EM260 ZigBee/802.15.4 Network Processor - 120-0260 ... - wless.ru

More documents

Recommendations

Info

EM2603.6.2 TransmitTable 8 lists the key parameters of the integrated IEEE 802.15.4 transmitter on the EM260.Note: Transmit Measurements were collected with Ember’s EM260 Ceramic Balun Reference Design at2440MHz and using the EmberZNet software stack Version 3.0.1. The Typical number indicates one standarddeviation below the mean, measured at room temperature (25C). The Min and Max numbers are measuredover process corners at room temperature (25C).Table 8. Transmit CharacteristicsParameter Test Conditions Min. Typ. Max. UnitMaximum output power (boostmode)At highest power setting 4.5 dBmMaximum output power At highest power setting -0.52.5 dBmMinimum output power At lowest power setting - 32 dBmError vector magnitude As defined by IEEE 802.15.4,which sets a 35% maximum15 25 %Carrier frequency error - 40 + 40 ppmLoad impedance 200 ΩPSD mask relative 3.5MHz away - 20 dBPSD mask absolute 3.5MHz away - 30 dBm3.6.3 SynthesizerTable 9 lists the key parameters of the integrated synthesizer on the EM260.Table 9. Synthesizer CharacteristicsParameter Test Conditions Min. Typ. Max. UnitFrequency range 2400 2500 MHzFrequency resolution 11.7 kHzLock time From off, with correct VCO DAC setting 100 μsRelock timeChannel change or RX/TX turnaround(IEEE 802.15.4 defines 192μs turnaroundtime)100 μsPhase noise at 100kHz - 71 dBc/HzPhase noise at 1MHz - 91 dBc/HzPhase noise at 4MHz -103Phase noise at 10MHz -111dBc/HzdBc/Hz120-0260-000J Page 14
EM2604 Functional DescriptionThe EM260 connects to the Host platform through either a standard SPI interface or a standard UARTinterface. The EmberZNet Serial Protocol (EZSP) has been defined to allow an application to be written on ahost platform of choice. Therefore, the EM260 comes with a license to EmberZNet, the Ember ZigBeecompliantsoftware stack. The following brief description of the hardware modules provides the necessarybackground on the operation of the EM260. For more information, contact www.ember.com/support.4.1 Receive (RX) PathThe EM260 RX path spans the analog and digital domains. The RX architecture is based on a low-IF, superheterodynereceiver. It utilizes differential signal paths to minimize noise interference. The input RF signal ismixed down to the IF frequency of 4MHz by I and Q mixers. The output of the mixers is filtered and combinedprior to being sampled by a 12Msps ADC. The RX filtering within the RX path has been designed to optimize theco-existence of the EM260 with other 2.4GHz transceivers, such as the IEEE 802.11g and Bluetooth.4.1.1 RX BasebandThe EM260 RX baseband (within the digital domain) implements a coherent demodulator for optimalperformance. The baseband demodulates the O-QPSK signal at the chip level and synchronizes with the IEEE802.15.4-2003 preamble. An automatic gain control (AGC) module adjusts the analog IF gain continuously(every ¼ symbol) until the preamble is detected. Once the packet preamble is detected, the IF gain is fixedduring the packet reception. The baseband de-spreads the demodulated data into 4-bit symbols. Thesesymbols are buffered and passed to the hardware-based MAC module for filtering.In addition, the RX baseband provides the calibration and control interface to the analog RX modules,including the LNA, RX Baseband Filter, and modulation modules. The EmberZNet software includes calibrationalgorithms which use this interface to reduce the effects of process and temperature variation.4.1.2 RSSI and CCAThe EM260 calculates the RSSI over an 8-symbol period as well as at the end of a received packet. It utilizesthe RX gain settings and the output level of the ADC within its algorithm. The linear range of RSSI is specifiedto be 40dB over all temperatures. At room temperature, the linear range is approximately 60dB (-90 dBm to -30dBm).The EM260 RX baseband provides support for the IEEE 802.15.4-2003 required CCA methods summarized inTable 10. Modes 1, 2, and 3 are defined by the 802.15.4-2003 standard; Mode 0 is a proprietary mode.Table 10. CCA Mode BehaviorCCA ModeMode Behavior0 Clear channel reports busy medium if either carrier sense OR RSSI exceeds their thresholds.1 Clear channel reports busy medium if RSSI exceeds its threshold.2 Clear channel reports busy medium if carrier sense exceeds its threshold.3 Clear channel reports busy medium if both RSSI and carrier sense exceed their thresholds.The EmberZNet Software Stack sets the CCA Mode, and it is not configurable by the Application Layer. Forsoftware versions beginning with EmberZNet 2.5.4, CCA Mode 1 is used, and a busy channel is reported if theRSSI exceeds its threshold. For software versions prior to 2.5.4, the CCA Mode was set to 0.At RX input powers higher than –25dBm, there is some compression in the receive chain where the gain is notproperly adjusted. In the worst case, this has resulted in packet loss of up to 0.1%. This packet loss can bePage 15120-0260-000J
Page 1 and 2: INSPIRE GK12 Lesson PlanLesson Titl
Page 4 and 5: EM2601 Pin AssignmentsVDD_24MHZOSCA
Page 6 and 7: EM260Pin # Signal DirectionDescript
Page 8 and 9: EM260The MAC interfaces the data me
Page 10 and 11: EM2603.3 Environmental Characterist
Page 12 and 13: EM2603.5 Digital I/O Specifications
Page 16 and 17: EM260seen in range testing measurem
Page 18 and 19: EM260operations, consider an EM260
Page 20 and 21: EM260Table 12 lists the specificati
Page 22 and 23: EM2605 SPI ProtocolThe EM260 Low Le
Page 24 and 25: EM2605.2.5 SpacingTo ensure that th
Page 26 and 27: EM260Table 14 lists the timing para
Page 28 and 29: EM260will be 0x82, since the versio
Page 30: EM2605.7.1 SPI Protocol VersionnHOS
Page 34 and 35: EM26022. Stop transmitting after th
Page 36 and 37: EM260The UART signals follow the us
Page 38 and 39: EM2608 Typical ApplicationFigure 14
Page 40 and 41: EM2609 Mechanical DetailsThe EM260
Page 42 and 43: EM26010 QFN40 FootprintFigure 18 de
Page 44 and 45: EM26012 Part MarkingThe EM260 part
Page 46 and 47: EM260Figure 23. Detailed Tape and R
Page 48 and 49: EM260Figure 25. EM260 Tray Informat
Page 50 and 51: EM26015 Abbreviations and AcronymsA
Page 52 and 53: EM26016 References• ZigBee Specif
Page 54: EM260Revision Location Description

EM260 ZigBee/802.15.4 Network Processor - 120-0260 ... - wless.ru

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?