Siemens 5WK4 9046 User manual

Annex No.5
Technical Description
Key 5WK4 9046

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 1of 7
User Manual
of the
Siemens VDO
Remote Control Transmitter
Type:
Designkey

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 2of 7
General description of the Designkey "Keyless Go"
The Designkey incorporates two main functional features.
1. RF remote control system : activation by button press
2. Keyless go system : activation by an external LF-signal source.
In both activation modes the Designkey answers with the available RF (radio
frequency) interface. For remote control function additionally IR (infra red)
communication is in use.
In regular application the RF receiver is located within the control unit which is
mounted in the car interior. The Designkey RF transmitter antenna is
mechanically integrated in the key head. The RF transmitter is used to
transmit different information by a unidirectional transmission line to the RF
receiver within the control unit.
In regular application the following functions are provided by the Designkey :
-Lock the car
-Unlock the car
-Unlock the trunk of the car
-Driverauthentication ( Keyless Go )
-Panic activation ( USA only )
Power supply
The transmitter is provided with 2 Lithium batteries (CR 2025) that both gives
a power supply of +3V.
Buttons
There are three buttons which enable to lock and unlock the doors and to
unlock the trunk and an extra button in case of required panic function (USA
only).
During activation, by button press the microcontroller port is forced to ground
via a “pull-up” within the microcontroller.

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 3of 7
Typical usage pattern (for Europe only)
96 lock/unlock operations in 24 hours with typical transmission duration of 0.8
seconds
→4 lock/unlock operations with one hour
Transmitter ON 3.2 seconds / hour
Transmitter OFF 3,596.8 seconds / hour
Duty Cycle: TON / T (ON+OFF) x 100% = 3.2 / 3,600 x 100 % = 0.08 %

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 4of 7
Block diagrams of the transmitter
µC for
RF Tx and
IR RxTx
data transmission
µC for button
and
LF communication
Button's
Keyless Go -
Control Unit
IR- Transmitter
IR -Receiver
RF transmitter
LED
Power management
Manchester
coded
Battery A
Battery B
standard
µC interface
9,84375 MHz Crystal for 315,0 MHz
13,5687 MHz Crystal for 433.92 MHz
Crystal

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 5of 7
Variants
Model Description
5WK4 9045 433.92 MHz variant for Europe
5WK4 9046 315.00 MHz variant for USA
Technical Data
Carrier frequency model 5WK4 9045: 433.92 MHz ±0.05%
Carrier frequency model 5WK4 9046: 315.00 MHz ±0.05%
Output power model 5KW49045 : < 10 mW
Field strength model 5WK49046 : < 6000µV/m @ 3m
Type of modulation: FSK
Method of frequency generation: PLL
Number of channels: 1
Power supply: battery (2x CR 2025)
Type of battery: lithium
Transmission range: <10 m
NOTE:
Changes or modifications not expressly approved by the manufacturer could
void the users authority to operate the equipment.

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 6of 7
Label design
Europe: (433.92 MHz) USA/CAN: (315 MHz)
Siemens VDO
5WK4 9045
Siemens VDO
5WK4 9046
IC: 267T-5WK4 9046
FCC ID: KR55WK49046
This device complies with part 15 of
the FCC Rules and RSS-210.
Operation is subject to the following
two conditions: (1) This device may
not cause harmful interference, and
(2) this device must accept
interference received, including
interference that may cause
undesired operation.

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc Page 7of 7
Homologation functionality
For homologation use the Designkey samples are programmed with a special
software which allows to set the RF transmission in following modes :
1 ) Constant carrier high frequency
2 ) Constant carrier low frequency
3 ) 1 kBit Modulation
4 ) 10 kBit Modulation
The following diagram shows how to activate the different homologation modes.
OFF
Constant
LOW
FREQ.
(LED Blink
200ms)
Constant
HIGH
FREQ.
(LED Blink
200ms)
Modulated
1kbit/s
(LED Blink
20ms)
Modulated
10
kbit/s
(LED Blink
50ms)
trunk button
any button
open button close or panic or trunk
button
close button
close button
trunk or open or panic
button
any button
panic button
open button