application. In this
case, MC45 needs to be powered from a Li-Ion battery pack, e.g. as specified in Table 6.
The module only delivers, via its POWER line and CHARGE line, the control signals needed
to start and stop the charging process. The charging circuit should include a transistor and
should be designed as illustrated in Figure 3. A list of parts recommended for the external
circuit is given in Table 5.
BATT_TEMP
1
/5 ESDA6V1-5W6
470R
1SS355
BATT+POWER
pcb spark
gap
100nF10k
4V3
SI3441DV
CRS04
3k3
1
/5 ESDA6V1-5W6
CHARGE
Figure 3: Schematic of approved charging transistor, trickle charging and ESD protection
Table 5: Bill of material for external charging circuit