DEVELOPMENT KIT (Info Click here) * * * * * * * * * DNT900 900 MHz Frequency Hopping Spread Spectrum Transceiver Point-to-Point and Point-to-Multipoint Network Topologies Transmitter Power Configurable from 1 mW to 1 W RF Data Rate Configurable from 38.4 to 500 kb/s Serial Port Rate up to 460.8 kb/s for Streaming Applications 128-Bit AES Encryption Separate Serial Port for Diagnostics Analog and Digital I/O for Sensor Applications FCC and Canadian IC Certified for Unlicensed Operation The DNT900 FHSS transceiver module is a low cost, high-power solution for point-topoint and point-to-multipoint wireless systems in the 900 MHz ISM band. The RF output power of the DNT900 can be set from 1 mW to 1 W, and the RF data rate can be set from 38.4 to 500 kb/s. The DNT900 receiver includes a low-noise preamplifier protected by two SAW filters, providing an excellent combination of receiver sensitivity and out-ofband interference rejection. The DNT900 module includes analog, digital and serial I/O, providing the flexibility and versatility to serve applications ranging from cable replacements to sensor networks. The DNT900 transceiver module is easy to integrate and provides robust wireless communications up to 40 miles in line-of-sight installations. Low Cost 900 MHz FHSS Transceiver Module with I/O DNT900 Absolute Maximum Ratings Rating All Input/Output Pins Value Units -0.5 to +3.3 Non-Operating Ambient Temperature Range -40 to +85 V o Shown with Shield Removed C DNT900 Electrical Characteristics Characteristic Sym Notes Operating Frequency Range Hop Dwell Time Minimum Typical Maximum Units 902.75 927.25 MHz 5 200 ms Number of RF Channels 50 Modulation FSK RF Data Transmission Rates 1 38.4, 115.2, 200 and 500 kb/s -108 dBm Receiver Sensitivity: 10-5 BER @ 38.4 kb/s -5 10 BER @ 200 kb/s -98 -5 10 BER @ 500 kb/s Transmitter RF Output Power Levels Optimum Antenna Impedance RF Connection Network Topologies Access Schemes www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. 1 dBm -94 dBm 1, 10, 100, 250, 500, 1000 at 38.4 to 200 kb/s 1, 10, 85 at 500 kb/s mW 50 W DNT900P - U.FL Coaxial Connector DNT900C - U.FL Connector or PCB Pad Point-to-Point, Point-to-Multipoint CSMA and TDMA Page 1 of 7 DNT900 - 06/11/09 DNT900 Electrical Characteristics Characteristic Sym Notes Minimum Typical Maximum Units Number of Network Nodes: TDMA Mode 16 CSMA Mode unlimited ADC Input Range 0 ADC Input Resolution 3.3 10 ADC Sample Rate bits 10 ms Signal Source Impedance for ADC Reading PWM (DAC) Output Range 0 PWM (DAC) Output Resolution 2 PWM Output Period Primary Serial Port Baud Rates V 10 KW 3.3 V 8 bits 20 s 1.2, 2.4, 4.8, 9.6, 19.2, 28.8, 38.4, 57.6, 76.8, 115.2, 230.4, 460.8 kb/s 38.4 kb/s Diagnostic Serial Port Baud Rate Digital I/O: Logic Low Input Level -0.5 0.8 V Logic High Input Level 2 3.3 V Logic Input Internal Pull-up Resistor 50 200 KW Logic Input Internal Pull-down Resistor 50 180 KW +3.3 +5.5 Vdc 10 mVP-P 1200 mA Power Supply Voltage Range VCC Power Supply Voltage Ripple Peak Transmit Mode Current, 1 W Output Average Operating Receive Current: Base 105 mA Remote, No Data Transmission 35 mA Remote, 9.6 kb/s Continuous Data Stream 40 mA Remote, 115.2 kb/s Continuous Data Stream 53 mA Sleep Current 3 50 DNT900C Mounting Reflow Soldering DNT900P Mounting Socket 225 A Operating Temperature Range -40 85 o Operating Relative Humidity Range, Non-condensing 10 90 % C Notes: 1. The DNT900 achieves regulatory certification under FHSS rules at air data rates of 38.4, 115.2 and 200 kb/s. At 500 kb/s, the DNT900 achieves regulatory certification under "digital modulation" or DTS rules. The DNT900 still employs frequency hopping at 500 kb/s to mitigate the effects of interference and multipath fading, but hops on fewer, more widely spaced frequencies than at lower data rates. Maximum RF power at 500 kb/s is 85 mW. 2. PWM is set with an 8-bit value. DAC resolution is limited to 7 bits by residual ripple at output of low-pass filter. 3. Maximum sleep current occurs at +85 oC. CAUTION: Electrostatic Sensitive Device. Observe precautions when handling. www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. Page 2 of 7 DNT900 - 06/11/09 D N T 9 0 0 B lo c k D ia g r a m P K T _ D E T 1 R S V D 2 A D C _ R E F R S S I 3 4 G P IO 0 5 G P IO 1 6 G P IO 2 7 G P IO 3 8 P W M 0 9 F ilte r P W M 1 1 0 F ilte r S L E E P 1 1 A D C 2 1 2 A D C 1 A D C 0 1 3 R S V D 1 5 D IA G _ T X 1 6 D IA G _ R X 1 7 /C F G 1 8 V C C 1 9 G N D 2 0 C L K S I S O M ic r o c o n tr o lle r C S n IN T P W R R F T r a n s c e iv e r P K T D E T 4 3 T /R T /R F ilte r 4 2 4 1 R F IO P R E 1 4 3 6 3 7 3 8 3 9 4 0 R S V D 3 5 /R E S E T R S V D 3 4 R S V D 3 3 R S V D 3 2 V M O D 3 1 R S V D 3 0 R A D IO _ R X D 2 9 /H O S T _ C T S 2 8 R A D IO _ T X D 2 7 R S V D 2 6 /H O S T _ R T S 2 5 R S V D 2 4 /D C D 2 3 R S V D 2 2 A C T 2 1 G P IO 5 R e g G N D 3 .6 V G P IO 4 R e g G N D 3 .3 V Figure 1 DNT900 Hardware The major components of the DNT900 include a 900 MHz FHSS transceiver and a low current 32-bit microcontroller. The DNT900 operates in the 902 to 928 MHz ISM band. There are a number of selectable hopping patterns including patterns compatible with frequency allocations in the US, Canada, South America, Israel, Australia and New Zealand. The DNT900 has six selectable RF output power levels: 1, 10, 100, 250 and 500 mW plus 1 W. Also, there are four selectable RF transmission rates: 38.4, 115.2, 200 and 500 kb/s. The DNT900 includes a low-noise preamplifier protected by two SAW filters, providing an excellent blend of receiver sensitivity and out-of-band interference rejection that is especially important in outdoor applications. The DNT900 provides a variety of hardware interfaces. There are two UART serial ports, one for data and a second for diagnostics. The data port supports standard baud rates from 1.2 to 460.8 kb/s and the diagnostic port is fixed at 38.4 kb/s. Also included are three 10-bit ADC inputs, two 8-bit PWM outputs, and six general-purpose digital I/O ports. Four of the digital I/O ports support an optional interrupt-from-sleep mode when configured as inputs. The www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. radio is available in two mounting configurations. The DNT900C is designed for solder reflow mounting. The DNT900P is designed for plug-in connector mounting. DNT900 Firmware The DNT900 firmware can operate using either TDMA or CSMA channel access modes. TDMA supports up to 16 remotes with rapid, deterministic channel latency. CSMA provides carrier-sense managed channel access for an unlimited number of low-traffic remotes. DNT900 firmware will operate "out of the box" using its point-to-point transparent serial mode, with point-to-multipoint supported by the firmware's protocol mode. DNT900 firmware provides the user with a rich set of configuration options including a choice of hopping patterns, hopping dwell times, RF data transmission rates, serial port data rates and RF power levels, plus configurable analog and digital I/O lines. Data integrity is protected by 24-bit error detection, with optional ACK and automatic transmission retries or redundant transmissions. 128-bit AES encryption provides a high level of data security for sensitive applications. Sensor networks can take advantage of timer or event-based data reporting and remote node sleep cycling for extended battery life. Page 3 of 7 DNT900 - 06/11/09 DNT900 I/O Descriptions Pin Name I/O Description 1 PKT_DET O Packet detect output. Signal switches logic high at the end of the start-of-packet symbol and switches logic low at the end of the end-of-packet symbol on both received and transmitted packets. PKT_DET provides a timing reference for external use in network timing evaluations, etc. 2 RSVD - Reserved pin. Leave unconnected. 3 ADC_REF I ADC supply and external full scale reference voltage input. Voltage range is 2.4 to 3.3 Vdc. Connect pad 34 to this input to reference the ADC full scale reading to the module's 3.3 V regulated supply. 4 RSVD - Reserved pin. Leave unconnected. 5 GPIO0 I/O Configurable digital I/O port 0. When configured as an input, an internal pull-up resistor can be selected and interrupt from sleep can be invoked. When configured as an output, the power-on state is configurable. The sleep mode direction and state are also configurable. 6 GPIO1 I/O Configurable digital I/O port 1. Same configuration options as GPIO0. 7 GPIO2 I/O Configurable digital I/O port 2. Same configuration options as GPIO0. 8 GPIO3 I/O Configurable digital I/O port 3. Same configuration options as GPIO0. 9 PWM0 O 8-bit pulse-width modulated output 0 with internal low-pass filter. Filter is first-order, with a159 Hz 3 dB bandwidth. 10 PWM1 O 8-bit pulse-width modulated output 1 with internal low-pass filter. Filter is first-order, with a 159 Hz 3 dB bandwidth. 11 SLEEP/DTR I Active high module sleep input (active low DTR). When switched low after sleep, the module executes a power on-reset. Usually connected to host DTR. Connect to ground if SLEEP/DTR function not used. 12 ADC2 I 10-bit ADC input 0. Full scale reading is referenced to the ADC_REF input. 13 ADC1 I 10-bit ADC input 1. Full scale reading is referenced to the ADC_REF input. 14 ADC0 I 10-bit ADC input 2. Full scale reading is referenced to the ADC_REF input. 15 RSVD - Reserved pad. Leave unconnected. 16 DIAG_TX O Diagnostic UART transmitter output. 17 DIAG_RX I Diagnostic UART receiver input. 18 /CFG I Protocol selection input. Leave unconnected when using software commands to select transparent/protocol mode (default is transparent mode). Logic low selects protocol mode, logic high selects transparent mode. 19 VCC I Power supply input, +3.3 to +5.5 Vdc. 20 GND - Power supply and signal ground. Connect to the host circuit board ground. 21 GND - Power supply and signal ground. Connect to the host circuit board ground. 22 GPIO4 I/O Configurable digital I/O port 4. When configured as an input, an internal pull-up resistor can be selected. When configured as an output, the power-on state is configurable. 23 GPIO5 I/O Configurable digital I/O port 5. Same configuration options as GPIO4. 24 GND - Logic ground. 25 ACT O Data activity output, logic high when data is being transmitted or received. 26 /DCD O Default functionality is data carrier detect output, logic low on a remote when the module is locked to FHSS hopping pattern and logic low on a base station when at least one remote is connected to it. The sleep mode state of this pin and /HOST_CTS is jointly configurable. 27 RSVD - Reserved pin. Leave unconnected. 28 RSVD - Reserved pin. Leave unconnected. 29 RSVD - Reserved pin. Leave unconnected. www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. Page 4 of 7 DNT900 - 06/11/09 Pin Name I/O Description 30 /HOST_RTS I UART flow control input. The host sets this line low to allow data to flow from the DNT900 on the RADIO_TXD pin. When the host sets this line high, the DNT900 will stop sending data to the host. 31 RADIO_TXD O UART transmitter output. The DNT900 sends serial data to the host on this pin. The sleep mode state of this pin is configurable. 32 RADIO_RXD I UART receiver input. The DNT900 receives serial data from the host on this pin. 33 /HOST_CTS O UART flow control output. The DNT900 sets this line low to indicate it is ready to accept data from the host on the RADIO_RXD input. When the DNT900 sets this line high, the host must stop sending data. The sleep mode state of this pin and /DCD is jointly configurable. 34 VMOD O Module's +3.3 V regulated supply. Connect to pad 3 to support 3.3 V full scale and/or ratiometric ADC readings, etc. Current drain on this output should be no greater than 5 mA. 35 RSVD - Reserved pin. Leave unconnected. 36 RSVD - Reserved pin. Leave unconnected. 37 RSVD - Reserved pin. Leave unconnected. 38 RSVD - Reserved pin. Leave unconnected. 39 /RESET I Active low module hardware reset. 40 RSVD - Reserved pin. Leave unconnected. 41 GND - RF ground for the DNT900C only. Connect to the host circuit board ground plane. 42 RFIO I/O 43 GND - Alternate RF port for the DNT900C only. The antenna can be connected to this port with a 50 ohm stripline or coaxial cable. Leave unconnected when using the U.FL connector. RF ground for the DNT900C only. Connect to the host circuit board ground plane. D N T 9 0 0 C O u tlin e a n d M o u n tin g D im e n s io n s 2 .0 1 0 0 .0 4 0 0 .0 4 0 0 .1 0 0 1 1 .2 6 0 0 .5 9 5 4 0 0 .1 8 0 D im e n s io n s in in c h e s Figure 2 www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. Page 5 of 7 DNT900 - 06/11/09 C ir c u it B o a r d S tr ip lin e T r a c e D e ta il Trace Separation from 50 ohm Microstrip Length of Trace Run Parallel to Microstrip 100 mil 125 mil 150 mil 200 mil 200 mil 290 mil 250 mil 450 mil 300 mil 650 mil C o p p e r S tr ip lin e T ra c e C o p p e r G ro u n d P la n e F R -4 P C B M a te r ia l F o r 5 0 o h m im p e d a n c e W = 1 .7 5 * H Figure 3 Figure 4 DNT900C RFIO Stripline The DNT900C has a U.FL coaxial connector mounted near pad 42 for antenna connection (see Antenna Connector discussion below). It is also possible to connect an antenna using a stripline from pad 42. It is important that this connection be implemented as a 50 ohm stripline. Referring to Figure 3, the width of this stripline depends on the thickness of the circuit board between the stripline and the groundplane. For FR-4 type circuit board materials (dielectric constant of 4.7), the width of the stripline is equal to 1.75 times the thickness of the circuit board. Note D N T 9 0 0 P O u tlin e a n d M o u n tin g D im e n s io n s 2 .0 5 0 0 .0 5 0 0 .0 4 0 0 .1 0 0 1 1 .3 6 0 4 0 0 .2 8 5 0 .3 3 3 D im e n s io n s in in c h e s Figure 5 www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. Page 6 of 7 DNT900 - 06/11/09 that other circuit board traces should be spaced away from the stripline to prevent signal coupling, as shown in Figure 4. The stripline trace should be kept short to minimize its insertion loss. DNT900 Antenna Connector A U.FL miniature coaxial connector is provided on both DNT900 configurations for connection to the RFIO port. A short U.FL coaxial cable can be used to connect the RFIO port directly to an antenna. In this case the antenna should be mounted firmly to avoid stressing the U.FL coaxial cable due to antenna mounting flexure. Alternately, a U.FL coaxial jumper cable can be used to connect the DNT900 module to a U.FL connector on the host circuit board. The connection between the host circuit board U.FL connector and the antenna or antenna connector on the host circuit board should be implemented as a 50 ohm stripline. Referring to Figure 3, the width of this stripline depends on the thickness of the circuit board between the stripline and the groundplane. For FR-4 type circuit board materials (dielectric constant of 4.7), the width of the stripline is equal to 1.75 times the thickness of the circuit board. Note that other circuit board traces should be spaced away from the stripline to prevent signal coupling, as shown in Figure 4. The stripline trace should be kept short to minimize its insertion loss. D N T 9 0 0 P In te r fa c e C o n n e c to r P C B L a y o u t D e ta il 0 .1 (2 .5 ) 0 .1 (2 .5 ) 2 .0 (5 0 .8 ) M in im u m p la te d P C B h o le d ia m e te r 0 .0 3 ( 0 .7 5 ) 1 .9 (4 8 .3 ) 1 .2 6 C o n n e c to r s a r e F C I E le c tr o n ic s 7 5 9 1 5 - 4 2 0 L F o r e q u iv a le n t D im e n s io n s in in c h e s a n d ( m m ) Figure 6 Note: Specifications subject to change without notice. Part # M-0900-0000, Rev B www.RFM.com E-mail: info@rfm.com (c)2008-2009 by RF Monolithics, Inc. Page 7 of 7 DNT900 - 06/11/09