BIM-418-40 Radiometrix, BIM-418-40 Datasheet
BIM-418-40
Related parts for BIM-418-40
BIM-418-40 Summary of contents
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... Features Miniature PCB Mounting module Licence Exempt operation 418MHz, MPT 1340 (BiM-418-40) ETS 300-220 tested for European use on 433.92 MHz (BiM-433-40) SAW controlled FM transmission at -6dBm ERP. Double conversion Superhet receiver -107dBm receive sensitivity Single 4.5 to 5.5V supply < ...
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... Radiometrix Ltd, BiM Data Sheet page 2 ...
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... Note: unlike the RXD output which is always true data, this output is true data on the BiM-418 and inverted on the BiM-433. Should be driven directly by a CMOS logic device running on the same supply voltage as the module. Analogue drive may be used but must not drive this input above Vcc or below 0V. This input should be held at < ...
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... Don't be tempted to adjust the trimmer on the module, it controls the receive frequency and can only be correctly set-up with an accurate RF signal generator. Radiometrix Ltd, BiM Data Sheet Active low transmit / receive selects with 10kΩ internal pull-ups. They may be driven by open collector or CMOS logic function power down (< ...
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... Initial frequency accuracy Overall frequency accuracy Spurious radiation FM deviation (+/-) Distortion Modulation response @ -3dB RF Parameters - Receive Receive frequency (Frf) BiM-418-40 Receive frequency (Frf) BiM-433-40 Receiver sensitivity AF bandwidth @ -3dB AF output level, pin 13 Local Oscillator leakage, pin 2 IF Bandwidth AFC lock range (5 µ V signal) ...
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... Sinewave centred on +2.5V at pin 14 (TXD) 4. Digital drive, 50:50 mark:space (over 4ms) data pattern. 5. High or Low pulse. 6. Averaged over any 4ms period Absolute maximum ratings Supply voltage Vcc, pin 17 All input / output pins Operating temperature Storage temperature Radiometrix Ltd, BiM Data Sheet Min Typ. 0 ...
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... Antenna requirements Three types of integral antenna are recommended and approved for use with the BiM transceiver : A) Helical: Wire coil, connected directly to pin 2, open circuit at other end. This antenna is very efficient given it's small size (20mm x 4mm dia.). The helical is a high Q antenna, trim the wire length or expand the coil for optimum results ...
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... PCB tracks/earth plane. The space around the antenna is as important as the antenna itself. Radiometrix Ltd, BiM Data Sheet 0 enam eled copp er w ire close w oun diam eter form er ...
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... Type Approval The BiM-418-40 is type approved in the UK to MPT1340 for use in Telemetry, Telecommand and In- Building alarm applications. www.DataSheet4U.com CONFORMANCE to MPT1340 REQUIRES THAT: 1. The transmitting antenna must be one of the 3 variants given in the data sheet. Antenna structures which yield ERP gain are not permitted. ...
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... IC's (see test circuit for linear biasing of TXD input). figure 7: typical microcontroller interface Direct Digital, TXD > RXD at 5V CMOS Levels The data path through a pair of BiM coupled. This places 3 basic constraints that any serial code must satisfy for reliable transfer. 1. Pulse width time ...
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... The data must be "packetised" with no gaps between bytes. i.e. : The data must be preceded by >3ms of preamble (55h or AAh hex) to allow the data slicer in the BiM to settle, followed FFh bytes to allow the receive UART to lock, followed by a unique start of message byte, (01h), then the data bytes and finally terminated by a CRC or check sum ...
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... Thus the decoder may determine the integrity of each even byte received and on a parity failure select the subsequent inverted odd byte. The greater the stagger the higher the immunity to isolated burst errors. Radiometrix Ltd, BiM Data Sheet ...
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... Digitised analogue data Linear operation of BiM transceivers will allow direct transfer of analogue data, however in many applications the distortion and low frequency roll off are too high (e.g. bio-medical data such as ECG). The use of delta modulation is an excellent solution for analogue data in the range 1Hz up to 4KHz with less than 1% distortion ...
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... BiM's may be used in many different configurations from simple pair's to multi-node random access networks. The BiM is a single frequency device thus in a multi node system the signalling protocol must use Time Division Multiple Access TDMA network only one transmitter may time, " ...
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... Interface logic The logic control / data lines in and out of the BiM all have 10kΩ series EMC isolation resistors internal to the BiM (see BiM block diagram). We recommend that RXD and CD outputs be used only to drive CMOS logic inputs and no more than PCB track. Care should also be taken in the routing of the RXD , TXD , CD & ...
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... Provide LED status lights on TX, RX & CD (direct or by plug on test PCB) • For complex networks - provide software test routines for :-continuous RX, continuous TX, loop test, Simple master / slave "ping-pong". • The BiM-can (fig. 11) is available and may be used for shielding to achieve an optimal radio performance figure 11: BiM-can layout figure 12: hole pattern BiM-UHF + BiM-can All Radiometrix’ ...
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... 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 ...