Radiometrix Hartcran House, 231 Kenton Lane, Harrow, HA3 8RP, England Tel: +44 (0) 20 8909 9595, Fax: +44 (0) 20 8909 2233 RX3G Issue 2, 13 November 2012 UHF FM receiver module with RSSI The RX3G is a PLL synthesiser based miniature PCB mounting UHF radio data receiver. With the matching TX3B-869-64 transmitters, RX3G allows the simple implementation of wireless data links at speeds up to 64kbps and distances up to 75 metres in-building or 300 metres over open ground. Fig 1: RX3G-869.85-64 Features: Designed to comply with harmonised radio standard EN 300 220-3 Designed to comply with harmonised EMC standard EN 301 489-3 North American version conforms to FCC part 15.249 Data rates up to 128kbps Usable range up to 300m Versions available on 868.3MHz, 869.5MHz, 869.85MHzn and Regulated and Unregulated versions available Fully screened Improved blocking performance Fast data settling time Available for operation at 868.3MHz, 869.5MHz and 869.85MHz in Europe, the RX3G combines full screening with internal filtering to ensure EMC compliance by minimising spurious radiation and susceptibility. The module suits one-to-one and multi-node wireless links in applications including car and building security, EPOS and inventory tracking, remote industrial process monitoring and computer networking. Because of the small size and low power requirements, the RX3G is ideal for use in portable, battery-powered wireless applications such as hand-held terminals. Technical Summary Single conversion FM superhet SAW front end filter gives >50dB image rejection Supply: +5V (± 10%) Current consumption: 10mA (typ.) -102dBm sensitivity @ 1ppm BER, 64kbps version -108dBm sensitivity @ 1ppm BER, 15kbps version RSSI output with 50dB range Extremely low LO leakage, -125dBm typical Evaluation platforms: Universal Evaluation Kit, NBEK + SIL carrier Radiometrix Ltd RX3G data sheet page 1 Pin description RF IN (pin 1) 50 input from the antenna, DC isolated. RF GND (pin 2) RF ground pin, internally connected to the module screen and pin 6 (0V). This pin should be connected to the RF return path (coax braid, main PCB ground plane etc.) Fig 2: physical dimensions & pin outs RF GND (pin 3) Not fitted on non-regulator 5V variant En (Regulator version) (pin 4) Rx enable. <0.15V shuts down module (current <1uA). >1.7V enables the receiver. Impedance ~1Mohm. Observe slew rate requirements (see apps notes). Not fitted on non-regulator 5V variant. RSSI (pin 5) Received signal strength indicator with 60dB range. See page 4 for typical characteristics. 0V (pin 6) DC supply ground. Internally connected to pin 2/3 and module screen. Vcc (5V variant) (pin 7) Externally regulated 5V DC supply. Max ripple content 0.1Vp-p. Vcc (for regulator variant) (pin 7) 5.1V to +16V DC supply. Max ripple content 0.1Vp-p. Decoupling is not generally required. AF out (pin 8) Buffered and filtered analogue output from the FM demodulator. Standing DC bias 2V approx. External load should be >10k // <100pF. RXD (pin 9) This digital output from the internal data slicer is a squared version of the signal on pin 8 (AF). It may be used to drive external decoders. The data is true data, i.e. as fed to the transmitter. Radiometrix Ltd RX3G data sheet page 2 Absolute maximum ratings Exceeding the values given below may cause permanent damage to the module. Operating temperature -20C to +70C Storage temperature -40C to +100C Vcc (pin 7) -0.1V to +5.5V RSSI, AF, RXD (pins 5,8,9) -0.1V to +3V RF IN (pin 1) 50V DC, +10dBm RF Performance specifications (Vcc = 5.0V / temperature = 20 C unless stated) pin min. typ. max . units notes 5 5 5 4.5 4.5 9 5.0 5.0 15 5.5 16 18 V V mA 1 RF/ IF RF sensitivity for 10dB (S+N/N) RF sensitivity for 1ppm BER RF sensitivity for 1ppm BER RSSI range IF bandwidth Image rejection IF rejection (10.7MHz) LO leakage, conducted 1,2 1,2 1,2 1,2 1 1 1 50 100 - -113 -108 -102 50 180 54 -125 -110 dBm dBm dBm dB kHz dB dB dBm Baseband Baseband bandwidth @ -3dB Baseband bandwidth @ -3dB AF level DC offset on AF out Distortion on recovered AF Load capacitance, AFout/RXD 8 8 8 8 8 3,8 0 0 200 1.5 - 250 2 1 - 7.8 50 350 2.5 5 100 kHz kHz mVP-P V % pF DYNAMIC TIMING Power up with signal present Power up to valid RSSI Power up to stable data Power up to stable data Power up to stable data 3,5 3,9 3,9 3,9 - 0.5 6 1.5 10 1 ms ms ms ms 1,5 1,9 1,9 1,9 - 100 0.5 5 0.2 1 μs ms 0.5 ms DC supply Supply voltage Supply voltage (regulator ver.) Supply current Signal applied with supply on RSSI response time (rise/fall) Signal to stable data Signal to stable data Signal to stable data Signal to stable data Time between data transitions 15kbps version 64kbps version 15kbps version 64kbps version 2 3 3 3, 15kbps version 3, 64kbps version 3, -DS version 3, 15kbps 3, 15kbps DS 3, 64kbps 3, 64kbps DS 0.0667 1.5 ms 4, 15kbps 0.0667 75 ms 4, 15kbps DS Time between data transitions 9 0.0156 0.2 ms 4, 64kbps 0.0156 3 ms 4, 64kbps DS Mark:space ratio 9 20 50 80 % 5 Notes: 1. Current increases at higher RF input levels (>-20dBm and above). 2. For received signal with ±30kHz FM deviation. 3. Typical figures are for signal at centre frequency, max. figures are for ±50kHz offset. 4. For 50:50 mark to space ratio (i.e. squarewave). 5. Average over 10ms (15kbps version) or 3ms (64kbps version) at maximum data rate. Radiometrix Ltd 9 RX3G data sheet page 3 Power supply requirements The standard RX3G requires a regulated 5V supply with ripple content <100mVpk-pk However, built-in regulator in the regulator version RX3G delivers a constant 5V to the module circuitry when the external supply voltage is 5V or greater, with 40dB or more of supply ripple rejection. This ensures constant performance up to the maximum permitted supply rail (16V max.) and removes the need for external supply decoupling except in cases where the supply rail is extremely poor (ripple/noise content >0.1Vp-p). Note, however, that for supply voltages lower than 5V the regulator is effectively inoperative and supply ripple rejection is considerably reduced. Under these conditions the ripple/noise on the supply rail should be below 10mVp-p to avoid problems. If the quality of the supply is in doubt, it is recommended that a 10F low-ESR tantalum or similar capacitor be added between the module supply pin (Vcc) and ground, together with a 10 series feed resistor between the Vcc pin and the supply rail. Received Signal Strength Indicator (RSSI) The module incorporates a wide range RSSI which measures the strength of an incoming signal over a range of approximately 50dB. This allows assessment of link quality and available margin and is useful when performing range tests. The output on pin 5 of the module has a standing DC bias in the region of 0.5V with no signal, rising to around 1V at maximum indication. The RSSI output source impedance is high (~100k) and external loading should therefore be kept to a minimum. To ensure a fast response the RSSI has limited internal decoupling of 10nF to ground. This may result in a small amount of ripple on the DC output at pin 5 of the module. If this is a problem further decoupling may be added, in the form of a capacitor from pin 5 to ground, at the expense of response speed. Typical RSSI characteristic is as shown below: 1100 1000 RSSI VOLTAGE 900 800 700 600 500 400 300 200 -130 -120 -110 -100 -90 -80 -70 -60 -50 RF input level (dBm) Radiometrix Ltd RX3G data sheet page 4 Module mounting considerations The module may be mounted vertically or bent horizontal to the motherboard. Good RF layout practice should be observed – in particular, any ground return required by the antenna or feed should be connected directly to the RF GND pin at the antenna end of the module, and not to the 0V pin which is intended as a DC ground only. All connecting tracks should be kept as short as possible to avoid any problems with stray RF pickup. If the connection between module and antenna does not form part of the antenna itself, it should be made using 50 microstrip line or coax or a combination of both. It is desirable (but not essential) to fill all unused PCB area around the module with ground plane. The module may be potted if required in a viscous compound which cannot enter the screen can. Warning: DO NOT wash the module. It is not hermetically sealed. Variants and ordering information The RX3G receivers are manufactured in several variants: Data rate: Slower version: Faster version: Frequency: 868.30MHz 869. 50MHz 869.85MHz 914.50MHz 7.8kHz baseband B/W, (suffix -15) 50kHz baseband B/W, (suffix -64) 50kHz baseband B/W, (suffix -128) data rate up to 15kb/s data rate up to 64kb/s data rate up to 128kb/s (suffix –868.30) (suffix -869.50) (suffix –869.85) (suffix –914.50) The following data rate variants are standard: RX3G-869.85-15-5V-DS RX3G-869.85-64-5V-DS 869.85MHz, 15kb/s Data Slicer for Non-bit balanced data 869.85MHz, 64kb/s Data Slicer for Non-bit balanced data RX3G-869.85-15-5V RX3G-869.85-64-5V 869.85MHz, 15kb/s Manchester Encoded data packet with preamble 869.85MHz, 64kb/s Manchester Encoded data packet with preamble RX3G-869.85-128-5V 869.85MHz, 128kb/s Regulator version: RX3G-869.85-15-DS RX3G-869.85-64-DS RX3G-869.85-128 869.85MHz, 15kb/s 869.85MHz, 64kb/s 869.85MHz, 128kb Matching Transmitters: TX3B-869.85-64 869.85MHz For other variants please contact the sales department Evaluation platforms: 1. Universal Evaluation Kit 2. NBEK + SIL carrier Radiometrix Ltd RX3G data sheet page 5 Radiometrix Ltd Hartcran House 231 Kenton Lane Harrow, Middlesex HA3 8RP ENGLAND Tel: +44 (0) 20 8909 9595 Fax: +44 (0) 20 8909 2233 [email protected] www.radiometrix.com Copyright notice This product data sheet is the original work and copyrighted property of Radiometrix Ltd. Reproduction in whole or in part must give clear acknowledgement to the copyright owner. Limitation of liability The information furnished by Radiometrix Ltd is believed to be accurate and reliable. Radiometrix Ltd reserves the right to make changes or improvements in the design, specification or manufacture of its subassembly products without notice. Radiometrix Ltd does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of third parties which may result from the use of its products. This data sheet neither states nor implies warranty of any kind, including fitness for any particular application. These radio devices may be subject to radio interference and may not function as intended if interference is present. We do NOT recommend their use for life critical applications. The Intrastat commodity code for all our wireless modules is: 8542 6000 R&TTE Directive After 7 April 2001 the manufacturer can only place finished product on the market under the provisions of the R&TTE Directive. Equipment within the scope of the R&TTE Directive may demonstrate compliance to the essential requirements specified in Article 3 of the Directive, as appropriate to the particular equipment. Further details are available on The Office of Communications (Ofcom) web site: http://www.ofcom.org.uk/radiocomms/ifi/ Information Requests Ofcom Riverside House 2a Southwark Bridge Road London SE1 9HA Tel: +44 (0)845 456 3000 or 020 7981 3040 Fax: +44 (0)20 7783 4033 [email protected] European Radiocommunications Office (ERO) Peblingehus Nansensgade 19 DK 1366 Copenhagen Tel. +45 33896300 Fax +45 33896330 [email protected] www.ero.dk