- i - typical applications features description rcr-xxx-rp low cost 315/418/433.92 mhz super-regen ask/ook receiver ? remote keyless entry (rke) ? remote lighting controls ? on-site paging ? asset tracking ? wireless alarm and security systems ? long range rfid ? automated resource management ? low cost ? 3mhz receiving bandwidth ? works with any lc or saw based transmitter ? 5v operation ? 4.5ma current drain ? no external parts are required ? small size: 1.76? x .43? ? 4800 baud operation the rcr-xxx-rp is ideal for short-range remote control applications where cost is a primary concern. the receiver module requires no external rf components except for the antenna. it generates virtually no emissions, making fcc and etsi approvals easy. the super-regenerative design exhibits exceptional sensitivity at a very low cost. a saw filter can be added to the antenna input to improve selectivity for applications that require robust performance. the manufacturing-friendly sip style package and low-cost make the rcr-xxx-rp suitable for high volume applications.
rcr-xxx-rp super-regen ask/ook receiver data sheet - 1 - 5/19/2006 document control created by steve montgomery 5/21/01 engineering review marketing review approved - engineering approved - marketing revision history revision author date description 1.0 sjm 5/21/01 document created 1.1 gwh 7/29/03 updated.
rcr-xxx-rp super-regen ask/ook receiver data sheet - 2 - 5/19/2006 mechanical drawing pinout diagram absolute maximum ratings rating value units power supply and all input pins -0.3 to +12 vdc storage temperature -50 to +100 c soldering temperature (10 sec) 350 c electrical characteristics characteristic symbol min typ max units notes operating voltage v cc 4.5 5.0 5.5 vdc none operating current i cc -- 4.5 -- ma none reception bandwidth bw rx -- 3.0 -- mhz none f c -- 315 -- mhz rcr-315-rp f c -- 418 -- mhz rcr-418-rp center frequency f c -- 433.92 -- mhz rcr-433-rp sensitivity none -- -109 -- dbm none baud rate ? nrz none 1200 -- 4800 bps none baud rate ? pwm none 120 -- 2400 bps none audio bandwidth bw audio .15 -- 2.8 khz none selectivity none tbd tbd tbd operating temperature t op -20 -- +70 c tbd
rcr-xxx-rp super-regen ask/ook receiver data sheet - 3 - 5/19/2006 pin description pin name description 1 ant 50 ? antenna input. 2 gnd receiver ground. connect to ground plane. 3 gnd receiver ground. connect to ground plane. 4,5 v cc (5v) pins 4 and 5 are electrically conne cted and provide operating voltage for the receiver. vcc can be applied to either or both. vcc should be bypassed with a .01 f ceramic capacitor and filtered with a 4.7 f tantalum capacitor. noise on the power supply will degrade receiver sensitivity. 6 analog analog receiver output. this is the audio signal prior to the data slicer. 7 data digital data output. this output is ca pable of driving one ttl or cmos load. it is a cmos compatible output. 8 gnd receiver ground. connect to ground plane theory of operation super-regenerative am detection the rcr-xxx-rp uses a super-regenerative am detector to demodulate the incoming am carrier. a super-regenerative detector is a gain stage with positive feedback greater than unity so that it oscillates. an rc-time constant is included in the gain stag e so that when the gain stage oscillates, the gain will be lower ed over time proportional to t he rc time constant until the oscillation eventually dies. when the oscillation dies, the cu rrent draw of the gain stage de creases, charging the rc circuit, increasing the gain, and ultimately the oscillation st arts again. in this way, the oscillation of the gain stage is turned on and off at a rate set by the rc time constant. this rate is chosen to be super-a udible but much lower than the main oscillation rate. detection is accomplished by measuring the emitter current of the gain stage. any rf input signal at the frequency of the main oscillation will aid the main os cillation in restarting. if the amplitude of the rf input increases, the main oscillation will stay on for a longer period of time, and the emitter current will be higher. therefore, we can detect the original baseband signal by simply low-pass filtering the emitter current. the average emitter current is not very linear as a fu nction of the rf input level. it exhibits a 1/ln response because of the exponent ially rising nature of oscillato r start-up. the steep slope of a logarithm near zero results in high sensitivity to small input signals. data slicer the data slicer converts the baseband analog si gnal from the super-rege nerative detector to a cmos/ttl compatible output. because the data sl icer is ac coupled to the audio output, there is a minimum data rate. ac coupling also limits the minimum and maximum pulse width. typically, data is encoded on the transmit side using pulse-width modulation (pwm) or non- return-to-zero (nrz). the most common source for nrz data is from a uart embedded in a micro-controller. applications that use nrz data encoding typically involve microcontrollers. the most common source for pwm data is from a remote cont rol ic such as the hc-12e from holtek. data is sent as a constant rate square-wave. the duty cycle of t hat square wave will generally be either 33% (a zero) or 66% (a one). the dat a slicer on the rcr-xxx-rp is optimized for use with pwm encoded data, though it will work with nrz data if certain encoding rules are followed.
rcr-xxx-rp super-regen ask/ook receiver data sheet - 4 - 5/19/2006 power supply the rcr-xxx-rp is designed to operate from a 5v power supply. it is crucial that this power supply be very quiet. the power supply should be bypassed using a 0.01uf low-esr ceramic capacitor and a 4.7uf tantalum capacitor. these capacitors should be placed as close to the power pins as possible. the rc r-xxx-rp is designed for continu ous duty operation. from the time power is applied, it can take up to 750msec for the data ouput to become valid. antenna input pin 1 is a 50 ohm antenna input. it will support most antenna types, including printed antennas integrated directly onto the pcb. the performanc e of the different antennas varies. any time a trace is longer than 1/8 th the wavelength of the frequency it is carrying, it should be a 50 ohm microstrip. ordering information product order code rcr-315-rp rcr-315-rp rcr-418-rp rcr-418-rp rcr-433-rp rcr-433-rp radiotronix inc. 905 messenger lane moore, ok 73160 (405) 794-7730 (405) 794-7477 (fax) www.radiotronix.com sales@radiotronix.com
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