Advancing keyless entry/go
Consumers like the convenience that keyless solutions bring, enabling vehicle entry with seamless
unlock and push-to-start functions. Our dedicated keyless entry/go chipsets, which provide precise
inside/outside detection, are the industry’s top solutions.
NXP keyless
entry/go solutions
ACTIC-Pro features
} Keyless entry/go ICs (PCF7952, PCF7953)
} Low-power, 8-bit microcontroller architecture and 125 kHz 3D-
LF frontend
Benets
} Ultra-low power consumption for long battery life
} Highly integrated for low bill of materials and minimum
board space
} Easy design-in with high LF sensitivity and fast RSSI
Drawing on our world-class experience in car access and
immobilizer solutions, we have developed low-power, highly
integrated keyless entry/go solutions that have a well dened
operating range. These dedicated keyless entry/go ICs
incorporate a highly sensitive 3D LF front-end, a sophisticated
wake-up processor, and an immobilizer and keyless entry
microcontroller. The architecture features a hardware immobilizer
security algorithm and supports the use of Receive Signal
Strength Indication (RSSI) to locate the car key. The ACTIC-Pro
family consisting of PCF7952 and PCF7953 is based on our
eld-proven, low-power 8-bit microcontroller architecture.
Offering several additional features, the next-generation
ACTIC-4G 1D/3D (NCF2952/NCF2951) evolves past its
predecessors.
ACTIC-4G 1D/3D features
} Fourth-generation keyless entry/go IC (NCF2952/NCF2951)
} Increased sensitivity, 3 channel active LF interface for
125 kHz, 1 channel operation, plus passive LF for immobilizer
backup mode
} Low-power 16-bit microcontroller core
} 3D security transponder in NCF2951
} C compiler for facilitated software development
} Memory:
- 2 Kbyte EEPROM
- 16 Kbyte EROM + 8 Kbyte ROM for customer application
- 512 byte RAM
}
Up to 21 I/O ports, including 8 wake-up/button inputs and 2 SPIs
} 3 channel PWM for colored LEDs
} Multi-mode crypto unit supporting standard security up to
high-security, 96-bit and AES-128-bit protocols (compatible
with car access and immobilization portfolio)
} TSSOP38 package
Benets
} New, low-power 16-bit microcontroller core with increased
memory
} Increased LF sensitivity for reduced system cost
} Accelerated inside/outside detection
How does keyless entry/go work?
As the driver enters the operating area of the keyless
entry/go system and places their hand on the door handle,
the car key receives a low-frequency signal from the vehicle
and, if this signal matches the stored data, the key is ‘woken up’.
Once woken, the key analyzes the ‘challenge’ signal from the
vehicle and returns an encrypted ‘response’ signal via the
UHF transmitter. The vehicle then compares the response
with internally stored information and, if authentication is
successful, unlocks the door. Once the driver is inside the car,
the engine can be started by simply pressing the start button.
The system rst checks that the key is inside the car and not
somewhere else, such as on the roof, and then performs the
same authentication procedure when the engine is started.
The combination of LF challenge and UHF response delivers
low power consumption and long battery life. A back-up mode
enables the use of the keyless entry/go system even when the
battery is low, with power being supplied to the key via an
immobilizer basestation.
brb379
IN1P
keyless entry coil and
transponder coil
keyless entry
LF coils
IN1N
P34MSCL
RGB led
P33 P32 P31 P30
P24 buzzer
Li
3 V
CVDDC
NCF2952
UHF TRANSMITTER
OR
UHF TRANSCEIVER
e.g.
PCF790
OR
PQJ7980
IN2P
IN2N
IN3P
IN3N
P10VSSVDDC P11 P12 P13 P20 P21 P22 P23
up to 8 buttons
or spare I/O
MSDA
P17
P16
P15 (XCLK)
4 optional
P14
P27
P26
P25
VBAT
VBATA
VSSA
16 k
USER EROM
8 k
USER ROM
2 k
EEPROM
512 byte
RAM
CALC. UNIT
INTERRUPT
CONTROL
TIMER
MODULATOR
RC
OSCILLATOR
PWM
SPI
ADC
I/O
TEMP
SENSOR
3D ACTIVE AND 1D PASSIVE
CONTACTLESS LF INTERFACE
PRE PROCESSOR
POWER/BATTERY MANAGEMENT
16 Bit RISC
Keyless entry/go system example
ACTIC-4G 1D (NCF2952) block diagram
www.nxp.com
© 2012 NXP Semiconductors N.V.
All rights reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The
information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and
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does not convey nor imply any license under patent- or other industrial or intellectual property rights.
Date of release: April 2012
Document order number: 9397 750 17275
Printed in the Netherlands