Functional Description / User Manual of SIEMENS VDO

Transcription

1 Functional Description / User Manual of SIEMENS VDO Immobilization system smart 451 Type 5WY7776 Name: Department: Telephone: Date: Author: Frank Lindner Check: Thomas Heselberger SV C BC P2 RF Design +49 (941) Revision Responsible Date Description/Changes Valid Frank Lindner More detailed functional description. Explosion view added. Document not yet released by Th. Heselberger loop antenna area added Functional description 5WY7776.doc Page 1 of 7

2 1. FUNCTIONAL DESCRIPTION The immobilizer system consists of an engine control module (ECM), a body controller module ("SAM= Sicherungs- und Ansteuermodul"), the Immobilizer and a key, see Figure 1. The Immobilizer is snapped on to a "SE-Drive Unit" that contains the ignition lock in which the key can be inserted. The Immobilizer is located in the middle console of the vehicle. The Smart Immobilizer is an "active antenna" that contains the following components that are shown in figure 1: 1. Power supply: The voltage regulator is supplied via the SAM with battery voltage (typ. 12V) and supplies the basestation IC (3) with a stable 5V voltage level. 2. Serial interface: This circuitry is used to condition the input and output signals to an external microcontroller via a series of transistors and RC networks. The circuitry has the typical short-circuit and reverse-battery protection. 3. Basestation IC (PCF7991). The Base station IC drives and modulates the LF antenna (4) to supply the transponder in the key with energy and to transmit data to it. It demodulates the answer from the transponder and sends the demodulated signal to the SAM (9) via serial interface (2). The Basestation IC does not contain a control logic. Instead, it is controlled via the SAM (9). 4. LF antenna. The LF ("low frequency, typ. 125 khz") antenna is part of the immobilizer housing and is snapped to a "SE- drive unit" that contains the ignition lock. 5. Antenna circuitry: The antenna circuit is composed of a resonant tank circuitry (resistor, inductor, and capacitor) which is tuned to 125 khz. This portion of the circuit is used to transmit and receive data to and from the transponder. The data is modulated and transmitted at the proper frequency by the basestation IC (3). The tuning components and voltage limiting resistors are assembled on the PCB. 6. Resonator: A 4 MHz resonator is used to provide a clock frequency to the basestation IC. IMMO_PWR GND Power Supply 5V - Regulator (1) Resonator (6) LF Antenna (4) Energy Data (7) Key (8) transpon der IC CAN BD_SERIAL _DATA DI_SCLK (2) Vcc CLK DIN DOUT basestation IC (3) Antenna circuitry (5) Inductive Link f = 125 khz ECM (10) SAM(9) Figure 1 System Overview Functional description 5WY7776.doc Page 2 of 7

3 Components outside of the smart immobilizer are: 7. Transponder coil in the key: This coil is magnetically coupled at 125 khz to the LF antenna (4). 8. Transponder IC in the key. The IC is connected to a parallel resonant circuit formed by the transponder coil (7) and a capacitor. It derives its power supply from the magnetic field established by the immobilizer. The IC provides contactless communication with the immobilizer by demodulating the signals received from the immobilizer and by sending data the immobilizer via ASK (amplitude shift keying) modulation. 9. SAM ("Sicherungs- und Ansteuerungsmodul". This Body controller supplies the immobilizer with battery voltage either via ignition (European SAM variant) or via switched battery voltage (US SAM variant). The SAM contains a microcontroller that controls the complete communication to and from the transponder including cryptology. The SAM communicates with the Engine control module (10) via CANbus. 10. ECM (Engine control module) Functional description 5WY7776.doc Page 3 of 7

4 2. Immobilizer parts The immobilizer consists of the following parts (see explosion view in Figure 2): 1. Housing including LF antenna, pins for the PCB and connector 2. populated PCB 3. cover 4. label. Figure 2) Explosion view of immobilizer Functional description 5WY7776.doc Page 4 of 7

5 3. Technical Data Carrier frequency: 125 khz ± 1.25 khz Carrier field strength: < Modulation: ASK Supply voltage: 12 V Battery type: Car battery Range: < 55mm Loop coil antenna area: m 2 4. Typical usage pattern (for Europe only) 50 immobilizer operations in 24 hours with a typical transmission duration of seconds seconds transmission duration in 24 hours 0.89 seconds transmission in 1 hour Transmitter ON 0.89 seconds / hour Transmitter OFF 3, seconds / hour Duty Cycle: T ON / T (ON+OFF) x 100% = 0.89 / 3,600 x 100 % =0.025 % Functional description 5WY7776.doc Page 5 of 7

6 Label Design Functional description 5WY7776.doc Page 6 of 7

7 5. Label Siemens VDO 5WY7776 IC:267T-5WY7776 Owner Manual: NOTE This device complies with part 15 of the FCC Rules and with RSS -210 of Industry Canada. 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. CAUTION Changes or modifications not expressly approved by the manufacturer could void the user s authority to operate the equipment. Functional description 5WY7776.doc Page 7 of 7