This information describes the type of component and shall not be considered as assured
characteristics. No responsibility is assumed for possible omissions or inaccuracies. Circuitry
and specifications are subject to change without notice. For the latest product specifications, refer to the EnOcean website: http://www.enocean.com.
As far as patents or other rights of third parties are concerned, liability is only assumed for
modules, not for the described applications, processes and circuits.
EnOcean does not assume responsibility for use of modules described and limits its liability
to the replacement of modules determined to be defective due to workmanship. Devices or
systems containing RF components must meet the essential requirement s of the local le gal
authorities.
The modules must not be used in any relation with equipment that supports, directly or
indirectly, human health or life or with applications that can result in danger for people,
animals or real value.
Components of the modules are considered and should be disposed of as hazardous waste.
Local government regulations are to be observed.
Packing: Please use the recycling operators known to you. By agreement we will take packing material back if it is sorted. You m ust bear the costs of transport. For packing material
that is returned to us unsorted or that we are not obliged to accept, we shall have to invoice you for any costs incurred.
Subject to modifications
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1 GENERAL DESCRIPTION
The extremely power-saving RF transmitter module STM110C from EnOcean enables the
implementation of wireless and maintenance-free sensors. Power supply is provided by a
solar cell. An integrated energy storage allows operation for several days in total darkness.
1.1 Basic Functionality
Three 8-bit A/D converter inputs and 4 digital inputs facilitate multif unctional detector systems, based on passive sensing components. This allows easy and convenient monitoring of
temperature, illumination, etc. – or controlling window and door states – or supervising
input voltages or input currents respectively.
Figure 1: STM110C sensor transmitter module
1.2 Typical Applications
• Building installation
• Industrial automation
• Consumer electronics
The STM110C module serves the 315 MHz air interface protocol of EnOcean. Together with
the transceiver modules TCM200 / TCM210C, this module can be easily integrated into operation and control units for the realization of various application-specific system solutions.
The module is part of a powerful RF system solution from EnOcean for operation and control applications. Because the RF transmitters are self-powered, maintenance-free RF systems can be implemented.
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1.3 Technical Data
Power supply Solar Power Generator (discrete optical cell), or 2.2 - 5.0V external
Frequency / Conducted transmission power 315.0 MHz / 12dBm
Data rate / Modulation type 125 kbps / ASK
Transmission range 300m free field, typ. 30m indoor
Module identifier individual 32-bit ID factory-programmed
EnOcean telegram type 4BS (“Four Byte Sensor”)
Telegram packet length (sub-telegram) 1.2 ms ±5%
No. of (redundant) packets 3 packets within about 40ms, delay effected at random
Input channels 3 x analog inputs (8-bit resolution), 4 x digital inputs
Spontaneous wake-up differential external trigger signal, minimum wake interval 7ms
Cyclic wake-up user-configurable (every 1, 10, 100, or 110 s, tolerance ± 20%)
Redundant retransmission user-configurable, affected at random
Illumination 100 lx up to 100. 00 0 lx
Operation startup time with empty energy store < 10 min @ 400 lx
Operation time during total darkness > 60 h 1)
1)
RF transmission statistically every 17 min, 100s wake-up, temperature 25°C, Goldcap formatted
Ext. power supply output 3.0 V ±3%, 1mA max., ~2.6ms (during wake-up time)
Ext. voltage reference output 2.05V ±3%, 1mA max., ~2.6ms (during wake-up time)
Input sample time after wake-up >1.7 ms
Transmitting indication output (LED) 3.0V ±3%, 2mA max., 3 x 1.2 ms within 40ms
A change of WAKE pin status forces the onboard controller instantly to check all current
analog and digital input values. In addition, a user-programmable cyclic wake-up is provided.
After wake-up, a radio telegram (input data, unique 32-bit sensor ID, checksum) is transmitted in case of a change of any digital input value compared to the last sendin g or in case
of a significant change of measured analog values: >
or >
14LSB of AD_2. In case of a triggered wake-up a radio telegr am is sent in any case.
In case of no relevant input change, a redundant retransmission is sent after a while to
announce all current input values. Between the wake-up phases, the module is in sleep
mode for minimum power consumption.
There is a serial interface which allows to configure several parameters of the module:
- Threshold values of the AD inputs which lead to immediate radio transmission
- Manufacturer code (information about manufacturer and type of device)
In case a manufacturer code is programmed into the module and DI3=0 at wake-up the
module will transmit a dedicated teach-in telegram containing the manufacturer code.
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1.4 Physical Dimensions
Dimensions of PCB 21.0 x 40.0 x 9.0 mm (incl. energy store and wiring pins)
Dimensions of solar cell 35.0 x 13.0 x 1.1 mm (for details see chapter 5)
Antenna pre-installed 15 cm whip antenna
Connector: 20 pins, dual row male, grid 1.27 mm
20
19
2
1
Figure 2
: STM110C package outlines
1.5 Environmental Conditions
Operating temperature -25°C up to + 65 °C
Storage temperature -25°C up to +65 °C
Humidity (PCB) 0% to 95% r.h.
Humidity (Solar cell, rear side) 0% to 60% r.h., no condensate 1)
1)
For corrosion protection, see chapter 3.5
The product life strongly depends on the temperature as the Goldcap used for
energy storage degrades with higher temperature. As a reference the lifetime (capacitance reduced to 70% of nominal value) of the Goldcap is reduced from
100.000 h to 5.000 h when the temperature is raised from 25°C to 65°C.
1.6 Ordering Information
Type EnOcean Ordering Code Radio Frequency Solar Cell
STM110C S3031-D110 315.0 MHz Included
STM111C S3031-D111 315.0 MHz Not included
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2 FUNCTIONAL DESCRIPTION
2.1 Block Diagram
V_SC1
V_SC1
Goldcap
Goldcap
V_SC2
V_SC2
*) DI_xand AD_xinputvalues are transmitted ...
*) DI_x and AD_x input values are transmitted ...
-If wake-upandaninput value has changed
- If wake-up and an input value has changed
-At wake-up and presencesignal time
- At wake-up and presence signal time
RF Transmitter
RF Transmitter
Power, Data*)
Power , Da ta*)
ANT
ANT
(whip)
(whip)
LED
LED
Processor
Processor
Redundant
Redundant
retransmission
retransmission
(every 70th-140th,
(every 70th - 140th,
every 7th -14th,
every 7t h - 14t h,
every cyclicwake-up)
every cycl ic wake-u p)
CP_1CP_0
CP_1CP_0
Digital
Digital
Inputs
Inputs
A/D
A/D
8-bit
8-bit
DI_0
DI_0
DI_1
DI_1
DI_2
DI_2
DI_3
DI_3
AD_0
AD_0
AD_1
AD_1
AD_2
AD_2
WAKE
WAKE
WAKE
WAKE
CW_1
CW_1
CW_0
CW_0
Power control&
Powe r c on t ro l &
wake-up timer
wake -u p timer
Spontaneous
Spontaneous
wake-up
wake-up
Cyclic wake-up
Cyclic wake-up
(every 1,10,100,
(every 1,10, 100,
or 110s)
or 110 s)
Active during
Active during
wake-up only
wake-up only
V_REFV_OUT
V_REFV_OUT
Wake-up
Wake-up
(power on)
(pow er on)
Ready
Ready
(power off)
(power off)
GND
GNDGND
Figure 3: STM110C block diagram
Module power supply
The supplied solar cell has been designed especially for the STM110C for maximum module
performance at smallest dimensions. The active solar area is divided into two to provide
independent module power supplies:
V_SC1: Main power supply input. Must be connected to the STM110C solar cell
(small active area) or by another external energy source respectively
V_SC2: Goldcap charging input by connecting to the STM110C solar cell (big active
area)
The capacitance of the Goldcap may be reduced after long term storage of modules without energy supply. It may take up to one day of charging until the full
capacitance is recovered.
Continuous operation at temperatures higher than 50°C may decrease th e capacitance of the Goldcap. This will result in shorter charging times and shorter operating times in total darkness!
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Power control
The power control supervises V_SC1 supply and charging status of the energy store. It controls the power supply for wake-up timer, microprocessor, HF transmitter and the supply
outputs.
Power supply outputs
Two power supply outputs are available:
a) V_OUT
b) V_REF (stabilized reference voltage)
The outputs are active after wake-up during the active state of the module to drive an external sensor user circuitry.
Wake-up timer
The wake-up timer provides user-programmable wake-up time intervals for activating the
processor and an external wake-up opportunity (WAKE pins).
Features:
Extremely low power consumption during sleeping time period
Cyclic processor wake-up configurable by user through external pin configuration
(CW_0, CW_1)
The sleep mode can be terminated immediately by changing the pin status of the
differential WAKE inputs. Note that the WAKE inputs are part of a special capacitor
circuitry that offers lowest operating power consumption (current flow at switching
over time only).
WAKE and /WAKE always have to be operated via switch-over as shown in the
following:
WAKE
WAKE
WAKE
WAKE
GND
GND
Figure 4: External WAKE pin circuit
A radio telegram is always transmitted after wake-up via WAKE pins!
After transmission the counter for redundant retransmission is reset to a random
number in the confi
ured range.
See chapter 2.5 for configuration of wake-up cycle times.
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Processor
Controls all functionalities after wake-up: First, the values of all measurement inputs are
sampled. After that, RF signal transmission is triggered if one or more of the following conditions are met:
a) One of the input values has changed since the last radio transmission (one of the 4
digital inputs has changed or one of the 3 analog inputs has changed equal to or
more than a defined value of the total measurement range), or
b) Counter for redundant retransmission is elapsed
c) The wake-up has been triggered via the WAKE pins
After every RF transmission, all measurement values are stored for data comparison at
next wake-up time.
See chapter 2.5 for configuration of timing of redundant retransmission.
RF transmitter
The radio transmitter is powered up by the processor when the sending condition is positive. The output LED is activated temporarily during telegram transmission.
Digital inputs are transmitted
within sensor DATA_BYTE0
(least significant 4 bits): DI_0 =
Bit 0, DI_1 = Bit 1, DI_2 = Bit
2, DI_3 = Bit3).
DI_2 and DI_3 are also us ed as
serial interface pins for the configuration of the module. See
page 21.
A signal change of WAKE inputs
stops sleep mode immediately.
A radio telegram is always
transmitted after wake-up via
WAKE pins! (change compared
to STM100!)
Encoding input for processor
wake-up cycle time: 1, 10, 100,
or 110 seconds approximately.
Encoding input for determining
the number of cyclic wake-up
signals that trigger the redun-
Sample moment after wake-up: 1.7 ms …
2.6 ms
Resolution: 8-bit
Input impedance: >100kΩ
(1 bit = V_REF/256 = 8mV
Accuracy vs. V_REF @25°C typ. ±2LSB,
max ±4LSB).
Relevant input change:
> 5 LSB of AD_1
> 6 LSB of AD_0
> 14 LSB of AD_2
These default values may be changed. See
page 23
Sample moment after wake-up: 1.7 ms …
2.6 ms
Real digital TTL input with internal pull-up
(change compared to STM100!)
LOW voltage: <0.45 V
HIGH voltage: > 2.45V
Input impedance >100kΩ
Differential input (capacitive):
- connect to GND via switch
over only
- Resistance to GND < 100 Ω
- Switch over time < 1ms
- Minimum time between wake
signals > 7ms
- Pins should be connected to
V_SC1 if not needed in
application
- max. external allowed leakage
current 100pA
Pins should be left open or connected to
GND
Resistance to GND < 10 Ω
Cyclic wake-up time value strongly depends
on actual power supply voltage and temperature (up to ±20%)
Pins should be left open or connected to
GND
Resistance to GND < 100 Ω
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9
10
11
19
17
8
16
ANT
dant retransmission: Every
Input impedance >100kΩ
wake-up signal, or every 7th 14th, or every 70th - 140th or no
redundant retransmission.
V_OUT Module power supply output
available during wake-up phase
to drive an external sensor cir-
3.0V ±3%, ~2.6ms,
I
= 1 mA max.
Vout
cuitry by the user.
Also used for starting serial
mode.
V_REF Reference voltage output availa-
ble during wake-up phase to
drive an external sensor circuit
2.05 V ±3%, ~2.6ms,
I
= 1 mA max.
Vref
by the user.
LED Output for optional external LED
to indicate every telegram
transmission (short flashing)
3.0 V ±3%, 2 mA max.,
source impedance 470 Ω ±1%,
~3 x 1.2 ms within 40 ms
Also used for starting serial
mode.
V_SC1 Main power supply input. Con-
nect V_SC1 in series with a
Schottky diode of Type BAS 125
When using other energy source than the
supplied solar panel (see chapter 3.6):
2.2 – 5.0 V
to SOL1 of the STM110C solar
cell (smaller area, see Figure 9).
Or connect to another external
energy source respectively.
V_SC2 Goldcap charging input. Connect
V_SC2 in series with a Schottky
For use with the solar cell only (Vo < 5.0 V)!
diode of Type BAS 125 to SOL2
of the STM110C solar cell (bigger area, see Figure 9).
GND
Ground connections
Whip antenna λ/4
Please find recommendations on antenna
mounting in chapter 3.2
Never connect an input (like CP_0..1, AD_0..2, DI_0..3) to a permanent supply
voltage! These inputs should be always left open, connected to GND or connected
to the own V_OUT and / or V_REF (active only during measurement time!). Otherwise they would permanently draw current from the permanent power supply
and could also damage the device (see absolute maximum ratings 2.3 below)
If such a function is absolutely needed, please insert a diode to avoid the problem.
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2.3 Absolute maximum ratings
Symbol Parameter Min Max Units
V_SC1, V_SC2 Input voltage 0 5.5 V
V_SC1 Input current ripple 95 mA
V_SC2 Input current ripple 0.2 A
LED, V_REF,
V_OUT, DI0..3,
AD0..2, CP_0..1
LED, DI0..3,
AD0..2
V_OUT Input voltage while serial mode is active 0 3.09 V
CW_0, CW_1 Input voltage 0 V
WAKE, /WAKE Input voltage 0 V_SC1 V
ANT Input voltage 5 V
V_REF, V_OUT Output current 1 mA
LED Output current 2 mA
V_SC1, V_SC2,
CW_0, CW1,
WAKE, /WAKE,
V_OUT, V_REF,
ANT, GND
CP_0, CP_1, LED,
DI_0..3, AD_0..2
Module Temperature -25 65 °C
Module Humidity 95 % r.h.
Solar cell Illumination 100.000 lx
Solar cell Humidity 60 % r.h.
Exceeding these values may destroy the module!
Input voltage while µC not active (=
0 0.7 V
module completely switched off or sleep
timer running)
Input voltage while µC active 0 V_OUT V
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V_OUT
V_OUT
V_REF
V_REF
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2.5 Encoding Scheme of CW and CP Input Pins
The encoding input pins have to be left open or connected to GND in correspondence with
the following connection schemes:
Wake-up cycle time
CW_0 CW_1 Wake-up cycle time
NC NC 1 sec. ±20%
GND NC 10 sec. ±20%
NC GND 100 sec. ±20%
GND GND 110 sec. ±20%
Redundant retransmission
Via CP_0 and CP_1 an internal counter is set which is decreased at every wake-up signal.
Once the counter reaches zero the redundant retransmission signal is sent.
CP_0 CP_1 Number of wake-ups that
trigger a redundant retransmission
NC NC Every timer wake-up signal
GND NC Every 7th - 14th timer wake-up signal, affected
at random
NC GND Every 70th - 140th timer wake-up signal, affected
at random
GND GND No redundant retransmission
A radio telegram is always transmitted after wake-up via WAKE pins!
After transmission the counter is reset to a random value within the specified interval.
According to FCC 15.231a) a redundant retransmi ssion at every timer wake-up to
determine the system integrity is only allowed in safety and security appli cations!
In this case the total transmission time must not exceed two seconds per hour,
which means that a combination with a 1s wake-up cycle time is not allowed!
If applied in other (non-safety, non-security) applications a minimum of 10s between periodic transmissions is required. In addition the device has to comply with
the lower field strength limits of 15.231e). The limited modular approval of
STM110C is not valid in this case.
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2.6 Solar Energy Balance Calculation
The following diagrams are showing operational performance data of STM110C.
6
5
4
3
Voltage V_SC2[V]
2
1
0
0510152025
charging time [h]
Charging time [h]
Charging at 1000 lx
Charging at 1000 lxCharging at 1000 lx
Charging at 200 lx
Charging at 200 lx
Charging at 50 lx
Charging at 50 lx
Figure 5: Graphs of the goldcap charging process (typ. @25°C). Measured with
white light LEDs, illustration of the illumination level as fluorescent lamp equivalent (EL). Measured with 100s wake up timer.
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In the figure left typical values are shown. In worst case the operating time in
darkness may be 20% less!
2.7 Radio Telegram of STM110C
Frequency range and modu lation scheme
Because of the very low radiated field strength on average, products based on STM110C
(315.0 MHz) can be approved in the USA and in Canada. The approval requirements can be
found in chapter 4 of this paper.
STM110C is based on ASK (amplitude shift keying) modulation with a bit rate of 125 kbit/s.
Telegram content
The payload of the telegram consists of:
8 bit 8 bit 8 bit 4 bit 32 bit
AD_2 AD_1 AD_0 DI_3..0 ID
Transmission timing
The transmission timing of the radio module STM110C has been developed to avoid possible collisions with data packages of other EnOcean transmitters as well as disturbances
from the environment.
With each transmission cycle, 3 identical subtelegrams are transmitted. The transmission of
a subtelegram lasts approximately 1.2 ms. To optimize data security, each telegram is repeated twice within about 40 ms, whereas the delay between the three transmission bursts
is effected at random.
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2.7 Serial Interface for module configuration
It is possible to change some parameters of the module via a serial interface:
- Read / write threshold values of AD_0 to AD_2 which lead to a transmission
of a radio protocol
- Read the firmware version of the module
- Read / write manufacturer ID, device profile and type
The following pins are needed:
- LED
- V_OUT
- DI_3 as USR_RX
- DI_2 as USR_TX
In order to activate the serial mode please take the following steps:
1. Connect LED pin to V_OUT pin
2. Activate STM110C using the timer or the WAKE inputs.
The module will then enter the serial mode. It will receive information via the USR_RX
(DI_3) pin and transmit information via the USR_TX (DI_2) pin. It will not react on WAKE
signals or timer interrupts while in serial mode.
In order to terminate the serial mode the LED pin has to be connected to GND.
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Command list
WR_SYS_AD_THRES
Description:
With this command the user can modify the threshold values at the analog inputs which
lead to a radio transmission. The default values are 6LSB on AD_0, 5LSB on AD_1 and 14
LSB on AD_2.
The module will answer with OK_SYS_WR or ERR_SYS_WR.
A reduction of the thres hold values m ay lead to a higher number of transmissions
and therefore increased energy consumption! The measurement accuracy versus
V_REF is typ. ±2LSB, max ±4LSB!
RD_SYS_MEM
Description:
With this command the user can retrieve all the configuration data from the module.
The module answers with 3 telegrams:
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Command encoding
Bit 7 Bit 0
0xA5
0x5A
0xAB
0x40
0xXX
0xXX
0xXX
0xXX
0xXX
0xXX
0xXX
0xXX
0xXX
ChkSum
0xXX ingored field
INF_SYS_ID_DEV_MAN
Description:
This message contains the manufacturer ID, and the device profile and type.
Command encoding
Bit 7 Bit 0
0xA5
0x5A
0x8B
0x00
DATA_BYTE3
DATA_BYTE2
DATA_BYTE1
0x00
ID_Byte3
ID_Byte2
ID_Byte1
ID_Byte0
0x00
ChkSum
Data_Byte3..0:
Data_Byte3 Data_Byte2 Data_Byte1
7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0
Profile Type Manufacturer ID
ID_Byte3..0:
as follows:
STM110 ID bytes.
In order to prevent fraudulent use, the commands for writing manufacturer ID,
device profile and type to the module are only available to customers signing an
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2.8 Serial Data Reception via Transceiver Modules TCM 200C / TCM 210C
For a detailed description please refer to the User Manual of TCM200C/TCM210C.
Type of STM110C protocol which is seen at the serial outputs of the receiver modules
is “4BS” (4 Byte Sensor):
Description of STM110C radio data content:
ORG = 7 dec. always (EnOcean module type “4BS”)
DATA_BYTE3 = Value of AD_2 analog input
DATA_BYTE2 = Value of AD_1 analog input
DATA_BYTE1 = Value of AD_0 analog input
DATA_BYTE0 = Digital sensor inputs as follows:
Bit 7 Bit 0
In case manufacturer ID, device profile and type have been stored in the module the following telegram will be seen on the TCM200C/TCM210C serial interface if DI_3=0:
Description of STM110C learn telegram:
ORG = 7 dec. always (EnOcean module type “4BS”)
DATA_BYTE0..3 see below
LRN Type = 1
LRN = 0
DI0..DI2: current status of digital inputs
Profile, Type, Manufacturer-ID defined by manufacturer
ID_BYTE3 = module identifier (Byte3)
ID_BYTE2 = module identifier (Byte2)
ID_BYTE1 = module identifier (Byte1)
ID_BYTE0 = module identifier (Byte0)
ORG Data_Byte3 Data_Byte2 Data_Byte1 Data_Byte0 ID
Profile
6 Bit
Type
7 Bit
Manufacturer-ID
11 Bit
LRN Type
1Bit
RE2
1Bit
RE1
1Bit
RE0
1Bit
LRN
1Bit
DI2
1Bit
DI1
1Bit
DI0
1Bit
With this special learn telegram it is possible to identify the manufacturer of a device and
the profile and type of a device. There is a list available describing the function alities of the
respective products. Please contact EnOcean to receive this list.
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3 APPLICATIONS INFORMATION
3.1 Module Mounting
The STM110C module requires some external circuitry configuration and connecting to the
application-specific sensorics circuit. This external circuitry should easily find place on a
small PCB that can be connected upside down to the EnOcean module via the STM dual row
header. This allows the realization of very compact sensor units.
User PCB
User PCB
User PCB
d
d
e
e
r
r
i
i
u
u
q
q
STM
STM
e
e
r
r
110
110
e
e
c
c
Module
Module
a
a
p
p
S
S
User PCB
y
y
s
s
g
g
e
e
r
r
r
r
e
e
o
o
t
t
n
n
s
s
E
E
STM
STM
110
110
Module
Module
9 mm
9 mm
9 mm
9 mm
Figure 7: Examples of compact sensor unit
The following features have to be available on the user PCB:
Power supply by connecting V_SC1 and V_SC2 to the supplied solar cell or by con-
necting V_SC1 to another suitable external energy source
Configuration of the STM firmware by connecting the input pins CW_0..1 and
CP_0..1
If needed, an application-specific sensor circuitry connected to an alog input pin s
(AD_0, AD_1, and/or AD_2) and powered by V_OUT, V_REF and GND
If needed, connections to digital signal inputs DI_0..3. The digital inputs can also
be used for an individual sensor type identification defined by the user.
If needed, a changeover switch connected to the differential WAKE pins for provid-
ing spontaneous wake-up
If needed, a light emitting diode connected between the LED and GND pins for pro-
viding optical feedback of sending
To avoid radio frequency pickup from the environment, st rip lines of the user circuit should be designed as short as possible, and the use of a PCB ground plane
layer is recommended.
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3.2 Antenna Mounting
Positioning and choice of receiver and transmitter antennas are the most important factor
in determining system transmission range. The STM110C transmitter module is supplied
with a soldered whip antenna as standard. By using that antenna, very compact sensor
equipment can be implemented with good radio transmission characteristics. For mounting
the antenna, some notes should be considered to optimize syste m performance:
For best transmitter performance, the space immediately around the antenna has to be
strictly considered, since this has a strong influence on screening and detuning the antenna. The antenna should be drawn out as far as possible and must be never cut off. Mainly
the far end of the wire should be mounted as far as possible away from all metal parts, PCB
strip lines and fast logic components (e.g. the STM microprocessor). Don’t short the whip
λ/4).
(
For a good antenna performance don’t roll up or twist the whip and please draw
attention to an overall whip distance of at least 10 mm (20 mm is better) from
any PCB strip, ground plane and conductive part or electric part.
Note that whip antennas do not show any directional effects under free-field radio-wave
propagation conditions (spot-wise radiator). The RSSI voltage output of the receiver module can be used for evaluating the influence of intuitive RF optimizations.
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3.3 Transmission Range
The main factors that influence the system transmission range are type and location of the
antennas of the receiver and the transmitter, type of terrain and degree of obstruction of
the link path, sources of interference affecting the receiver, and “dead” spots caused by
signal reflections from nearby conductive objects. Since the expected transmission range
strongly depends on this system conditions, range tests should categorically be performed
before notification of a particular range that will be attainable by a particular application.
The following figures for expected transmission range are considered by using a PTM, a
STM or a TCM radio transmitter device and the TCM radio receiver device with preinstalled
whip antenna and may be used as a rough guide only:
Line-of-sight connections:Typically 30m range in corridors, up to 100m in halls
Plasterboard walls / dry wood: Typically 30m range, through max. 5 walls
Brick walls / aerated concrete: Typically 20m range, through max. 3 walls
Ferroconcrete walls / ceilings: Typically 10m range, through max. 1 ceiling
Fire-safety walls, elevator shafts, staircases and supply areas should be
considered as screening.
The angle at which the transmitted signal hits the wall is very important. The effecti v e wall
thickness – and with it the signal attenuation – varies according to this angle. Signals
should be transmitted as directly as possible through the wall. Wall niches should be
avoided. Other factors restricting transmission range:
Switch mounted on metal surfaces (up to 30% loss of transmission range)
Hollow lightweight walls filled with insulating wool on metal foil
False ceilings with panels of metal or carbon fiber
Lead glass or glass with metal coating, steel furniture
The distance between EnOcean receivers and other transmitting devices such as computers, audio and video equipment that also emit high-frequency signals should be at least
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3.4 Connecting the solar cell
The supplied solar cell has been designed especially for maximum module performance at
smallest dimensions. The active solar area is divided into two to provide independent module power supplies:
V_SC1: Main power supply input. Must be connected to the small active area of the
solar cell or to another external energy source respectively
V_SC2: Goldcap charging input. Must be connected to big active area of solar cell
The solar cell must be connected to the module in series with Schottky Diodes of type
BAS 125. In Figure 9 the dual diode BAS 125-07 (SMD, parallel pair) is used.
For outdoor use in addition the BZX84-B5V1 diodes (leakage current at 2V must
be below 2µA) are needed to avoid damage of the module by over voltage.
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3.5 Solar Cell Handling, Soldering & Mounting
The EnOcean solar cell technology guarantees the highest stabilized efficiency values. At
the front, the solar modules have a glass covering that protects the photovoltaic layer from
the effects of the environment and weather. The rear features contacts for the electrical
connection.
Handling
Prevent injuries due to the sharp glass edges.
Always handle the modules carefully, avoid damage of the glass edges that leads to
glass breakage or glass chips. The layers are sensitive to punctual pressure, scratching or grinding. During handling and processing, always make sure that no particles are pushed into the coating. Scratches, i mprints or particles pushed into the
layer can lead to short-circuiting of the module, thus deterioration.
The processing of the modules with lacquer spray process es or edge grinding could
lead to an impairment of the electrical function of the module (electrostatic influences).
In case of necessary module cleaning, the following cleaning agents are suggested:
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(a) In Pb alloy soldering, the soldering iron shall be set up and stabilized
at 240°C before and in the calibration. For Pb-free solder wire, the soldering iron shall be set up and stabilized at 255°C before and in the
calibration.
(b) Take little solder wire on the solderin g iron tip and put the tip in con-
tact with the contact-pad of the temperature meter for 1 minute.
(c) Temperature shown on the temperature meter shall be 255°C (Pb-
free) at least for one minute otherwise re-adjust the temperature setting of the soldering iron.
Soldering operation
Step 1: Make soldering iron tip and solder wire contact with the copper paste
of solar cell together. At this moment, tin pot formed in a shape of
half ball type or makes a plane type on the copper paste. All the
processes shall be well done less than 2 seconds.
Step 2: Melt solder wire on the top of solder lead wire. Weld the tin pot
again and put the lead wire into the inside of tin pot. Take off the
solder iron tip. Finish this step within 2 second also.
Soldering operation on the solar cell shall be non-destructive. At any time, only
make the soldering iron tip contact the copper paste of the solar cell less than
2 seconds.
Attention
o Hold the soldering iron at an angle of 30° to 45° with the solar cell in the
welding process
o Lead wire is in the contact with the copper paste at an angle of 15°
o Make sure the welding process not more than the time limit and th e l ead
wire in good contact with copper paste through the solder. Please watch
out the loose contact between the lead wire and the copper paste if any
o Do not move the lead wires and solar cell before cooling the tin pots
o Weld soldering is always with smooth surface and with shine.
Test criteria
o Pull strength in vertical direction: more than 500 gram
o Pull strength in horizontal direction: more than 200 gram
Note 1: For pull strength test, the lead wire used should be 28-30 AWG multi-
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Corrosion protection
Corrosion protection is essential to the lifetime of the solar module. The solar module is
extremely resistant to temperature effects. But mounting must particularly provide protection against humidity. The proper choice of suitable sealing material is important.
The best method is protection by a transparent cover, mainly important for outdoor applications. Also well-suited is a casing by silicone (not acrylic!). With every kind of protection
solution, it is very important that the cell edges and the metallic contact areas are covered.
Figure 11: Examples of solar cell mounting
Shade
During installation, care should be taken to ensure that the active photovoltaic area is not
shaded. The cells (strips), which produce the least current due to shade, determine the
total module current.
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3.6 Using an Alternative Power Supply, e.g. Battery
Alternatively to the use of the supplied solar cell, the module power supply input V_SC1 can
be driven by another suitable external energy source.
The external energy source must fulfill the following requirements:
Parameter Min Typ Max Unit
Open circuit voltage 2.2 5.0 V
Ampacity (Peak) 10 mA
Ampacity (continuous) 1 µA
When using a battery please take care that the transistion resistance between battery and battery holder is << 10Ω to avoid voltage drop!
Wrong polarity will damage the module!
3.7 Learn Push Button
There are two fundamental methods for transmitter assignments to a receiver:
1.) Manual input of the transmitter ID into the receiver system
2.) The receiver systems automatically learns the ID of a received radio telegram by a
special teach-in routine
In the second case please note that cyclic sending sensors can be unintentionally learned,
mainly if there are some sensors in operation at the same time. Because of that it is recommended to implement a learn procedure that is reacting to a dedicated “Learn Telegram”
only. This special learn procedure has to be realized by the system intelligence after
TCM200C/TCM210C serial interface. For example this can be realized as follows.
Recommendation for the realization of a learn push button:
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4 AGENCY CERTIFICATIONS
4.1 FCC (United States) Certification
STM110C LIMITED MODULAR APPROVAL
This is an RF module approved for Limited Modular use operating as an intentional transmitting device with respect to 47 CFR 15.231(a-c) and is limited to OEM installation. The
module is optimized to oper ate using small amounts of harvested energy, such as can be
collected by a small solar cell exposed to ambient light. The module transmits short radio
packets comprised of control signals, (in some cases the control signal may be accompanied with data) such as those used with alarm systems, door openers, remote switches,
and the like. The module does not support continuous streaming of voice, video, or any
other forms of streaming data; it sends only short packets containing control signals and
possibly data and is typically powered by a solar cell in ambient li ght. The module is designed to comply with, has been tested according to 15.231(a-c), and has been found to
comply with each requirement. Thus, a finished device containing the STM110C radio module can be operated in the United States without additional Part 15 FCC approval (approval(s) for unintentional radiators may be required for the OEM’s finished product), under
EnOcean’s FC C ID num be r. Thi s gr ea tly sim pli fies and shortens the design cycle and development costs for OEM integrators.
The module can be triggered manually or automatically, which cases are described below.
Manual Activation
The radio module can be configured to transmit a short packetized control signal if
triggered manually. The module can be triggered, by pre ssing a switch, for example. The packet contains one (or more) control signals that is(are) intended to control something at the receiving end. The packet may also contain data. Depending
on how much energy is available from the energy source, subsequent manual triggers can initiate the transmission of additional control signals. This may be necessary if prior packet(s) was(were) lost to fading or interference. Subsequent triggers
can also be initiated as a precaution if any doubt exists that the first packet didn’t
arrive at the receiver. Each packet that is transmitted, regardless of whether it was
the first one or a subsequent one, will only be transmitted if enough energy is available from the energy source.
Automatic Activation
The radio module also can be configured to transmit a short packetized control signal if triggered automatically, by a relevant change of its inputs, for example.
Again, the packet contains a control signal that is intended to control something at
the receiving end and may also contain data. As above, it is possible for the packet
to get lost and never reach the receiver. However, if enough energy is available
from the energy source, and the module has been configured to do so, then another
packet or packets containing the control signal may be transmitted at a later, unpredictable time.
OEM Requirements
In order to use EnOcean’s FCC ID number, the OEM must ensure that the following conditions are met.
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End users of products, which contain the module must not have the ability to alter the
firmware that governs the operation of the module. The agency grant is valid only when
the module is incorporated into a final product by OEM integrators.
The end-user must not be provided with instructions to remove, adjust or install the
module.
The Original Equipment Manufacturer (OEM) must ensure that FCC labeling requirements
are met. This includes a clearly visible label on the outside of the final product. Attaching a label to a removable portion of the final product, such as a ba ttery cover, is not
permitted. The label must include the following text:
Contains FCC ID: SZV-STM110C
The enclosed device complies with Part 15 of the FCC Rules. Operation is
subject to the following two conditions: (i.) this device may not cause
harmful interference and (ii.) this devi ce must accept any interference received, including interference that may cause undesired operation.
The user manual for the end product must also contain the text given above.
Changes or modifications not expressly approved by EnOcean could void the user's au-
thority to operate the equipment.
The module must be used wit h o nl y the f ollowing approved antenna(s).
Part Number Type Gain
N.A. Integrated Wire/Monopole 1.0 dBi
4.2 IC (Industry Canada) Certification
Labeling requirements for Industry Canada are similar to those required by the FCC. The
Original Equipment Manufacturer (OEM) must ensure that IC labeling requirements are
met. A clearly visible label on the outside of a non-removable part of the final product must
include the following text: