Texas Instruments 3138 155 232931 - Manuals

CC2420 SWRS041B Page 7 of 89 3 Features • 2400 – 2483.5 MHz RF Transceiver • Direct Sequence Spread Spectrum (DSSS) transceiver • 250 kbps data rate, 2 MChip/s chip rate • O-QPSK with half sine pulse shaping modulation • Very low current consumption (RX: 18.8 mA, TX: 17.4 mA) • High sensitivity (-95...

CC2420 SWRS041B Page 9 of 89 6 Electrical Specifications Measured on CC2420 EM with transmission line balun, T A = 25 ° C, DVDD3.3 and VREG_IN = 3.3 V, internal voltage regulator used if nothing else stated. 6.1 Overall Parameter Min. Typ. Max. Unit Condition / Note RF Frequency Range 2400 2483.5 MH...

CC2420 SWRS041B Page 15 of 89 7 Pin Assignment VR E G _ O U T A V DD_ CHP QLP48 7x7 1 2 3 4 5 6 7 8 9 10 11 12 35 34 33 32 31 30 29 28 27 26 25 36 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 CC2420 R_BIAS A V DD_ IF1 VR E G _ IN VR E G _ E N X O SC 16_Q1 X O SC 16_Q2 A T ...

CC2420 SWRS041B Page 17 of 89 8 Circuit Description Se rial mi c roc on tr ol le r in te rfa c e LNA DIGITAL DEMODULATOR - Digital RSSI- Gain Control- Image Suppression- Channel Filtering- Demodulation- Frame synchronization DIGITAL MODULATOR - Data spreading- Modulation On-chip BIAS DIGITAL INTERFA...

CC2420 SWRS041B Page 18 of 89 and Q LO signals to the down-conversion mixers in receive mode and up-conversion mixers in transmit mode. The VCO operates in the frequency range 4800 – 4966 MHz, and the frequency is divided by two when split in I and Q. A crystal must be connected to XOSC16_Q1 and XOS...

CC2420 SWRS041B Page 19 of 89 9 Application Circuit Few external components are required for the operation of CC2420 . A typical application circuit is shown in Figure 4. The external components shown are described in Table 1 and typical values are given in Table 2. Note that most decoupling capacit...

CC2420 SWRS041B Page 20 of 89 Ref Description C42 Voltage regulator load capacitance C61 Balun and match C62 DC block to antenna and match C71 Front-end bias decoupling and match C81 Balun and match C381 16MHz crystal load capacitor, see page 53 C391 16MHz crystal load capacitor, see page 53 L61 DC ...

CC2420 SWRS041B Page 21 of 89 35 34 33 32 31 30 29 28 27 26 25 36 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 1 2 3 4 5 6 7 8 9 10 11 12 QLP48 7x7 CC2420 RF Transceiver DSUB_ CORE DSUB_ PADS AVDD _ADC DVDD _ADC DG UARD AVDD _IF2 D GND_G UARD AVDD _RF2 D GND NC NC RES ETn ...

CC2420 SWRS041B Page 23 of 89 Item Single ended output, transmission line balun Single ended output, discrete balun Differential antenna C42 10 µF, 0.5 Ω < ESR < 5 Ω 10 µF, 0.5 Ω < ESR < 5 Ω 10 µF, 0.5 Ω < ESR < 5 Ω C61 Not used 0.5 pF, +/- 0.25pF, NP0, 0402 Not used C62 Not used 5...

CC2420 SWRS041B Page 24 of 89 10 IEEE 802.15.4 Modulation Format This section is meant as an introduction to the 2.4 GHz direct sequence spread spectrum (DSSS) RF modulation format defined in IEEE 802.15.4. For a complete description, please refer to [1]. The modulation and spreading functions are i...

CC2420 SWRS041B Page 25 of 89 1 0 1 0 1 1 0 1 I-phase Q-phase 1 0 0 1 1 0 0 1 0 0 0 1 1 0 0 1 0 1 1 0 0 1 0 1 T C 2T C Figure 7. I / Q Phases when transmitting a zero-symbol chip sequence, T C = 0.5 µs 11 Configuration Overview CC2420 can be configured to achieve the best performance for different a...

CC2420 SWRS041B Page 26 of 89 12 Evaluation Software Texas Instruments (TI) provides users of CC2420 with a software program, SmartRF ® Studio (Windows interface) which may be used for radio performance and functionality evaluation. SmartRF® Studio can be downloaded from TI’s web page: http://www.ti...

CC2420 SWRS041B Page 27 of 89 13 4-wire Serial Configuration and Data Interface CC2420 is configured via a simple 4-wire SPI-compatible interface (pins SI , SO , SCLK and CSn ) where CC2420 is the slave. This interface is also used to read and write buffered data (see page 39). All address and data ...

CC2420 SWRS041B Page 28 of 89 0 0 A5 A4 A3 A2 A0 A1 D W 15 D W 14 D W 13 D W 12 D W 11 D W 10 D W 9 D W 8 D W 7 D W 6 D W 5 D W 4 D W 3 D W 2 D W 1 D W 0 S7 S6 S5 S4 S3 S2 S0 S1 0 1 A5 A4 A3 A2 A0 A1 D R 15 D R 14 D R 13 D R 12 D R 11 D R 10 D R 9 D R 8 D R 7 D R 6 D R 5 D R 4 D R 3 D R 2 D R 1 D R ...

CC2420 SWRS041B Page 29 of 89 Bit # Name Description 7 - Reserved, ignore value 6 XOSC16M_STABLE Indicates whether the 16 MHz oscillator is running or not 0 : The 16 MHz crystal oscillator is not running 1 : The 16 MHz crystal oscillator is running 5 TX_UNDERFLOW Indicates whether an FIFO underflow ...

CC2420 SWRS041B Page 30 of 89 divided into three memory banks: TXFIFO (bank 0), RXFIFO (bank 1) and security (bank 2). The FIFO banks are 128 bytes each, while the security bank is 112 bytes. A6:0 is transmitted directly after the RAM/Register bit as shown in Figure 9. For RAM access, a second byte ...

CC2420 SWRS041B Page 31 of 89 Address Byte Ordering Name Description 0x16F – 0x16C - - Not used 0x16B – 0x16A MSB LSB SHORTADR 16-bit Short address, used for address recognition. 0x169 – 0x168 MSB LSB PANID 16-bit PAN identifier, used for address recognition. 0x167 – 0x160 MSB LSB IEEEADR 64-bit IEE...

CC2420 SWRS041B Page 32 of 89 CSn SI ADDR ADDR DATA 8MSB DATA 8LSB DATA ADDR+1 SO ADDR TXFIFO DATA ADDR DATA ADDR+2 Status Status - - Status Status Status Status Command Strobe Register Read TXFIFO Write Figure 11. Multiple SPI Access Example 14 Microcontroller Interface and Pin Description When use...

CC2420 SWRS041B Page 33 of 89 14.2 Receive mode In receive mode, the SFD pin goes active after the start of frame delimiter (SFD) field has been completely received. If address recognition is disabled or is successful, the SFD pin goes inactive again only after the last byte of the MPDU has been rec...

CC2420 SWRS041B Page 34 of 89 Preamble SFD Length Data received over RF SFD Pin FIFO Pin FIFOP Pin, if threshold higher than frame length FIFOP Pin, if threshold lower than frame length SF D de te cte d Le ng th b yte re ce ive d La st M PD U by te re ce ive d Preamble SFD Length Data received over ...

CC2420 SWRS041B Page 35 of 89 Preamble SFD Length Data transmitted over RF SFD Pin SF D tra ns m itte d La st M PD U by te tr an sm itte d or TX u nd er flo w MAC Protocol Data Unit (MPDU) S T X O N co m m an d str ob e 12 symbol periods Automatically generated preamble and SFD Data fetched from TXF...

CC2420 SWRS041B Page 36 of 89 Digital IF Channel Filtering ADC Digital Data Filtering Frequency Offset Compensation Symbol Correlators and Synchronisation RSSI Generator I / Q Analog IF signal Data Symbol Output RSSI Average Correlation Value (may be used for LQI) Figure 16. Demodulator Simplified B...

CC2420 SWRS041B Page 37 of 89 additional zero symbols in SYNCWORD make CC2420 compliant with [1]. In reception, CC2420 synchronises to received zero-symbols and searches for the SFD sequence defined by the SYNCWORD register. The least significant symbols in SYNCWORD set to 0xF will be ignored, while...

CC2420 SWRS041B Page 38 of 89 There is no hardware support for the data sequence number, this field must be inserted and verified by software. CC2420 includes hardware address recognition, as described in the Address Recognition section on page 41. Bits: 0-2 3 4 5 6 7-9 10-11 12-13 14-15 Frame Type ...

CC2420 SWRS041B Page 39 of 89 MPDU Length byte n MPDU 1 MPDU 2 MPDU n-2 RSSI (signed) CRC / Corr 7 6 5 4 3 2 1 0 Bit number CRC OK Correlation value (unsigned) Data in RXFIFO Figure 21. Data in RXFIFO when MDMCTRL0.AUTOCRC is set 17 RF Data Buffering CC2420 can be configured for different transmit a...

CC2420 SWRS041B Page 40 of 89 Multiple data frames may be in the RXFIFO simultaneously, as long as the total number of bytes does not exceed 128. See the RXFIFO overflow section on page 33 for details on how a RXFIFO overflow is detected and signalled. 17.3 Unbuffered, serial mode Unbuffered mode sh...

CC2420 SWRS041B Page 41 of 89 18 Address Recognition CC2420 includes hardware support for address recognition, as specified in [1]. Hardware address recognition may be enabled / disabled using the MDMCTRL0.ADR_DECODE control bit. Address recognition is based on the following requirements, listed fro...

CC2420 SWRS041B Page 42 of 89 AUTOACK may be used for non-beacon systems as long as the frame pending field (see Figure 19) is cleared. The acknowledge frame is then transmitted 12 symbol periods after the last symbol of the incoming frame. This is as specified by [1] for non-beacon networks. Frame ...

CC2420 SWRS041B Page 43 of 89 20 Radio control state machine CC2420 has a built-in state machine that is used to switch between different operational states (modes). The change of state is done either by using command strobes or by internal events such as SFD detected in receive mode. The radio cont...

CC2420 SWRS041B Page 44 of 89 Wait for the specified crystal oscillator start-up time, or poll the XOSC16M_STABLE status bit Power Down (PD) [0] SXOSCON S T X O N IDLE [1] Wait until voltage regulator has powered up Voltage Regulator Off VREG_EN set low VREG_EN set high Chip Reset(pin or register) A...

CC2420 SWRS041B Page 45 of 89 21 MAC Security Operations (Encryption and Authentication) CC2420 features hardware IEEE 802.15.4 MAC security operations. This includes counter mode (CTR) encryption / decryption, CBC-MAC authentication and CCM encryption + authentication. All security operations are b...

CC2420 SWRS041B Page 46 of 89 flag setting is stored in the most significant byte of the nonce. The flag byte used for encryption and authentication is then generated as shown in Figure 26. The frame counter part of the nonce must be incremented for each new packet by software. 7 6 CTR Flag bits 7:6...

CC2420 SWRS041B Page 47 of 89 RX in-line security operations are always performed on the first frame currently inside the RXFIFO, even if parts of this have already been read out over the SPI interface. This allows the receiver to first read the source address out to decide which key to use before d...

CC2420 SWRS041B Page 48 of 89 21.8 Timing Table 8 shows some examples of the time used by the security module for different operations. Mode l(a) l(m) l(MIC) Time [us] CCM 50 69 8 222 CTR - 15 - 99 CBC 17 98 12 99 Stand- alone - 16 - 14 Table 8. Security timing examples 22 Linear IF and AGC Settings...

CC2420 SWRS041B Page 49 of 89 -60 -40 -20 0 20 40 60 -100 -80 -60 -40 -20 0 RF Level [dBm] RSSI Re gis te r Va lue Figure 27. Typical RSSI value vs. input power 24 Link Quality Indication The link quality indication (LQI) measurement is a characterisation of the strength and/or quality of a received...

CC2420 SWRS041B Page 50 of 89 25 Clear Channel Assessment The clear channel assessment signal is based on the measured RSSI value and a programmable threshold. The clear channel assessment function is used to implement the CSMA-CA functionality specified in [1]. CCA is valid when the receiver has be...

CC2420 SWRS041B Page 51 of 89 27 VCO and PLL Self-Calibration 27.1 VCO The VCO is completely integrated and operates at 4800 – 4966 MHz. The VCO frequency is divided by 2 to generate frequencies in the desired band (2400-2483.5 MHz). 27.2 PLL self-calibration The VCO's characteristics will vary with...

CC2420 SWRS041B Page 52 of 89 In applications where the internal voltage regulator is not used, connect VREG_EN and VREG_IN to ground. VREG_OUT shall be left open. Note that the battery monitor will not work when the voltage regulator is not used. VREG_IN Internal bandgap voltage reference 1.25 V VR...

CC2420 SWRS041B Page 53 of 89 The battery monitor is controlled through the BATTMON control register. The battery monitor is enabled and disabled using the BATTMON.BATTMON_EN control bit. The voltage regulator must also be enabled when using the battery monitor. The battery monitor status bit is ava...

CC2420 SWRS041B Page 54 of 89 C381 C391 XTAL XOSC16_Q1 XOSC16_Q2 C381 C391 XTAL XTAL XOSC16_Q1 XOSC16_Q2 Figure 30. Crystal oscillator circuit Item C L = 16 pF C381 27 pF C391 27 pF Table 10. Crystal oscillator component values 32 Input / Output Matching The RF input / output is differential ( RF_N ...

CC2420 SWRS041B Page 55 of 89 A Unit dBm RF Att 30 dB 1AVG 1SA Ref Lvl 3 dBm Ref Lvl 3 dBm Center 2.45 GHz Span 2 MHz 200 kHz/ RBW 10 kHz VBW 10 kHz SWT 50 ms -90 -80 -70 -60 -50 -40 -30 -20 -10 0 -97 3 Date: 23.OCT.2003 21:38:33 Figure 31. Single carrier output 33.2 Modulated spectrum The CC2420 ha...

CC2420 SWRS041B Page 56 of 89 A Unit dBm RF Att 30 dB Ref Lvl 0 dBm Ref Lvl 0 dBm SWT 5 ms Center 2.45 GHz Span 10 MHz 1 MHz/ 1AVG 1SA RBW 100 kHz VBW 100 kHz -90 -80 -70 -60 -50 -40 -30 -20 -10 -100 0 Date: 23.OCT.2003 21:34:19 Figure 32. Modulated spectrum plot

CC2420 SWRS041B Page 57 of 89 34 System Considerations and Guidelines SRD regulations International regulations and national laws regulate the use of radio receivers and transmitters. SRDs (Short Range Devices) for license free operation are allowed to operate in the 2.4 GHz band worldwide. The most...

CC2420 SWRS041B Page 58 of 89 34.6 Low-cost systems As the CC2420 provides 250 kbps multi- channel performance without any external filters, a very low-cost system can be made. A differential antenna will eliminate the need for a balun, and the DC biasing can be achieved in the antenna topology. 34....

CC2420 SWRS041B Page 59 of 89 • The RXCTRL1.RXBPF_LOCUR control bit should be set to 1. The simplest way of making a PER measurement will be to use another CC2420 as the reference transmitter. However, this makes it difficult to measure the exact receiver performance. Using a signal generator, this ...

CC2420 SWRS041B Page 60 of 89 ( λ /4). They are very easy to design and can be implemented simply as a “piece of wire” or even integrated into the PCB. The length of the λ /4-monopole antenna is given by: L = 7125 / f where f is in MHz, giving the length in cm. An antenna for 2450 MHz should be 2.9 ...

CC2420 SWRS041B Page 61 of 89 37 Configuration Registers The configuration of CC2420 is done by programming the 16-bit configuration registers. Complete descriptions of the registers are given in the following tables. After chip reset (from the RESETn pin or programmable through the MAIN.RESETn conf...

CC2420 SWRS041B Page 62 of 89 Address Register Register type Description 0x0E SAES S AES Stand alone encryption strobe. SPI_SEC_MODE is not required to be 0, but the encryption module must be idle. If not, the strobe is ignored. 0x0F - - Not used 0x10 MAIN R/W Main Control Register 0x11 MDMCTRL0 R/W...

CC2420 SWRS041B Page 63 of 89 MAIN (0x10) - Main Control Register Bit Field Name Reset R/W Description 15 RESETn 1 R/W Active low reset of the entire circuit should be applied before doing anything else. Equivalent to using the RESETn reset pin. 14 ENC_RESETn 1 R/W Active low reset of the encryption...

CC2420 SWRS041B Page 64 of 89 MDMCTRL0 (0x11) - Modem Control Register 0 Bit Field Name Reset R/W Description 15:14 - 0 W0 Reserved, write as 0 13 RESERVED_FRAME_MODE 0 R/W Mode for accepting reserved IEE 802.15.4 frame types when address recognition is enabled ( MDMCTRL0.ADR_DECODE = 1 ). 0 : Reser...

CC2420 SWRS041B Page 65 of 89 MDMCTRL1 (0x12)– Modem Control Register 1 Bit Field Name Reset R/W Description 15:11 - 0 W0 Reserved, write as 0. 10:6 CORR_THR[4:0] 20 R/W Demodulator correlator threshold value, required before SFD search. Note that on early CC2420 versions the reset value was 0. 5 DE...

CC2420 SWRS041B Page 67 of 89 RXCTRL0 (0x16) – Receive control register 0 Bit Field Name Reset R/W Description 15:14 - 0 W0 Reserved, write as 0. 13:12 RXMIXBUF_CUR[1:0] 1 R/W RX mixer buffer bias current. 0: 690uA 1: 980uA (nominal) 2: 1.16mA 3: 1.44mA 11:10 HIGH_LNA_GAIN[1:0] 0 R/W Controls curren...

CC2420 SWRS041B Page 71 of 89 SECCTRL1 (0x1A) - Security Control Register Bit Field Name Reset R/W Description 15 - 0 W0 Reserved, write as 0 14:8 SEC_TXL 0 R/W Multi-purpose length byte for TX in-line security operations: CTR : Number of cleartext bytes between length byte and the first byte to be ...

CC2420 SWRS041B Page 81 of 89 38 Test Output Signals The two digital output pins CCA and SFD , can be set up to output test signals defined by IOCFG1.CCAMUX and IOCFG1.SFDMUX . This is summarized in Table 12 and Table 13 below. CCAMUX Signal output on CCA pin Description 0 CCA Normal operation 1 ADC...

CC2420 SWRS041B Page 82 of 89 SFDMUX Signal output on SFD pin Description 0 SFD Normal operation 1 ADC_I[0] ADC, I-branch, LSB used for random number generation 2 DEMOD_RESYNCH_EARLY High one 16 MHz clock cycle each time the demodulator resynchronises early 3 LOCK_STATUS Lock status, same as FSCTRL....

CC2420 SWRS041B Page 84 of 89 40 Recommended layout for package (QLP 48) Note: The figure is an illustration only and not to scale. There are nine 14 mil diameter via holes distributed symmetrically in the ground pad under the package. See also the CC2420 EM reference design. 40.1 Package thermal pr...

CC2420 SWRS041B Page 85 of 89 40.3 Plastic tube specification QLP 7x7mm antistatic tube. Tube Specification Package Tube Width Tube Height Tube Length Units per Tube QLP 48 8.5 ± 0.2 mm 2.2 +0.2/-0.1 mm 315 ± 1.25 mm 43 40.4 Carrier tape and reel specification Carrier tape and reel is in accordance ...

CC2420 SWRS041B Page 86 of 89 42 General Information 42.1 Document History Revision Date Description/Changes SWRS041b 2007-03-19 Slightly changed optimum load impedance on Page 9 and 19 to better describe the Application circuit. SWRS041a 2006-12-18 Updated ordering information. Updated address info...

CC2420 SWRS041B Page 87 of 89 Revision Date Description/Changes 1.2 2004-06-09 Output power range: 24 dB (was 40 dB). Deleted option for single ended external PA. Adjacent channel rejection corrected to 46 dB for + 5MHz (was 39 dB), 39 dB for –5 MHz (was 46 dB) 58 dB for +10 MHz (was 53 dB) and 55 d...

CC2420 SWRS041B Page 88 of 89 43 Address Information Texas Instruments Norway AS Gaustadalléen 21 N-0349 Oslo NORWAY Tel: +47 22 95 85 44 Fax: +47 22 95 85 46 Web site: http://www.ti.com/lpwrf 44 TI Worldwide Technical Support Internet TI Semiconductor Product Information Center Home Page: support.t...

CC2420 SWRS041B Page 89 of 89 Asia Phone International +886-2-23786800 Domestic Toll-Free Number Australia 1-800-999-084 China 800-820-8682 Hong Kong 800-96-5941 India +91-80-51381665 (Toll) Indonesia 001-803-8861-1006 Korea 080-551-2804 Malaysia 1-800-80-3973 New Zealand 0800-446-934 Philippines 1-...

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