A remote keyless entry (RKE) system is designed to lock and unlock vehicle doors remotely.  When a driver pushes a button on a key fob, a transmitter in the fob emits a modulated RF signal.  A vehicle's on-board receiver demodulates the RF signal and provides the demodulated data to a microcontroller.

The TC32306FTG transceiver IC is built on Toshiba's 0.13µm RFCMOS process.  It's suitable for a veriety of remote keyless entry (RKE) applications, including designs requiring 'answerback' functions which detect and transmit vehicle status information.  This high-performance low-power IC will allow automotive OEMs to standardise on a single miniature device.

Remote Keyless Entry (RKE) System Block Diagram

TC32306FTG Features

• QFN Package: 5.3mm x 5.3mm x 0.9mm
• Multi-band (315MHz/434MHz/868MHz/915MHz) operation means TC32306FTG is suitable for global deployment
• Multi-channel fractional PLL operation (5kHz frequency step width) eliminates potential problems with interference from other RF sources by changing frequencies
• FSK and ASK (OOK) modulations operate with supply voltage from 2.0V to 5.5V, featuring a fixed crystal oscillation frequency of 30.32MHz
• Transmit and receive data rates can be set at between 300bps and 10kbps
• Transmitter output is adjustable in steps of approx. 0.5dB from ±0dBm in low-power mode to +10dBm in high-power mode.
• A signal-to-noise and distortion ratio (SINAD) of 12dB ensures very high receiver sensitivity.
• 0.13µm RFCMOS process designed for ultra-low power consumption
• 3.0V operation FSK modulation current: receive 10mA, transmit 12mA
• 3.0V operation ASK modulation current: receive 10mA, transmit 8.5mA
• High-speed response through a quick start-up capability contributes to low average power consumption during daily operation
• Among the on-board functionality offered by the TC32306FTG is an auto signal detector, an RSSI comparator, a digital bit rate filter and a serial control interface for the four-wire SPI interface

Part Number	Intended Use	Applications	TX/ RX	Frequency(Hz)		FSK	ASK	Package	Datasheet
				RF	IF(BW)
TC32306FTG	RKE/ TPMS	Extremely low-power radio	TX/ RX	315 to 915 M	230 kHz / 280 kHz (BW= 320 kHz / 260 kHz)	Y	Y	QFN36