HopeRF Micro-electronics RF67

The RF67 is a fully integrated transmitter which can operate in the 315, 434, 868 and 915 MHz licence free ISM bands. The transmitter has two modes of operation, a conventional MCU controlled mode and a ‘stand-alone’ mode which enables the RF67 to download configuration and messages from an E²PROM in response to a user input. Stand-alone mode makes the RF67 ideal for miniaturized or low cost remote keyless entry (RKE) applications. It also offers the unique advantage of narrow-band and wide-band communication in a range of modulation formats. The RF67 offers high RF output power and channelized operation suited for the European (ETSI EN 300-220-1), North American (FCC part 15.231, 15.247 and 15.249) and Japanese (ARIB T-67) regulatory standards. The RF67 is a multi-band, single chip transmitter IC capable of (G)FSK, (G)MSK, and OOK modulation of an input data stream. It can transmit this modulated signal in any of the license free ISM bands from 290 MHz to 1020 MHz. The general architecture of the RF67: The frequency synthesizer generating the LO frequency is a third-order fractional-N sigma-delta PLL. The PLL is capable of fast auto-calibration and offers fast switching and settling times. For frequency modulation ((G)FSK and (G)MSK), the modulation is performed within the PLL bandwidth. Optional pre-filtering of the bit stream may also be enabled to reduce the power delivered to adjacent channels. Amplitude modulation (OOK), is performed via a DAC driving the reference of the regulator of the PA. Pre-filtering of the bit stream is also available in this mode. The VCO works at 2, 4 or 6 times the RF output frequency to improve the quadrature precision and reduce pulling effects during transmission. The PA of the RF67 is comprised of two amplifiers - one high power, one low power. This enables the RF67 to deliver a wide range, over 30 dB, of output powers - up to +13 dBm in single PA configuration. However, with an appropriate output impedance transformation, in dual PA mode, this can be increased to +17 dBm. The RF67 also includes two timing references; an RC oscillator, for sleep mode operation of the SPI interface (in MCU mode), and a 32 MHz crystal oscillator, which serves as the low-noise frequency reference of the PLL. The references and supply voltages are provided by the power distribution system which includes several regulators allowing true battery powered operation.

• +17 dBm to -18 dBm Programmable output power.
• Bit rates up to 600 kbits / sec.
• FSK, GFSK, MSK, GMSK and OOK modulation.
• Stand-alone mode: No need for a host MCU.
• Consistent RF performance over a 1.8 to 3.7 V range.
• Low phase noise ( -95 dBc/Hz at 50 kHz ) with automated PLL calibration and fully integrated VCO and loop filter.
• On chip RC timer for timer / wake-up applications.
• Low battery detection.

• Remote Keyless Entry (RKE)
• Remote Control / Security Systems Voice and Data RF Communication Links
• Process and building / home control
• Active RFID
• AMR / AMI Platforms