EV9900A CML Microcircuits Evaluation Kit User Manual COMMUNICATION SEMICONDUCTORS UM9900A/3 December 2008 Features • • 1 Complete 400 MHz Transceiver (Initial Configuration for 410 - 430MHz Tx / 410 430MHz Rx) • Test Access for Important Signals • 14.4MHz Reference for 9600bps / 8000bps / 4800bps etc. data rates Configurable for 800 MHz (e.g. 819 825MHz Tx / 864 - 870MHz Rx Transceiver) • Parallel Interface to a µC Brief Description The EV9900A allows evaluation of the CMX990 Baseband and RF Modem IC. The design is a flexible platform to allow users to configure and evaluate the CMX990 for various applications and frequency bands. Initial configuration is for 410-430MHz operation with 25kHz channel spacing and 9600bps. A number of RF circuits, such as VCO’s, PA and LNA, are provided on the EV9900A to facilitate easy evaluation. The PA and LNA are configurable for different operating bands through component value changes (contact CML for further information). Serial numbers 198189 – 198203 are supplied configured for external Auxiliary LO operation – please refer to the “Addendum” at the end of the document for further information. © 2008 CML Microsystems Plc 25 November 2008 Evaluation Kit for CMX990 EV9900A Parallel Control Interface External Reference Input Temp Sensor Uncommitted buffer amplifiers Optional Elements (Default = Unpopulated) VCTCXO Optional paths Temp Sensor Aux VCO Coupler TX OUT TX PA CMX990 TX VCO External LO Inputs TXFB RF ANT PIN Switch Power Detector RX MIX IN Main VCO (Module) Optional Filter / Attenuator Discrete Main VCO Crystal Filter RX IN BPF LNA IF OUT IF IN Figure 1 – Block Diagram © 2007 CML Microsystems Plc 2 UM9900A/3 Evaluation Kit for CMX990 EV9900A CONTENTS Page Section 1 Brief Description ..................................................................................... 1 2. Preliminary Information.......................................................................... 4 2.1 Laboratory Equipment............................................................... 4 2.2 Handling Precautions ................................................................ 4 2.3 Approvals.................................................................................... 4 3. Quick Start ............................................................................................... 5 3.1 Setting-Up ................................................................................... 5 3.2 Adjustments ............................................................................... 6 3.3 Operation .................................................................................... 7 4. Signal Lists .............................................................................................. 9 5. Circuit Schematics and Board Layouts.............................................. 14 6. Detailed Description ............................................................................. 16 6.1 Hardware Description.............................................................. 16 6.2 Adjustments and Controls ...................................................... 18 6.3 Firmware Description .............................................................. 19 6.4 Software Description............................................................... 19 6.5 Application Information........................................................... 19 6.6 Evaluation Tests ...................................................................... 19 6.7 Troubleshooting....................................................................... 22 7. Performance Specification................................................................... 24 7.1 Electrical Performance ............................................................ 24 Addendum .......................................................................................................... 26 It is always recommended that you check for the latest product datasheet version from the Datasheets page of the CML website: [www.cmlmicro.com]. © 2007 CML Microsystems Plc 3 UM9900A/3 Evaluation Kit for CMX990 2. EV9900A Preliminary Information The EV9900A provides a platform for the evaluation of the CMX990. To use the EV9900A, a separate micro-controller or PC, for example, is required to program the CMX990 via its parallel interface. This controlling device is not included on the EV9900A, however a CML product is available to provide the controlling functionality: the EV9902. 2.1 Laboratory Equipment The following laboratory equipment is needed to use this evaluation kit: • • • • Dual Power Supply Spectrum Analyzer RF Attenuator RF Signal Generator For more detailed design or investigation work the other RF test equipment may be required. 2.1.1 Power Supply The supply input voltage to the PCB, for all circuits except the PA, is 7.2V (5.25V to 7.6V acceptable). On board regulators are provided to generate all voltage rails used on the PCB (3V and 5V rails are used). The supply to the PA is directly connected to the PA: a voltage of 3.6V is recommended. The 7.2V supply should be rated at 1A and the 3.6V supply rated at 2A. NOTE: Care should be exercised with the supplies as they are not protected for reverse polarity. For optimum RF performance, the PA supply is connected directly to the RF5110G device so care is required to ensure the RF5110G manufacturer's ratings are not exceeded. 2.2 Handling Precautions Like most evaluation kits, this product is designed for use in office and laboratory environments. The following practices will help ensure its proper operation. 2.2.1 Static Protection This product uses low power CMOS circuits that can be damaged by electrostatic discharge. Partially damaged circuits can function erroneously, leading to misleading results. Observe ESD precautions at all times when handling this product. 2.2.2 Contents - Unpacking Please ensure that you have received all of the items on the separate information sheet (EK9900A) and notify CML within 7 working days if the delivery is incomplete. 2.3 Approvals This product is not approved to any EMC or other regulatory standard. Users are advised to observe local statutory requirements, which may apply to this product and the radio frequency signals that may emanate from it. © 2007 CML Microsystems Plc 4 UM9900A/3 Evaluation Kit for CMX990 3. EV9900A Quick Start This section provides instructions for users who wish to experiment immediately with the evaluation kit. A more complete description of the kit and its use appears later in this document. The EV9900A includes a CMX990 device that is described in its own, separate, datasheet. Accordingly, the user should read the CMX990 datasheet before using the EV9900A. 3.1 Setting-Up The following procedure is recommended: 1. Connect test leads as required, including the host µController to parallel interface J13. 2. The power amplifier output should be connected to a suitable 50Ω load. THE USE OF AN EXTERNAL 50Ω LOAD IS ESSENTIAL TO PREVENT POSSIBLE DAMAGE TO THE PA STAGE. 3. Power should be applied to the main supply (7.2V nominal). 4. The CMX990 device should be reset by issuing a RESET task to the host µController parallel interface (using the TASK bits (b3 - b0) of the Command register [address $01]). 5. Power should be applied to the power amplifier supply connector (3.5V). The board is now ready for operation. An example of typical connections to the EV9900A is shown in Figure 2. 30dB RF Attenuator RF Spectrum Analyzer J9 J8 J1 J10 J18 +7.2V Power Amplifier +3.5V Ground J6 J7 CMX 990 J12 J11 J2 J4 J13 J5 RF Signal Generator Figure 2 – Typical Connections for EV9900A © 2007 CML Microsystems Plc 5 UM9900A/3 Evaluation Kit for CMX990 EV9900A Figure 3 EV9900A top and bottom views 3.2 Adjustments None. © 2007 CML Microsystems Plc 6 UM9900A/3 Evaluation Kit for CMX990 3.3 EV9900A Operation The CMX990 is a complex RF and Baseband Modem IC. It is recommended that the user familiarise themselves with the datasheet of this device prior to attempting to use the EV9900A. To use the EV9900A the user will need a mechanism to send and receive data and commands via the 8-bit parallel host µController interface on the CMX990, which is brought out on connector J13 on the EV9900A. The CMX990 datasheet gives details of the registers and commands. To operate the CMX990, some typical command sequences are given below: Data Rate The default data rate with a 14.4MHz reference is 6000bps. Data rates can be configured using the clock control register in the CMX990 (C-BUS address $29). The following example C code shows a typical configuration for common data rates: register_write(CLOCK_CONTROL, 0x45); //9600 bps e.g. 25kHz channel register_write(CLOCK_CONTROL, 0x85); //4800 bps e.g. 12.5kHz channel register_write(CLOCK_CONTROL, 0x46); //8000 bps e.g. 12.5kHz channel Receive Mode The following example C code shows a typical configuration for reception. register_write(POWER_UP_2, 0x08); register_write(POWER_UP_2, 0x01); register_write(POWER_UP_1, 0xEE); register_write(POWER_UP_2, 0xF1); register_write(AUX_DAC_1_MSB,169); //Reset //Vbias on //Clock+BB+Vreg,+Rx:on & Opamps+Tx:off //DACs on //AFC to mid rail (1.65V) //Set up synths: set_main_synth(0x8480,0x807530); //750MHz, low side, Rx Freq=420.1MHz //(assuming ref 14.4MHz & comp 12.5kHz) set_aux_synth(0x8090,0x870C); //180.4MHz (for 45.1MHz IF) //(assuming ref 14.4MHz & comp100kHz) register_write(CONTROL, 0xE9); //AGC max gain & run, IQ offset fine, //AFC Slow, PLL Narrow register_write(MODE, 0xD2); //IRQ enabled, scrambler enabled, //INV bit enabled, Main ADC enabled, Rx mode register_write(POWER_UP_2,0xF5); //Turn LNA on. register_write(COMMAND, 0x60); //Acquire DC offset & AFC //DelayBy(90000); //Wait for Offset to complete Following the above routines the user may initiate reception of data using the modem task commands in Command register ($01). © 2007 CML Microsystems Plc 7 UM9900A/3 Evaluation Kit for CMX990 EV9900A Transmit Mode The following example ‘C’ code shows a configuration for the CMX990 transmitter. register_write(POWER_UP_2, 0x08); register_write(POWER_UP_2, 0x01); register_write(POWER_UP_1, 0xE0); //Reset //Vbias on //Clock, BB, Vreg:on & Opamps+Tx+Rx:off register_write(COMMAND, RESET); //give modem reset command register_write(CONTROL, 0x00); register_write(MODE, 0xB1); // //IRQ, Tx Mode, Scrambler & Main DAC enabled The user should also ensure that the synthesisers are set to appropriate frequencies and enabled. The transmitter is now ready to start transmission but the offset loop is unlikely to lock without modulation being generated. To achieve lock, write task TSO (Transmit Scrambler Output), which will result in a continuous sequence of random data being generated by the baseband modem. The transmitter is enabled by setting the TxIFRF bit in POWER_UP_1 register. register_write(COMMAND, TSO); register_write(POWER_UP_1,0xE1); //Transmit Scrambler Output //Clock, BB, Vreg, Opamps off , Tx RFIF on The above sequence just enables the transmitter. The power amplifier can now be enabled using the DAC0 Output. This DAC has an automatic ramping circuit to allow an accurate power ramping profile to be applied to the power amplifier. register_write(AUX_DAC_0_MSB,0x39); //Turn PA on at minimum power to all lock For some operating frequencies the free-running frequency of the Tx VCO needs to be within certain limits of the desired Tx frequency (as described in the datasheet). On the EV9900A this can be achieved using the pre-charge facility as follows: Register_write(0x24,0x11); Delay(1000); Register_write(0x24,0x01); //Enable Tx VCO Charge //Wait while VCO tunes //Disable Tx VCO Charge The power amplifier may now be either ramped up or, for basic testing, enabled to the required power. An output power of ~1W is generally achieved with a DAC0 value of 0xb0. register_write(AUX_DAC_0_MSB,0xb0); © 2007 CML Microsystems Plc 8 //PA output approx 1W UM9900A/3 Evaluation Kit for CMX990 4. EV9900A Signal Lists CONNECTOR PINOUT Connector Ref. Connector Pin No. Signal Name Signal Type J1 N/A REFIN RF / Clock J2 J3 N/A N/A RXIN1 RXIN2 RF RF J4 J5 N/A N/A IFOUT IF IN RF RF J6 J7 J8 J9 J10 J11 N/A N/A N/A N/A N/A N/A TXI TXQ TX VCO O/P TXOUT MAIN LO AUX LO BASEBAND BASEBAND RF RF RF RF J12 J12 J12 J13 3 2 1 1 – 40 +7.2V +3.5V GND HOST DC DC DC LOGIC INTERFACE J14 J15 J15 J15 J15 J15 J16 J17 1–8 1,3,5,7 2 4 6 8 VOID N/A TX/RX/I/Q TX/RX/I/Q DAC3 DAC2 ADC5 ADC4 VOID N/A BASEBAND BASEBAND BASEBAND BASEBAND BASEBAND BASEBAND N/A N/A J18 N/A RF_ANT RF Description Clock input / output. By selecting coupling capacitors (C3 / C4) this port may be used to monitor the on-board 14.4MHz reference or the external reference input. Input to receiver LNA. By selecting components this port may be used as an LNA output or input to the receiver mixer. NB: This port is a test port (solder pads) designed to allow connection of a coax cable. 1st Mixer Output or input to IF filter (F2). Output of IF filter (F2) or input to CMX990 receiver IF stages. EV9900A is not configured to use this port. EV9900A is not configured to use this port. Monitor point for Tx VCO feedback signal. 400MHz / 800MHz transmitter output. Input or output / monitor for main local oscillator. Input or output / monitor for auxiliary (180MHz) local oscillator (normally not connected). 7.2V power supply input. 3.5V power supply for RF power amplifier. Power supply ground. 8 bit parallel interface from CMX990 to host / controller or PC. See schematics and CMX990 datasheet for details. EV9900A is not configured to use this port. EV9900A is not configured to use these pins. DAC3 output. DAC2 output. ADC5 input. ADC4 input. Void EV9900A is not configured to use this connector. TX / RX Switch Output (Default configuration of EV9900A does not use this connector). Table 1 – Signal List © 2007 CML Microsystems Plc 9 UM9900A/3 Evaluation Kit for CMX990 EV9900A CONNECTOR PINOUT for J13 Connector Signal Signal Pin No. Name Type 1 2 3 4 5 6 7 8 9 10 11 12 13 14 GNDD GNDD ADDRESS5 ADDRESS4 ADDRESS3 ADDRESS2 ADDRESS1 ADDRESS0 GNDD GNDD READN WRITE CSN IRQN POWER POWER I/P I/P I/P I/P I/P I/P POWER POWER I/P I/P I/P O/P 15 16 17 18 19 20 21 22 23 24 25 26 27 GNDD GNDD DATA7 DATA6 DATA5 DATA4 DATA3 DATA2 DATA1 DATA0 GNDD GNDD TX_ON POWER POWER BI BI BI BI BI BI BI BI POWER POWER I/P 28 29, 30 31, 32 33, 34 35, 36 37, 38 39, 40 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Description Connection to digital ground. Connection to digital ground. CMX990 Address (A5). CMX990 Address (A4). CMX990 Address (A3). CMX990 Address (A2). CMX990 Address (A1). CMX990 Address (A0). Connection to digital ground. Connection to digital ground. CMX990 read strobe. CMX990 write strobe. CMX990 chip select input. CMX990 open-drain Interrupt output. 10k pull-up resistor to 3.3V (R193) fitted on PCB. Connection to digital ground. Connection to digital ground. CMX990 Data (D7). CMX990 Data (D6). CMX990 Data (D5). CMX990 Data (D4). CMX990 Data (D3). CMX990 Data (D2). CMX990 Data (D1). CMX990 Data (D0). Connection to digital ground. Connection to digital ground. TX Enable for PIN switch, high = TX, low = RX (default configuration does not use this signal). Spare pin. Leave unconnected. Spare pin. Leave unconnected. Spare pin. Leave unconnected. Spare pin. Leave unconnected. Spare pin. Leave unconnected. Spare pin. Leave unconnected. Spare pin. Leave unconnected. Table 2 – Host µController Interface © 2007 CML Microsystems Plc 10 UM9900A/3 Evaluation Kit for CMX990 EV9900A TEST LOOPS Test Loop Ref. Default Measurement Description TL1 LNAON control line from CMX990 TL2 EV9900A is not configured to use this port TL3 EV9900A is not configured to use this port TL4 EV9900A is not configured to use this port TL5 EV9900A is not configured to use this port TL6 EV9900A is not configured to use this port TL7 Control port chip select line (This pin is useful to trigger measurements on command inputs to the CMX990 registers) TL8 DAC 0 (PA Ramping) TL9 DAC 1 (AFC) TL10 Void TL11 Void TL12 Void TL13 Void TL14 Test point for differential amplifier 2 output TL15 Test point for differential amplifier 2 inverting input TL16 2.5V TL17 +2.5V power supply Power amplifier control voltage Table 3 – Test Loops © 2007 CML Microsystems Plc 11 UM9900A/3 Evaluation Kit for CMX990 EV9900A TEST POINTS Test Point Ref. Default Measurement Description TP1 EV9900A is not configured to use this signal TP2 EV9900A is not configured to use this signal TP3 EV9900A is not configured to use this signal TP4 EV9900A is not configured to use this signal TP5 EV9900A is not configured to use this signal TP6 EV9900A is not configured to use this signal TP7 EV9900A is not configured to use this signal TP8 EV9900A is not configured to use this signal TP9 Transmitter PLL VCO control line TP10 EV9900A is not configured to use this signal TP11 Main PLL VCO control line TP12 Auxiliary PLL VCO control line TP13 2.5V 2.5V regulator output TP14 5.0V 5.0V regulator output for digital baseband TP15 0V Analogue ground TP16 0V Analogue ground TP17 0V Digital ground TP18 0V Digital ground TP19 5.0V 5.0V regulator output for analogue baseband TP20 3.3V 3.3V regulator output TP21 3.3V 3.3V regulator output for VCO TP22 EV9900A is not configured to use this signal TP23 PA output power detector voltage TP24 PA Temperature sensor voltage TP25 AFC Temperature sensor voltage TP26 5.0V 5.0V regulator output for VCO Table 4 – Test Points © 2007 CML Microsystems Plc 12 UM9900A/3 Evaluation Kit for CMX990 EV9900A JUMPERS Link Ref. Positions Default Position Description J14 Open EV9900A is not configured to use this port J15 Open EV9900A is not configured to use this port Table 5 – Jumpers Notes: I/P O/P BI TL TP = = = = = © 2007 CML Microsystems Plc Input Output Bidirectional Test Loop Test Point 13 UM9900A/3 Evaluation Kit for CMX990 5. EV9900A Circuit Schematics and Board Layouts For clarity, circuit schematics are available as separate high-resolution files. The layout on each side is shown in Figure 4, below: Figure 4a - PCB Layout: top © 2007 CML Microsystems Plc 14 UM9900A/3 Evaluation Kit for CMX990 EV9900A Figure 4b – PCB Layout: bottom © 2007 CML Microsystems Plc 15 UM9900A/3 Evaluation Kit for CMX990 6. EV9900A Detailed Description The CMX990 datasheet (not included but available at www.cmlmicro.com) should be referred to for a detailed description of the CMX990 device. The EV9900A functionality includes: • • • • Demonstration of the CMX990 RF functionality at ≈400MHz (or ≈800MHz by component changes. Please contact CML for further information.) Demonstration of EN 300 113 receive performance. Interfaces that allow the card to be connected to a host µController, to allow real-time control, or to a PC (a separate interface may be required) An interface allowing the connection of an external reference clock In summary, the EV9900A allows the user to create experiments to investigate all aspects of the CMX990 device. The EV9900A is designed to allow user modification, to support detailed investigation of each user’s specific and different applications. 6.1 Hardware Description Front End LNA The PCB includes a 400MHz discrete bipolar LNA using TR5, which is designed for 410-430MHz and to meet EN 300 113 requirements. The LNA includes some front-end band-pass filtering (L26, L27, C186, C187, C188, C189, C192, C193 and C194). This can be re-configured for operation on other bands with value changes. A 1.8dB Pi attenuator (R162, R173, R174) follows the LNA output. SAW Image Filter By fitting or not fitting certain components the user is able to select either a SAW filter (FL1) or additional T attenuation (R206, R207, R139) to simulate the typical system loss of such a filter. As built, the SAW filter is not fitted, with the attenuator values fitted to give around 3dB loss. Mixer Input The signal from the LNA and filter is then applied to the differential input of the CMX990 RX mixer via a balun transformer T3. The input is matched for the particular band of interest (L5, L33, L28). IF Filter The IF filter (F1A, F1B) is a 45.1MHz 4-pole crystal filter. The pass-band of the filter fitted to the EV9900A is approximately +/-7.5kHz, designed for 25kHz channel spacing, however other filters are available in the same package outline, offering different bandwidths (e.g. +/-3.75kHz for 12.5kHz channel spacing). Correct matching of the filter is necessary to achieving optimum performance. Reference Oscillator A 14.4MHz VCTCXO is provided on the PCB (U1). If U1 is disabled (lifting R1), C4 is removed, and C3 fitted, an alternative clock source can be applied to J1. © 2007 CML Microsystems Plc 16 UM9900A/3 Evaluation Kit for CMX990 EV9900A Transmitter The transmitter provides at least +30dBm in the default configuration (410-430MHz). The 420MHz PA is tuneable (by component changes) over the range 150 to 900MHz, however lower output power is available over 750MHz. The transmit VCO (U8) also has very broad tuning range typically from below 400MHz to above 450MHz with a 3.3V charge pump. U8 would need to be changed for operation on other bands, for example 800MHz (contact CML for further information). The CMX990 RAM DAC output (DAC 0) is connected to the PA control line via a diode and transistor (D10 and TR4) to provide sufficient current to the PA control pin. Local Oscillators VCO’s are provided for the main and aux synthesizers. The aim is to cover the frequency bands of 410-430MHz (Rx and Tx). This requires the following local oscillator frequencies, based on the following frequency plan: Rx Band / MHz 410-430 Tx Band / MHz Tx IF / MHz 410-430 45 Rx IF / MHz 45.1 LO Range / MHz 729.8-769.8 730-770 Table 6 – Local Oscillator Frequencies The VCOs are packaged parts from Z-Communications, who provide a range of VCO’s in the same package outline, so that the user can evaluate other frequency bands if required. These VCOs have some performance limitations and are marginal for EN 300 113 adjacent channel requirements for transmitter and receiver. The facility to use a discrete, high performance, low phase noise VCO circuit, is also provided (TR11, TR12 and coaxial resonator TL6), However this is not enabled in the default configuration. This may be re-tuned by component changes if required by the user. The aux VCO is a discrete design operating at around 180MHz. Again this may be re-tuned by component changes if required by the user. © 2007 CML Microsystems Plc 17 UM9900A/3 Evaluation Kit for CMX990 EV9900A Differential Amplifiers Simple circuits are provided to allow evaluation of the differential amps on the CMX990 (R117, R118, R119, R120, R121, R122, R123, R124, C156 and C157). Temperature Sensors Two temperature sensors are provided, one (U21) adjacent to the PAs and the other (U19) adjacent to the VCTCXO. These are connected to the CMX990 Aux ADC inputs 0 and 1 respectively. Tx/Rx Switch Although not configured in the default EV9900A build, circuits are provided to implement a Tx / Rx switch using PIN diodes. (See section 6.2.1) Interface The EV9900A provides access to the CMX990 parallel interface via connector J13. The EV9900A has test pins to allow measurement of aux DAC outputs and test pins that allow the user to apply test signals to the aux ADC inputs. All RF connectors are SMA type. The power connector provides two separate power connections: one for the power amplifier and the other to supply all other circuits. 6.2 Adjustments and Controls The user has the ability to configure the EV9900A for a number of different operational scenarios. 6.2.1 Tx/Rx Switch The following modifications need to be implemented on the EV9900A (PCB546F) evaluation board to enable a classical series-shunt RX/TX switch. Ref Des R194 C172 C94 L21 C212 L16 C213 C226 410-430MHz value 100R 1n0 1n0 100nH 1008CS 1n0 15nH 0603CS 6p8 6p8 The receiver path components (L16, C213, C226) form a lumped quarter wave section and will need to vary dependent upon the users’ operating band. L21 would also require a value change. The switch will give less than 1dB insertion loss. The main consequence with this topology is that only one control line is required and the logic is as follows; TX_ON = 3V (HIGH) => TX mode, TX_ON = 0V (LOW) => RX mode. This signal is buffered by TR13 and TR14 due to the current required for low transmit through loss. © 2007 CML Microsystems Plc 18 UM9900A/3 Evaluation Kit for CMX990 6.2.2 EV9900A External Local Oscillator To evaluate the performance of the CMX990 it is recommended that a low noise external oscillator be used for the main LO. This is particularly important when performing blocking and adjacent channel tests. An external main LO can be supplied via J10. The following changes are recommended: • • 6.2.3 Remove R78, R81, R164 and R200 (supplies to on-board VCO’s). Ensure C98 (1nF) and R149 (18Ω) are fitted. Intermediate Signal Connections The EV9900A allows a user to connect signals at various points in the signal path of the IC. Details can be found on the schematic and in the list of connectors. Users can choose appropriate matching and configurations to suit their requirements. Note that just connecting test equipment to the ports may not give the expected results – correct RF matching arrangements are required. 6.3 Firmware Description The EV9900A has no embedded firmware. 6.4 Software Description CML products DE9901 and EV9902 (not included) can be used with the EV9900A and include related software. 6.5 Application Information 6.5.1 TX Loop Operating Power Levels The range of input powers to the feedback port (TxFB) of the offset loop is designed to allow operation over an 65dB range (approximately +8 to –57dBm). This is to permit the loop to lock prior to commencing power ramping. 6.6 Evaluation Tests The EV9900A is intended to allow evaluation of CMX990 RF and baseband performance. The following is a list of typical tests from radio modem standards (e.g. EN300113). Some guidance notes on likely EV9900A performance at 410-430MHz are provided. Frequency Error Compliant, based on a selected 14.4MHz VCTCXO. © 2007 CML Microsystems Plc 19 UM9900A/3 Evaluation Kit for CMX990 EV9900A Adjacent Channel Power (ACP) 60dB adjacent channel power can be demonstrated for 12.5kHz channels with G(M)FSK, Bt = 0.27 and 8kbit/s. To achieve this an external LO is required and a TxIF of 45MHz selected. 70dB adjacent channel power can be demonstrated for 25kHz channels with GMSK, Bt = 0.5 and 9.6kbit/s. Compliance with FCC 47CFR90.210 emission mask D can also be demonstrated using the onboard Main VCO module, as shown in the following plot. A 45MHz TXIF was used. This is a 12.5kHz channel mask and requires a change in baud rate to 8kbit/s (register $29, 46h) and BT to 0.3. Marker 1 [T1] RBW 100 Hz 21.30 dBm VBW 1 kHz Mixer 420.10000000 MHz SWT 25 s Unit Ref Lvl 30.3 dBm RF Att 10 dB -20 dBm dB 0 30.5 dB Offset 1 [T1] 1 21.30 dBm A 420.10000000 MHz LN -10 -20 -30 1MAX 1SA -40 -50 -60 -70 FCC210D -80 -90 -100 Center 420.1 MHz Date: 25.OCT.2007 5 kHz/ Span 50 kHz 15:45:05 Figure 5 – FCC 47CFR90.210 emission mask D Spurious Emissions EV9900A is not designed to be compliant with spurious emissions limits as transmitter filtering is not included. Maximum Usable Sensitivity Typically –117dBm for 1% BER (9.6kbit/s, Bt = 0.5). Co-channel Rejection With an interferer on the same frequency this is typically 7dB for 25kHz channel spacing operation (9.6kbit/s). © 2007 CML Microsystems Plc 20 UM9900A/3 Evaluation Kit for CMX990 EV9900A Adjacent Channel Rejection (ACR) ACR performance is limited by local oscillator phase-noise. Typically, 72dB ACR can be demonstrated for 25kHz channels with GMSK, Bt = 0.5 and 9.6kbit/s using the on-board VCO. Enhanced performance can be achieved using an external, low noise, main LO. Intermodulation Typically greater than >65dB tested as EN 300 113. Spurious Response Rejection A front-end SAW filter is not provided on the default configuration EV9900A so spurious response rejection is not guaranteed. However the option to fit a filter to reject such responses (type selected by user) is available. The resulting performance will depend upon the operating band used and the particular rejection characteristics of the chosen filter. Blocking or Desensitisation Blocking performance is approx. 86dB. © 2007 CML Microsystems Plc 21 UM9900A/3 Evaluation Kit for CMX990 6.7 EV9900A Troubleshooting The CMX990 is a complex RF and Baseband system. If incorrectly programmed or modified, results will be at variance from datasheet performance. Please study the datasheet, this manual and the associated schematics and layout drawings carefully when troubleshooting. This section provides some suggestions to help users resolve application issues they might encounter. 6.7.1 Receiver Operation Error Observed Possible Cause No packets are received, however synthesisers are locked and the receiver otherwise appears to be operating correctly. Receiver sensitivity is 30dB less than anticipated. Degraded receiver performance. Degraded receiver sensitivity and/or imbalance in adjacent channel power in the transmitter (i.e. ACP high is much better than ACP low or vice versa) ‘INV’ bit incorrectly set. Invert current setting of ‘INV’ bit. Incorrect baud rate set. Select correct register value. ‘Sign’ bit is incorrectly set. Invert current setting on ‘Sign’ bit Ensure DC offset correction sequence has been executed. To check if a frequency error exists measure the frequency of the main local oscillator either using the measuring equipment in question or compare results from EV9900A with those from the measurement equipment. Incorrect DC offset correction. There is a frequency offset between EV9900A reference oscillator and the test equipment. (Note: EV9900A requires an approximate AFC value to be programmed into the DAC1. A value of 0x95 in register 0x0B is a good starting point.) Poor sensitivity channels on some Remedy The main Tx VCO is not powered down and can drift into the Rx band. or clock control To overcome a frequency error either: a) Use a external reference for the EV9900A b) Tune to control voltage on the AFC output (DAC1). In a normal modem design the Tx VCO (U18) would be powered down during Rx mode. This is not implemented on EV9900A. BER results variable. To overcome the problem the Tx VCO should be disabled during Rx BER testing. This can be done by removing R67. © 2007 CML Microsystems Plc 22 UM9900A/3 Evaluation Kit for CMX990 6.7.2 EV9900A Transmitter Operation Error Observed Transmitter loop does not lock Possible Cause No modulation is present. Transmitter loop does not lock The PA is not turned on. Poor modulation spectrum in transmit. An incorrect filter has been chosen for the selected Tx IF. © 2007 CML Microsystems Plc 23 Remedy Ensure the transmitter is outputting data. The TSO command can be used to continuously send data for testing. Note also the modem needs to be in transmit mode and main DAC enable (register $03) Check the feedback coupling level to the CMX990. Ensure the correct coupler for the band of interest is selected. Select the correct filter using bits 5 and 6 of the Aux PLL M div MSB register ($26). UM9900A/3 Evaluation Kit for CMX990 7. Performance Specification 7.1 Electrical Performance EV9900A 7.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the Evaluation Kit. Min. 0.0 0.0 0 -20 Supply Voltage (VIN - VSS) Supply Voltage (VPA - VSS) Current into or out of VIN VPA and VSS pins Current into or out of any other connector pin Max. 7.6 4.0 +2.0 +20 Units V V A mA Max. 7.6 3.6 24 Units V V MHz 7.1.2 Operating Limits Correct operation of the Evaluation Kit outside these limits is not implied. Notes Supply Voltage (VIN - VSS) Supply Voltage (VPA - VSS) Xtal/External Clock Frequency © 2007 CML Microsystems Plc 24 Min. 5.25 3.0 UM9900A/3 Evaluation Kit for CMX990 7.1.3 EV9900A Operating Characteristics For the following conditions unless otherwise specified: Evaluation Device Xtal Frequency = 14.4MHz, Bit Rate = 9.6k bits/sec, VIN - VSS = 7.2V, VPA - VSS = 3.6V, Tamb = +25°C. Notes DC Parameters (Excluding PA Supply) IDD (CMX990 powersaved) IDD (Tx) IDD (Rx CMX990 internal mixer; LNA enabled) Min. 1 1 1 AC Parameters Tx Output Tx output impedance TX output power Rx Input Rx input impedance Rx Sensitivity Maximum Input Level without damage 2 Typ. Max. 135 200 260 mA mA mA 50 30 Ω dBm 50 -112 Ω dBm dBm 0 Xtal/Clock Input Reference Clock Frequency Reference Clock Level 14.4 3 Units 1 MHz Vp-p µC Interface See CMX990 Datasheet Notes: 7.1.3 1. PCB current consumption, not current consumption of the CMX990. 2. 1% BER 3. Typically clipped sine wave Operating Characteristics - Timing Diagrams Please refer to CMX990 Datasheet for details. © 2007 CML Microsystems Plc 25 UM9900A/3 Evaluation Kit for CMX990 EV9900A Addendum EV9900A PCB serial numbers 198189 to 189203 are supplied configured as follows: R82 (680R), R85 (470R) and R89 (0R) have been removed to disable the on-board Auxiliary VCO, R92 has been fitted (0R) to allow an external Auxiliary LO to be applied via J11. This is due to a problem with the PCB construction that has caused unreliable operation of the Auxiliary VCO when in transmit using a 90MHz IF. The problem can be avoided by using an external source for the AUX LO. EV9900A PCB’s with other serial numbers are unaffected. This does not affect the user's ability to evaluate the CMX990 IC. The user should apply 180.4MHz at –3dBm for receive and 180MHz at –3dBm for transmit operation to J11. © 2007 CML Microsystems Plc 26 UM9900A/3 Evaluation Kit for CMX990 EV9900A Handling precautions: This product includes input protection, however, precautions should be taken to prevent device damage from electro-static discharge. CML does not assume any responsibility for the use of any circuitry described. No IPR or circuit patent licences are implied. CML reserves the right at any time without notice to change the said circuitry and this product specification. CML has a policy of testing every product shipped using calibrated test equipment to ensure compliance with this product specification. Specific testing of all circuit parameters is not necessarily performed.